A new study from <a href="https://www.osu.edu/">Ohio State University</a> reveals what is going on inside of your <a href="https://www.earth.com/news/gut-brain-interactions-have-an-influence-on-diseases/">brain</a> when you get lost in a fictional fantasy. The experts discovered that the more immersed we become in the lives of our favorite characters of fiction, the more our brain activity reflects how much we identify with them.
&#8220;When they think about a favorite fictional character, it appears similar in one part of the brain as when they are thinking about themselves,&#8221; said study lead author Timothy Broom.
The research was focused on self-described fans of the HBO series &#8220;Game of Thrones.&#8221; The individuals were instructed to think about themselves, nine of their friends, and nine characters from the drama series. The participants also reported on which character they felt closest to and liked the most.
According to Broom, Game of Thrones was ideal for this study because it attracted a devoted fan base and the large cast presented a variety of characters that people could become attached to.
One of the key findings involved participants who scored highest on &#8220;trait identification.&#8221; These individuals agreed most strongly with statements like &#8220;I really get involved in the feelings of the characters in a novel.&#8221;
&#8220;People who are high in trait identification not only get absorbed into a story, they also are really absorbed into a particular character,&#8221; said Broom. &#8220;They report matching the thoughts of the character, they are thinking what the character is thinking, they are feeling what the character is feeling. They are inhabiting the role of that character.&#8221;
The researchers used an fMRI machine to measure activity in various parts of the brain through small changes in blood flow. As the participants&#8217; brains were scanned, they were evaluating themselves, their friends, and Game of Thrones characters. 
A part of the brain called the ventral medial prefrontal cortex (vMPFC) is known to show increased activity when people think about themselves and, to a lesser extent, when they think about close friends.
While in the fMRI, the individuals were shown a series of names &#8211; including themselves, friends, or characters &#8211; along with a trait, such as lonely, sad, trustworthy, or smart. The participants simply said &#8220;yes&#8221; or &#8220;no&#8221; to imply whether the trait fit the person.
As expected, the vMPFC was most active when people were evaluating themselves, less active when they evaluated friends, and least active when they evaluated characters from Game of Thrones.
However, among those who were high in trait identification, the vMPFC was more active when they thought about the fictional characters than it was for participants who identified less with the characters. This region of the brain was particularly active when the individuals evaluated the character they identified with the most.
Study co-author Dylan Wanger said the findings help explain how fiction can have such a big impact on some people.
&#8220;For some people, fiction is a chance to take on new identities, to see worlds though others&#8217; eyes and return from those experiences changed,&#8221; said Wagner.
&#8220;What previous studies have found is that when people experience stories as if they were one of the characters, a connection is made with that character, and the character becomes intwined with the self. In our study, we see evidence of that in their brains.&#8221;
The study is published in the journal <a href="https://academic.oup.com/scan">Social Cognitive and Affective Neuroscience</a>.
&#8211;&#8212;
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

What happens in your brain while you're lost in fiction

Cell biology is a world of constant motion and hidden structures. Much of what we know about cells comes from decades of research using microscopes, stains, and models. Yet, even in this well-charted territory, surprises still emerge - enter the "hemifusome."



This previously unknown organelle may help explain how cells sort, recycle, and discard their internal cargo. This function is vital to life and is often disrupted in instances of genetic disease.



The discovery of this organelle, which was made by scientists at the <a href="https://www.virginia.edu" target="_blank" rel="noreferrer noopener">University of Virginia</a> and the National Institutes of Health (<a href="https://www.nih.gov" target="_blank" rel="noreferrer noopener">NIH</a>), offers a new lens through which to study the inner workings of the cell. 



It also presents a possible turning point for understanding diseases where cellular housekeeping breaks down. Using cutting-edge imaging tools, researchers have caught this <a href="https://www.earth.com/news/cambrian-explosion-fossils-push-back-the-rise-of-complex-life/">organelle</a> in action and outlined its potential impact on health and medicine.



<h2 class="wp-block-heading" id="h-introducing-the-hemifusome">Introducing the hemifusome</h2>



The hemifusome is not a static component but a temporary structure that appears and disappears depending on the cell’s needs. 



It consists of two vesicles joined together by a partial membrane connection called a hemifusion diaphragm.



In this configuration, the vesicles do not fully merge but maintain a shared boundary that allows them to interact without blending entirely.



"This is like discovering a new recycling center inside the cell," said researcher Seham Ebrahim, Ph.D., of UVA's Department of Molecular Physiology and Biological Physics. 



"We think the hemifusome helps manage how <a href="https://www.earth.com/news/third-state-of-existence-beyond-life-and-death-confirmed-by-scientists/">cells</a> package and process material, and when this goes wrong, it may contribute to diseases that affect many systems in the body."



These hemifused vesicles appear in two configurations. In the direct form, a smaller vesicle is attached to the outer side of a larger one, whereas in the flipped version, the smaller vesicle is embedded on the inner, or luminal, side. 



In both cases, a dense particle called a proteolipid nanodroplet anchors the structure at the junction, possibly guiding its formation and stability.



<h2 class="wp-block-heading" id="h-how-the-hemifusome-appears">How the hemifusome appears</h2>



To study hemifusomes, researchers turned to cryo-electron tomography (cryo-ET). This imaging method freezes cells rapidly, preserving them close to their natural state. 



Unlike traditional <a href="https://www.earth.com/news/watching-electrons-move-1-quintillionth-of-second-attoseconds-attomicroscopy/">electron microscopy</a>, which can distort or destroy delicate structures, cryo-ET allows scientists to see cellular architecture as it truly exists.



By scanning the outer edges of four mammalian cell types, COS-7, HeLa, RAT-1, and NIH/3T3, the team identified hundreds of hemifusomes. These organelles made up nearly 10 percent of all membrane-bound vesicles in those regions. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/07/hemifused-vesicles_cryo-electron-tomography_Nature-Communications_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/07/hemifused-vesicles_cryo-electron-tomography_Nature-Communications_1s.webp" alt="Cryo-electron tomography observation of hemifused vesicles at the leading edge of cultured cells. Credit: Nature Communications (2025)" class="wp-image-1976051"/></a><figcaption class="wp-element-caption">Cryo-electron tomography observation of hemifused vesicles at the leading edge of cultured cells. Click image to enlarge. Credit: Nature Communications (2025)</figcaption></figure>



Their consistency across <a href="https://www.earth.com/news/why-millions-of-fungal-species-still-remain-unknown/">cell</a> types suggests they are not rare anomalies but common cellular components.



"You can think of vesicles like little delivery trucks inside the cell," said Ebrahim, of UVA's Center for Membrane and Cell Physiology. "The hemifusome is like a loading dock where they connect and transfer cargo. It's a step in the process we didn't know existed."



<h2 class="wp-block-heading" id="h-what-makes-the-hemifusome-unique">What makes the hemifusome unique</h2>



Hemifusomes stand out not just for their shape, but for what’s inside them. The larger vesicle usually contains granular material, similar to what is seen in <a href="https://www.earth.com/news/mitochondria-cells-batteries-leaking-causes-inflammation-diseases/">endosomes</a> and ribosome-associated vesicles.



But the smaller vesicle shows a smooth, translucent interior. This likely reflects a protein-free or dilute aqueous solution, setting it apart from other vesicles in the cell.



The hemifusion diaphragm itself is unusually large, about 160 nanometers in diameter, far bigger than the 10 nanometer diaphragms seen in standard vesicle fusion <a href="https://www.earth.com/news/gold-eating-fungus-discovery-could-revolutionize-the-search-for-metals-and-minerals-on-earth-asteroids-and-other-planets/">events</a>. These extended diaphragms appear stable, not fleeting, suggesting they may be designed to last. 



In some cases, the diaphragm grows large enough to engulf the entire smaller vesicle into the larger one’s bilayer, creating a lens-like shape known in simulations as dead-end hemifusion. Seeing this in actual cells challenges the idea that such formations are purely theoretical.



<h2 class="wp-block-heading" id="h-anchors-and-architects-of-the-organelle">Anchors and architects of the organelle</h2>



One consistent feature at the heart of hemifusomes is the dense proteolipid nanodroplet, or PND. About 42 nanometers in diameter, these droplets are lodged at the rim of the hemifusion site. 



Their content, lipids and proteins, suggests they may help build or stabilize the hemifused structure.



These PNDs have never been observed in such a role before. Some appear free in the cytoplasm, others are embedded in membranes. Researchers propose that PNDs may serve as scaffolds for assembling new vesicles. 



As the PND integrates into a membrane, it may kickstart the formation of the smaller vesicle seen in hemifusomes.



This process, described as <a href="https://www.sciencedirect.com/topics/neuroscience/vasculogenesis" target="_blank" rel="noreferrer noopener">de novo vesiculogenesis</a>, stands apart from classical vesicle fusion. The presence of a unique, translucent vesicle and the absence of known docking steps indicate the hemifusome may follow its own assembly path.



<h2 class="wp-block-heading" id="h-are-hemifusomes-related-to-endosomes">Are hemifusomes related to endosomes?</h2>



Given their location and size, hemifusomes resemble some endosomal structures. To investigate this further, the researchers traced the journey of gold nanoparticles, common markers used to map endocytic activity. 



The particles entered known endosomes and <a href="https://www.earth.com/news/tricking-cells-into-thinking-they-ate-less-food-can-slow-aging-process/">lysosomes</a> but never appeared inside hemifusomes. This absence suggests that hemifusomes do not belong to the classical endocytic pathway.



Instead, they may represent a separate system operating independently of the cargo sorting carried out by proteins like ESCRT. This distinction may have wide implications for how we understand vesicle traffic inside cells.



<h2 class="wp-block-heading" id="h-multivesicular-bodies-and-disease">Multivesicular bodies and disease</h2>



Some hemifusomes evolve into more complex structures. The study observed compound hemifusomes that contained multiple vesicles, all partially fused. 



These could be early versions of <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/multivesicular-body" target="_blank" rel="noreferrer noopener">multivesicular bodies</a> (MVBs), which cells use to break down and recycle internal material.



In the canonical model, ESCRT proteins form inward buds that eventually pinch off inside a larger vesicle. But in hemifusomes, vesicles grow inward through hemifusion and expand with the help of PNDs. 



This alternative route might explain how MVBs form in ways not covered by traditional theories.



One such condition affected by these pathways is Hermansky-Pudlak syndrome. It is a genetic disorder marked by defects in pigmentation, lung function, vision, and bleeding. <a href="https://www.earth.com/news/damaged-mitochondria-recycled/">Cellular recycling</a> issues are central to the disease.



Understanding the hemifusome may help explain these disruptions and lead to future treatments.



<h2 class="wp-block-heading" id="h-a-new-model-for-vesicle-formation">A new model for vesicle formation</h2>



The study proposes a full model where PNDs trigger the formation of translucent vesicles that partially fuse with larger ones, forming hemifusomes. 



These structures may then bud inward, transforming into flipped hemifusomes. Over time, they could scission off as free vesicles inside MVBs.



In contrast to the ESCRT system, which requires tight protein coordination, this mechanism relies on structural and biophysical cues. 



It also sidesteps the need for large lipid donations from other organelles, solving a long-standing puzzle in vesicle formation research.



"This is just the beginning," Ebrahim said. "Now that we know hemifusomes exist, we can start asking how they behave in healthy cells and what happens when things go wrong. That could lead us to new strategies for treating complex genetic diseases."



<h2 class="wp-block-heading" id="h-what-comes-next">What comes next</h2>



The implications of this discovery stretch far beyond cell biology. By offering a new pathway for how cells build and manage internal compartments, the hemifusome challenges decades of assumptions. 



It also invites new thinking about disease, especially conditions where cells fail to manage their waste.



Future research will focus on identifying what proteins guide hemifusome formation and how PNDs are created. 



Scientists also want to know if these structures exist in other parts of the cell, not just at the periphery. Advanced imaging tools and genetic models will be key to answering these questions.



In a field where many believed the major organelles were already mapped, the hemifusome serves as a reminder. The cell still holds secrets. And some of them could lead to cures.



The study is published in the journal <a href="https://www.nature.com/articles/s41467-025-59887-9" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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Scientists discover a new organelle inside human cells with huge potential impact on health

Cell biology is a world of constant motion and hidden...

A fresh set of numbers is changing what scientists thought happens when a city‑sized slab of ice dissolves into the sea. The target was <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2023GL104028">mega‑iceberg</a> A‑68A, a floating platform roughly twice the area of Delaware that drifted toward South Georgia in early 2021.



“We think this is the first time measurements have been made so close to an iceberg,” said <a href="https://www.bas.ac.uk/profile/nacas/" target="_blank" rel="noreferrer noopener">Natasha Lucas of the British Antarctic Survey</a>, lead author of the new study. 



For the first time, researchers steered robotic vehicles to within 14 mi of such a iceberg and kept them there long enough to watch meltwater, temperature, and life interact in real time.&nbsp;



<h2 class="wp-block-heading" id="h-tracking-the-a-68a-iceberg">Tracking the A-68A iceberg</h2>



A‑68A calved from the Larsen C Ice Shelf <a href="https://www.earth.com/news/iceberg-larsen-c-antarctica/">back in 2017</a>, then rode the currents of the <a href="https://www.asoc.org/learn/welcome-to-the-southern-ocean/" target="_blank" rel="noreferrer noopener">Southern Ocean</a> on a five‑year tour that ended near South Georgia. 



<a href="https://www.earth.com/news/small-satellites-are-monitoring-ocean-conditions-from-space/">Satellites</a> could trace its general route, but ships kept their distance because the iceberg’s smaller rifts and spins defied prediction.



That standoff ended when a six‑foot‑long glider slipped off the deck of the <a href="https://noc.ac.uk/facilities/ships/rrs-james-cook" target="_blank" rel="noreferrer noopener">research vessel RRS James Cook</a> and began diving and climbing through a 0.6‑mile‑deep column of water. 



Over 49 days it logged 265 vertical profiles, sending each packet of data to scientists piloting the craft from home offices locked down by COVID‑19 restrictions.



The adventure was not entirely smooth. One glider vanished in the melee of drifting growlers, and another spent 17 days wedged beneath the berg before currents spat it out, battery blinking but sensors intact. 



Still, the mission mapped a zone of ocean that had never been observed so closely or for so long.



<h2 class="wp-block-heading" id="h-sensors-beneath-a-68a">Sensors beneath A-68A</h2>



The glider recorded a frosty cap of freshwater spreading across the top 30 ft of the sea. Right below, the instruments found a band of cold winter water that had lost its usual punch, a sign that melt‑driven turbulence had chewed away the seasonal layer separating surface and depth.



As that barrier thinned, nutrient‑rich deep water began sliding upward, carrying iron and silica shaved from the iceberg’s base. 



The upheaval altered local stratification, flipping the normal stack of density and temperature that keeps layers neatly in place during the Antarctic summer.



Salinity told the same story. At barely two miles from A‑68A, the profiles showed tongue‑shaped intrusions of water warmer and saltier than their neighbors, hallmarks of <a href="https://www.earth.com/news/life-survived-when-earth-was-covered-in-ice-but-how/">meltwater</a> plumes that had raced up the iceberg’s base before fanning out sideways.



<h2 class="wp-block-heading" id="h-a-68a-fuels-ocean-life">A‑68A fuels ocean life</h2>



Plankton reacted almost immediately. Near the ice wall, the glider’s fluorometer logged low <a href="https://oceantracks.org/library/oceanographic-factors/chlorophyll" target="_blank" rel="noreferrer noopener">chlorophyll</a> and high backscatter, evidence that meltwater diluted existing blooms while also dumping silt that clouded the light.



Farther away, a spike in <a href="https://www.earth.com/news/shifting-ocean-color-is-pushing-marine-life-toward-the-poles/">chlorophyll</a> flared about 36 hours after the iceberg’s passage, matching lab‑measured growth rates for the local phytoplankton community.



The burst hints that the same plume which first thinned the bloom later primed the water with micronutrients, a one‑two punch that temporarily shuffled who eats whom in the surface ocean.



Because upwelling also lifts dissolved carbon and heat, even short‑lived events like this matter to krill, fur seals, and the economy of South Georgia’s fisheries.



<h2 class="wp-block-heading" id="h-carbon-questions-on-a-cold-frontier">Carbon questions on a cold frontier</h2>



The carbon sink south of 35° S absorbs roughly 40 percent of humanity’s <a href="https://www.earth.com/news/creating-forests-cant-realistically-cancel-out-fossil-fuel-emissions/">fossil‑fuel emissions</a>. How that service will fare as calving accelerates remains uncertain.



The new findings show giant bergs can raise near‑surface stratification yet also stir the mid‑depths, two adjustments that tug carbon uptake in opposite directions. 



Recent model work argues current estimates may already overshoot Southern Ocean uptake by up to 0.4 Pg C yr‑1. Field evidence like the A‑68A data set will help sort winners from losers in that accounting.



<h2 class="wp-block-heading" id="h-risk-reward-and-remote-control">Risk, reward, and remote control</h2>



Flying a glider next to a iceberg the size of Los Angeles is an exercise in calculated gamble. Lucas and colleagues guided their craft from desks more than 7,500 miles away, relying on patchy satellite snapshots to dodge smaller ice.



When the glider went missing under the berg, frustration turned to nervous excitement, then relief as it resurfaced with a <a href="https://www.earth.com/news/supergiant-gold-deposit-find-claims-to-be-the-worlds-largest-discovery-ever/">gold mine</a> of temperature and salinity profiles. 



That trove fixed the first real numbers on basal melt rate, pegging it at roughly 6.9 × 10^8 m³ per day, an estimate within a factor of two of satellite calculations derived from changes in the iceberg’s freeboard height.



<h2 class="wp-block-heading" id="h-icebergs-preview-ocean-changes">Icebergs preview ocean changes</h2>



A‑68A is gone now, splintered into shards tracked only by radar, but younger cousins are lining up. The trillion‑ton A‑23A grounded off South Georgia this <a href="https://earthobservatory.nasa.gov/images/154022/iceberg-grinds-to-a-stop-off-south-georgia-island" target="_blank" rel="noreferrer noopener">March</a>, parking just 43 miles from the shore.



Researchers expect more deep‑drafted icebergs to exit West Antarctica as warming currents nibble ice shelves. 



Each one represents a floating lab, a hazard to shipping, and an agent of surprise for ecosystems that evolved around predictable cycles of light and nutrients.



The new study proves those labs are accessible with today’s tools. It also shows that a single iceberg can redraw local physics and biology in days, a reminder that climate change sends ripple effects far beyond melting ice.



The study is published in <a href="https://www.nature.com/articles/s41561-025-01659-7" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>.



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Scientists measure marine environment near melting mega-iceberg for first time

A fresh set of numbers is changing what scientists thought...

Far beneath the Pacific, where the Philippine Sea Plate dives under Japan, researchers have finally caught a peculiar kind of earthquake in the act.



Instead of lurching violently, the shallow end of the Nankai Trough crept for weeks, shifting only millimeters at a time while instruments buried in the seabed recorded every move.



“It's like a ripple moving across the plate interface,” said Josh Edgington, who analyzed the data while completing his PhD at the <a href="https://ig.utexas.edu/">University of Texas Institute for Geophysics</a> (UTIG).



The event - technically a slow-slip earthquake - was first spotted in autumn 2015 and repeated in 2020. Each episode unzipped roughly 20 miles of the fault in slow motion, starting about 30 miles off Japan’s Kii Peninsula and migrating seaward toward the <a href="https://www.earth.com/news/deep-ocean-trenches-holding-water/">ocean trench</a>.



Onshore seismometers and GPS receivers were oblivious. Only a new network of borehole observatories, drilled hundreds of feet into the seabed, was sensitive enough to detect motion so subtle.



<h2 class="wp-block-heading" id="h-detecting-earthquakes-from-below">Detecting earthquakes from below</h2>



Those boreholes are part of Japan’s ambitious scientific-<a href="https://www.earth.com/news/drilling-hole-reveals-significant-presence-of-high-grade-gold-and-silver-navidad-deposit/">drilling</a> program, which set out to plug the blind spot in global earthquake monitoring.



Land-based arrays can pinpoint sudden jolts but cannot “listen” to the shallows of subduction zones - precisely the places where tsunami-spawning ruptures begin. Installed sensors measure fluid pressure, strain and tilt with exquisite precision, allowing scientists to see how strain accumulates and releases in real time.



For UTIG director Demian Saffer, who led the study, the advantage is obvious. Slow-slip signals, he said, give researchers a direct view of how the shallow plate boundary behaves between major quakes.



If this creeping zone regularly releases stress, it could limit the size of future <a href="https://www.earth.com/news/650-foot-mega-tsunami-sends-seismic-waves-around-world-dickson-fjord-swot-mission/">tsunamis</a>. If not, the locked portion of the fault farther down-dip might still be primed for a magnitude-8 or 9 shock, similar to 1946, when a great Nankai earthquake leveled towns and killed more than 1,300 people.



<h2 class="wp-block-heading" id="h-water-helps-faults-slip">Water helps faults slip</h2>



Both slow-slip events tracked by the borehole array unfolded in regions where pore-fluid pressures are unusually high.



That correlation supports a popular but difficult-to-prove theory: overpressured fluids lubricate faults, allowing sections to move quietly rather than break catastrophically.



In the Nankai data, the link is as clear as it has ever been, offering a new metric for judging the tsunami potential of similar faults worldwide.



<h2 class="wp-block-heading" id="h-tsunami-signs-from-afar">Tsunami signs from afar</h2>



While parts of Nankai appear to “creak and groan” in slow motion, the equivalent shallow segment off the Pacific Northwest known as <a href="https://www.earth.com/news/most-dangerous-part-of-this-west-coast-earthquake-fault-cascadia-subduction-zone/">Cascadia</a> may be silent. 



That worries scientists, because a silent, locked interface stores energy that can unleash one of Earth’s rare magnitude-9 megathrusts and the devastating tsunamis that follow.



“This is a place that we know has hosted magnitude 9 earthquakes and can spawn deadly tsunamis,” Saffer said.



“Are there creaks and groans that indicate the release of accumulated strain, or is fault near the trench deadly silent? Cascadia is a clear top-priority area for the kind of high-precision monitoring approach that we’ve demonstrated is so valuable at Nankai.”



Installing similar borehole observatories along Cascadia, Chile, and Indonesia - other corners of the Pacific “Ring of Fire” - could reveal whether those margins harbor their own stealthy slow quakes or remain locked tight to the trench. 



The answer would refine tsunami-hazard forecasts and perhaps buy coastal communities critical minutes of warning.



<h2 class="wp-block-heading" id="h-creeping-fault-limits-big-earthquakes">Creeping fault limits big earthquakes</h2>



Taken together, the 2015 and 2020 Nankai slow-slip episodes suggest the shallow <a href="https://www.earth.com/news/most-dangerous-part-of-this-west-coast-earthquake-fault-cascadia-subduction-zone/">fault</a> functions more like a tectonic shock absorber than a ticking bomb. By periodically releasing energy, it might reduce how much strain transfers to deeper, more dangerous segments.



Yet the scientists caution against complacency. The deeper Nankai interface and neighboring segments could still fail suddenly, as history shows.



For now, geophysicists are analyzing the rich new dataset to model how fluids, <a href="https://www.earth.com/news/solar-heat-and-earthquake-activity-is-there-a-connection/">temperature</a>, and rock composition govern the transition from silent creep to violent rupture.



Each slow-slip event is another frame in an expanding time-lapse of the earthquake cycle - one that could eventually reveal when the next big snap is likely to occur.



<h2 class="wp-block-heading" id="h-hearing-earthquakes-before-they-roar">Hearing earthquakes before they roar</h2>



Catch a fault in the middle of a slow-motion glide and you learn a simple truth: not every earthquake shouts. Some only whisper, rippling quietly through kilometres of rock.



By wiring the seabed for sound, scientists have begun to hear those whispers and, with them, the hidden conversations that decide when Earth decides to roar.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.ads9715">Science</a>.



Image Credit: Japan Meteorological Agency 



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Scientists detect a rare slow-motion earthquake along Japan’s tsunami fault

Far beneath the Pacific, where the Philippine Sea Plate dives...

Being cool can feel elusive and almost mythic - something we “know when we see it,” yet struggle to define.



A sweeping new investigation led by marketing scholars Todd Pezzuti of <a href="https://www.uai.cl/">Universidad Adolfo Ibáñez</a> and Caleb Warren of the <a href="https://www.arizona.edu/">University of Arizona</a> argues that the concept is far less mysterious than it seems.



Across twelve nations, nearly 6,000 participants independently picked out the same constellation of <a href="https://www.earth.com/news/personality-type-can-accurately-predict-your-relationship-status/">personality</a> traits when describing a cool person. 



The findings reveal not only what separates “cool” from “good” but also why cool people tend to become catalysts of social change.



<h2 class="wp-block-heading" id="h-mapping-cool-across-12-nations">Mapping cool across 12 nations</h2>



Between 2018 and 2022, the research team collected online responses from adults in the United States, Australia, Chile, mainland China, Hong Kong, Germany, India, Mexico, Nigeria, Spain, South Africa, South Korea, and Turkey.



Participants first confirmed that they understood the slang meaning of the word “cool,” then spent a few minutes imagining someone who embodied one of four labels: cool, uncool, good, or not good.



Afterward, volunteers evaluated that imagined person on a battery of personality dimensions drawn from psychology’s “Big Five” model and Schwartz’s theory of universal values.



Because all responses came from internet users in relatively urban settings, the sample leans toward technologically connected citizens. 



Still, it is one of the most culturally diverse datasets ever assembled to study reputational judgments. The result is a uniquely global snapshot of how people assign social prestige.



<h2 class="wp-block-heading" id="h-where-cool-and-good-part-ways"><a></a>Where cool and good part ways</h2>



When the investigators compared ratings, they found considerable overlap: both cool and good people scored high on <a href="https://www.earth.com/news/people-with-many-facial-expressions-seem-more-social-and-likeable/">likability</a>. Yet important divergences emerged.



In all the places they studied, people consistently perceived cool individuals as more extraverted, hedonistic, powerful, adventurous, open, and autonomous. 



Good people, by contrast, ranked as conforming, traditional, secure, warm, agreeable, universalistic, conscientious, and calm.



<h2 class="wp-block-heading" id="h-cool-people-aren-t-always-good">Cool people aren't always "good"</h2>



In Pezzuti’s view, the cool profile evokes a kind of charismatic boundary-pusher: energetic, novelty seeking, and unapologetically self-directed.



That explains why cool individuals can inspire fashion trends or launch creative movements - roles that sometimes require bending social rules rather than following them.



“To be seen as cool, someone usually needs to be somewhat likable or admirable, which makes them similar to good people," said Warren. "However, cool people often have other traits that aren’t necessarily considered ‘good’ in a moral sense, like being hedonistic and powerful.”



The cool persona therefore straddles acceptance and transgression: admired enough to influence peers, rebellious enough to feel fresh.



<h2 class="wp-block-heading" id="h-cool-traits-go-global">Cool traits go global</h2>



In the mid-20th century, “cool” circulated in small countercultures - from Black jazz clubs to Beatnik cafés. Over the decades, fashion labels, record companies and Hollywood studios harnessed the aura of cool, broadcasting certain looks and attitudes to a worldwide audience.



The new study suggests that process may have standardized the meaning of the term. Even participants who live 10,000 miles apart now recognize the same signature <a href="https://www.earth.com/news/personality-traits-linked-to-willingness-to-volunteer-or-donate/">traits</a>. As the authors note, the meaning of cool has crystallized on a similar set of traits and values around the world.



Pezzuti does not see commercialization as a death knell. “Coolness has definitely evolved over time, but I don’t think it has lost its edge. It’s just become more functional,” he said.



“The concept of coolness started in small, rebellious sub-cultures, including Black jazz musicians in the 1940s and the beatniks in the 1950s. As society moves faster and puts more value on creativity and change, cool people are more essential than ever.”



<h2 class="wp-block-heading" id="h-why-coolness-matters">Why coolness matters</h2>



Because cool people display power and autonomy while earning admiration, the researchers argue that coolness helps establish informal hierarchies. Instead of relying solely on wealth or institutional authority, communities also elevate figures who embody daring and originality.



These individuals, in turn, shape cultural norms by modeling alternative ways to dress, speak, or live. As Pezzuti puts it, “everyone wants to be cool, or at least avoid the stigma of being uncool, and society needs cool people because they challenge norms, inspire change, and advance culture.”



That dual role - both aspirational and disruptive - makes the cool persona uniquely influential. Marketers know this instinctively when they cast charismatic musicians in sneaker ads. Activists harness it when they infuse protest art with edgy style.



The study provides empirical backing for those intuitions: people from Lagos to Los Angeles consistently associate coolness with adventurous independence.



<h2 class="wp-block-heading" id="h-coolness-in-the-digital-age">Coolness in the digital age</h2>



The team notes their study excludes rural and offline groups, whose ideas of cool may differ significantly. They also restricted the study to cultures already familiar with the English slang term, potentially narrowing linguistic nuance.



Future projects could test whether the six-trait profile - extraverted, hedonistic, powerful, adventurous, open, and autonomous - holds in additional societies or emerges in other languages.



Researchers are likewise curious about how <a href="https://www.earth.com/news/social-media-pressure-is-straining-teen-friendships/">social media</a> platforms, which accelerate the spread of trends, might further synchronize or fragment global standards of cool. Does TikTok broaden identity through niche subcultures or reinforce the six-trait mold by favoring charismatic risk-takers?



For now, the evidence is striking: when people across five continents imagine someone undeniably cool, they picture remarkably similar qualities. 



Coolness, it turns out, may be one of the few cross-cultural constants - an unwritten code that transcends borders even as it keeps pushing boundaries.



The study is published in the <a href="https://psycnet.apa.org/doiLanding?doi=10.1037%2Fxge0001799">Journal of Experimental Psychology: General</a>.



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What makes people cool? Scientists tracked down the traits

Being cool can feel elusive and almost mythic - something...

For decades, oceanographers assumed the surface waters circling Antarctica were becoming progressively fresher - a shift that helped lock deep heat away and nurture expansive winter sea ice.



However, new observations show the opposite is now happening. An international team led by the <a href="https://www.southampton.ac.uk/">University of Southampton</a> reported a sudden rise in surface <a href="https://www.earth.com/news/salinity-is-rising-in-coastal-areas-and-hurting-farmlands/">salinity</a> south of 50° latitude. This shift coincided with the steepest drop in Antarctic sea-ice extent ever recorded.



The analysis combines European satellite data with readings from autonomous floats that profile the water column. The result reveals an unanticipated pivot in the Southern Ocean’s salt balance sometime after 2015.



<h2 class="wp-block-heading" id="h-excessive-salt-melts-sea-ice">Excessive salt melts sea ice</h2>



Cold, fresh surface water normally overlies warmer, saltier layers at depth, creating strong density “stratification” that traps heat below. When the surface grows saltier, that barrier weakens. Heat then mixes upward, <a href="https://www.earth.com/news/antarcticas-melting-ice-shelves-threaten-global-sea-levels/">melting sea ice</a> from beneath and preventing extensive winter growth.



“Saltier surface water allows deep ocean heat to rise more easily, melting sea ice from below," said lead author Alessandro Silvano, an oceanographer at the University of Southampton. "It's a dangerous feedback loop: less ice leads to more heat, which leads to even less ice.” 



Since 2015, the continent has shed sea ice equivalent to the area of Greenland. Researchers call it the largest environmental shift detected anywhere on Earth in recent decades.



<h2 class="wp-block-heading" id="h-sea-ice-hole-returns-after-decades">Sea ice hole returns after decades</h2>



One striking symptom is the re-opening of the <a href="https://www.earth.com/news/massive-hole-polynya-the-size-of-switzerland-appeared-in-the-antarctica-sea-ice/">Maud Rise polynya</a> - a yawning hole in the Weddell Sea ice cover. It spans nearly four times the size of Wales and last appeared in the late 1970s.



“The return of the Maud Rise polynya signals just how unusual the current conditions are,” Silvano said. “If this salty, low-ice state continues, it could permanently reshape the Southern Ocean - and with it, the planet.”



Reduced Antarctic ice darkens the ocean, absorbing more sunlight and already feeding back into the global climate system. This, as Silvano put it, will give rise to “stronger <a href="https://www.earth.com/news/rapid-antarctic-sea-ice-loss-is-causing-severe-storms-around-the-world/">storms</a>, warmer oceans, and shrinking habitats for Antarctic wildlife.”



<h2 class="wp-block-heading" id="h-old-predictions-fall-short">Old predictions fall short</h2>



Climate models had projected eventual Antarctic sea-ice loss under greenhouse forcing. However, many scientists believed that enhanced snowfall and increased melt from continental ice sheets would keep surface waters fresh for decades, delaying large declines. The new evidence challenges that assumption.



“While scientists expected that human-driven climate change would eventually lead to Antarctic sea ice decline, the timing and nature of this shift remained uncertain,” said co-author Aditya Narayanan, a physical oceanographer at the University of Southampton.



“Previous projections emphasized enhanced surface freshening and stronger ocean stratification, which could have supported sustained sea ice cover. Instead, a rapid reduction in sea ice - an important reflector of solar radiation - has occurred, potentially accelerating global warming.”



<h2 class="wp-block-heading" id="h-eyes-on-the-southern-ocean">Eyes on the Southern Ocean</h2>



Because this turnaround was detected only after <a href="https://www.earth.com/news/satellites-reveal-a-sudden-drop-in-global-freshwater-levels/">satellites</a> began tracking sea-surface salinity in detail, researchers worry that other rapid transitions might be missed without constant observation.



“The new findings suggest that our current understanding may be insufficient to accurately predict future changes,” said senior author Alberto Naveira Garabato, a professor of physical oceanography at the University of Southampton.



“It makes the need for continuous satellite and in-situ monitoring all the more pressing, so we can better understand the drivers of recent and future shifts in the ice-ocean system.”



<h2 class="wp-block-heading" id="h-sea-ice-loss-changes-the-planet">Sea ice loss changes the planet</h2>



Antarctic sea ice acts as a reflective shield, bouncing sunlight back to space and modulating heat exchange between ocean and atmosphere.



Its precipitous decline could amplify warming worldwide, disturb wind patterns, and alter the formation of the deep water masses that power global ocean circulation.



Saltier surface layers may also influence how much carbon the <a href="https://www.earth.com/news/carbon-storage-mystery-emerges-in-the-southern-ocean/">Southern Ocean</a> can absorb, potentially weakening one of Earth’s most important climate buffers.



<h2 class="wp-block-heading" id="h-heat-and-salt-reinforce-sea-ice-loss">Heat and salt reinforce sea ice loss</h2>



The study leaves open questions about what triggered the sudden salinity jump. Possibilities include shifts in wind patterns, changes in precipitation, or increased intrusion of warm Circumpolar Deep Water onto the continental shelf.



Whatever the cause, the new feedback between salt and sea ice could lock the region into a self-reinforcing cycle of warming and ice loss.



Scientists stress that only sustained measurements - combining satellites, autonomous floats, and ship-based surveys - will reveal whether the Southern Ocean snaps back to its former fresher state or continues toward an unfamiliar, saltier future.



For now, the message is clear: Antarctica’s floating fringe, once thought relatively resistant to near-term change, is undergoing a rapid transformation that matters far beyond the frozen continent.



The study is published in the journal <a href="https://www.pnas.org/doi/10.1073/pnas.2500440122">Proceedings of the National Academy of Sciences</a>.



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Antarctic sea ice collapse linked to a sudden surge in ocean salt

For decades, oceanographers assumed the surface waters circling Antarctica were...

When it comes to creativity, especially in brainstorming new and unusual uses for everyday objects, many people instinctively turn to Google. It's quick, easy, and feels helpful. But that habit might actually be holding group creativity back.



A recent study from researchers at <a href="https://www.cmu.edu/">Carnegie Mellon University</a> suggests that searching online before thinking for yourself may lead to more predictable - and less original - ideas.



<h2 class="wp-block-heading" id="h-creativity-at-a-cost">Creativity at a cost</h2>



The team asked participants to think of novel uses for two common items: umbrellas and shields. Some participants were allowed to use Google during the brainstorming process. Others were asked not to use the <a href="https://www.earth.com/news/internet-access-should-be-a-basic-human-right/">internet</a> at all.



On an individual level, both groups produced similarly creative ideas. But once grouped, a pattern emerged. Google users tended to echo the same ideas.



Study lead author Danny Oppenheimer is a professor in Carnegie Mellon University’s Department of Social and Decision Sciences.



“This appears to be due to the fact that Google users came up with the same common answers, often in the same order, as they relied on Google, while non-Google users came up with more distinct answers,” noted Professor Oppenheimer.



In other words, Google didn’t kill creativity entirely, but it did seem to homogenize it.



<h2 class="wp-block-heading" id="h-less-help-from-google-more-creativity">Less help from Google, more creativity</h2>



The objects chosen, umbrellas and shields, produced an unexpected split. <a href="https://www.earth.com/news/online-search-results-often-match-users-biases/">Online searches</a> generated plenty of alternative uses for umbrellas, but for shields - not so much.



That led to an interesting twist: participants had a harder time brainstorming ideas for umbrellas, even though Google offered more help. Shields, with fewer online suggestions, actually inspired more creative responses.



Why? The researchers believe it’s a case of "fixation effects." When people see a possible solution too early - especially a familiar one - they tend to stick to that path and struggle to think differently.



“For example, a person trying to brainstorm ‘things you might spread’ who sees other people, or Google, give answers like ‘butter’ or ‘jam’ is more likely to come up with other foods, such as cream cheese, and less likely to come up with non-food-based answers, like disease or rumors,” said Oppenheimer.



“This study is the first evidence of fixation effects being induced by internet search."



<h2 class="wp-block-heading" id="h-it-s-not-about-banning-the-internet">It's not about banning the internet</h2>



So, is the internet ruining our creativity? Not quite. "The internet isn’t making us dumb, but we may be using it in ways that aren’t helpful,” said Oppenheimer.



Instead of avoiding <a href="https://www.earth.com/news/how-does-digital-technology-influence-our-sense-of-self/">technology</a> altogether, the researchers suggest we rethink how we use it. Taking time to think offline before jumping into a search engine might help avoid falling into the fixation trap.



Sttudy co-author Mark Patterson is an assistant teaching professor in Carnegie Mellon University’s Department of Social and Decision Sciences.



“Many of us are sort of rethinking what our relationships with technology are like,” said Patterson.



“It feels like every week there’s some sort of mind-blowing, new advance, and I think one interpretation of our paper is a reminder about the important advantages that we have just as regular people trying to solve problems.”



<h2 class="wp-block-heading" id="h-holding-on-to-our-individuality">Holding on to our individuality </h2>



Patterson emphasized the value of original thought - even if it feels a little old-school.



“Even though it sounds like the kind of messaging you might get from your preschool teacher. Like, ‘You’re you, and you’re different, and you’re unique.’ That messaging actually does matter,” said Patterson. 



“We want to hold on to our <a href="https://www.earth.com/news/are-we-losing-our-uniqueness-people-have-less-desire-to-stand-out/">individuality</a> and our regular, un-tech-aided <a href="https://www.earth.com/news/how-humanity-can-work-together-to-solve-global-challenges/">humanity</a>, because it’s the thing that’s going to make us solve problems slightly differently than other people, and that can really be valuable.”



<h2 class="wp-block-heading" id="h-smarter-prompts-smarter-thinking">Smarter prompts, smarter thinking</h2>



The team also points to the importance of how we use technology - not just whether we use it.



“Our hope is that by studying how human thought interacts with technology use, we can figure out ways to glean the best of the internet while minimizing the negative consequences,” Oppenheimer said.



This might mean using better prompt strategies or doing a round of solo brainstorming before opening a browser. The goal isn’t to stop using online tools. It’s to use them smarter.



<h2 class="wp-block-heading" id="h-google-doesn-t-always-harm-creativity">Google doesn't always harm creativity </h2>



For most daily searches - quick facts, simple tasks - fixation isn’t a big problem. But for larger, more complex problems that require group input and diverse thinking, it could be.



“For some of these bigger, tough, societal-level challenges that we’re facing, I think taking advantage of real diversity and a wide range of solutions requires groups to come up with a lot of different solution strategies,” said Patterson.



In other words, creativity still starts with the human mind. The internet can help - but only if we don’t let it do all the thinking for us.



The full study was published in the journal <a href="https://link.springer.com/article/10.3758/s13421-025-01732-x">Memory &amp; Cognition</a>.



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How Google searches can limit your creativity

When it comes to creativity, especially in brainstorming new and...

Warsaw isn’t short on parks or tree-lined boulevards, but a trio of Polish universities wondered whether smaller, resident-run gardens could add something crucial to the capital’s climate resilience.



To find out, researchers from <a href="https://english.swps.pl/">SWPS University</a>, <a href="https://eng.pw.edu.pl/">Warsaw University of Technology</a>, and the <a href="https://www.sggw.edu.pl/en/">Warsaw University of Life Sciences</a> mapped every vacant meadow, former orchard, and post-industrial lot within easy walking distance of apartment blocks.



They came up with a staggering 1,864 hectares (4,600 acres) - more than enough space, they say, for a citywide network of community gardens that soak up stormwater, cool overheated streets, and capture <a href="https://www.earth.com/news/planting-diverse-crops-traps-carbon-and-boosts-soil-health/">carbon</a>.



The investigation combined that spatial analysis with more than 250 in-depth interviews. The goal was to see who is already gardening, what motivates them, and how much social capital - trust, shared norms, cooperative spirit - might be harvested alongside tomatoes and herbs.



<h2 class="wp-block-heading" id="h-who-uses-the-urban-gardens">Who uses the urban gardens</h2>



It turns out the movement is surprisingly broad. Urban gardening brings together all social groups, the team reports, from school children planting <a href="https://www.earth.com/news/pollinators-are-disappearing-and-its-bad-news-for-plants/">pollinator</a> patches to cultural institutions converting courtyards into micro-farms.



Still, two cohorts dominate the regular volunteer lists: retirees - often women with higher education - and young middle class families. 



Most gardens revolve around a core group of 10 to 15 steady hands, supplemented by casual helpers and passers-by who stop to chat, water, or simply lounge among the raised beds.



<h2 class="wp-block-heading" id="h-motivation-of-urban-gardeners">Motivation of urban gardeners </h2>



Why do they show up week after week? According to study co-author Piotr Majewski of SWPS University, the motivations of urban gardeners vary. 



"The most important ones are: reconnection to nature, positive contribution to the environment, social relations, and mutual learning between gardeners," said Majewski.



Food, interestingly, is not the primary driver. Leaders said harvests help, but real value comes from biodiversity, composting, and public workshops on sustainable living.



<h2 class="wp-block-heading" id="h-tiny-plots-big-impact">Tiny plots, big impact</h2>



Those activities tally with an expanding body of international research linking <a href="https://www.earth.com/news/reducing-carbon-footprint-urban-farms-and-agriculture/">urban agriculture</a> to climate adaptation. 



Even pocket-size plots act as carbon sinks, trap particulate pollution, and soften the urban heat island. Raised beds can be engineered to hold back flash-flood water, while compost heaps divert organic waste from <a href="https://www.earth.com/news/landfills-emit-exorbitant-amount-methane-into-atmosphere/">landfills</a>.



For Warsaw, the numbers are compelling. Nearly all of the identified 1,864 hectares (4,600 acres) lie within a quarter mile of housing, meaning a potential garden is no farther than a ten-minute stroll for most residents - and often half that.



Such proximity, the experts argue, makes it easier to harness gardens as a distributed green-infrastructure network in a warming metropolis of nearly two million people.



Yet the real strength may be social. Garden groups knit neighbors together, boosting the informal networks that cities rely on during <a href="https://www.earth.com/news/climate-change-has-made-heatwaves-more-deadly/">heatwaves</a>, floods, or other climate-related shocks.



Many interviewees said they joined to cultivate community first, vegetables second. Regular workdays double as impromptu skill‐shares: retirees pass on horticultural know-how, children learn ecological stewardship, and newcomers forge local friendships.



<h2 class="wp-block-heading" id="h-urban-gardens-in-city-plans">Urban gardens in city plans</h2>



Majewski and his colleagues believe Warsaw’s planners should take that social-ecological synergy seriously.



“The system of community gardens should also be considered as a tool to support <a href="https://www.earth.com/news/the-power-of-imagination-in-climate-change-adaptation/">climate change adaptation</a> solutions in urban policies in spatial planning - provided that they are considered an important link in the urban green infrastructure system,” he explained.



To get there, the researchers lay out a handful of recommendations. First, city hall could weave gardens into official zoning strategies rather than treating them as informal afterthoughts. 



That might mean leasing public land at peppercorn rents, streamlining permits, or integrating gardens into new housing estates from the design phase.



Second, municipal agencies could supply starter kits - soil, timber, rain barrels - while leaving day-to-day management to residents. Third, wider publicity would help spread the idea beyond the usual eco-activist circles.



<h2 class="wp-block-heading" id="h-scaling-gardens-citywide">Scaling gardens citywide</h2>



The study also flags areas for further research. At what point does a collection of isolated plots start delivering measurable cooling or flood mitigation benefits? 



How can Warsaw ensure that garden networks thrive in all districts, not just affluent ones with vocal community groups? And what responsibilities will fall on municipal departments when gardens become part of critical infrastructure rather than hobby spaces?



Those unknowns aside, the evidence is clear: Warsaw already hosts a vibrant cohort of “hero activists” who coax life from overlooked corners.



With modest institutional backing, their trowels and compost bins could double as climate-adaptation tools - cooling concrete and absorbing rainfall. 



Perhaps most importantly, they help draw neighbors together in a city that will need every ounce of solidarity as temperatures rise.



The study is published in the journal <a href="https://sciendo.com/article/10.2478/mgrsd-2025-0005">Miscellanea Geographic</a>.



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Urban gardens help cities fight climate change

Warsaw isn’t short on parks or tree-lined boulevards, but a...

New high‑pressure experiments show that the chemical recipe of Earth's deep mantle has barely budged since our planet formed 4.5 billion years ago. 



The finding, drawn from crushed rock samples held at pressures rivaling those 1,800 miles down, reshapes ideas about how oxygen and metals move through our planet’s interior.



The research centers on bridgmanite, the most common mineral on Earth yet one that never reaches the surface. 



After being squeezed until it glowed at 4,000 °F, the mineral kept almost the same ratio of ferric iron to total iron that scientists infer for early Earth, hinting at an enduring redox balance.



Lead author <a href="https://www.researchgate.net/profile/Fei-Wang-91" target="_blank" rel="noreferrer noopener">Fei Wang</a>, <a href="https://www.bgi.uni-bayreuth.de/?&amp;lng=en" target="_blank" rel="noreferrer noopener">Bavarian Research Institute</a> of Experimental Geochemistry &amp; Geophysics, and colleagues combined the lab data with thermodynamic models to track iron chemistry through the lower mantle.



<h2 class="wp-block-heading" id="h-why-earth-s-mantle-matters">Why Earth's mantle matters</h2>



Geologists care about the <a href="https://www.nature.com/articles/s41586-025-08701-z" target="_blank" rel="noreferrer noopener">lower mantle</a> because it locks in the planet’s earliest history and influences how volcanoes feed the surface. 



If its chemistry drifts over time, gases like carbon dioxide and water entering the atmosphere would shift too, altering climate and habitability.



Early models suggested that violent mixing during a global magma ocean phase might have reset the interior’s redox state. 



Yet samples of ancient <a href="https://conf.goldschmidt.info/goldschmidt/2021/meetingapp.cgi" target="_blank" rel="noreferrer noopener">diamonds</a> indicate the volatile mix inside Earth has matched today’s values since at least 2.7 billion years ago. Those diamonds act as time capsules, trapping mantle gases long before complex life emerged.



<h2 class="wp-block-heading" id="h-bridgmanite-under-crushing-pressure">Bridgmanite under crushing pressure</h2>



In the new study, the team packed powdered silicates with tiny metal sensors, then drove them to 730,000 pounds per square inch inside a multi‑anvil press. 



Temperature was held near 2,300 K so the crystals mirrored lower‑mantle conditions.



Despite equilibrium with <a href="https://www.earth.com/news/iron-was-lifes-first-essential-metal-and-shaped-early-evolution/">metallic iron</a>, bridgmanite still carried roughly 17 percent of its <a href="https://www.earth.com/news/geologists-found-the-worlds-largest-iron-ore-deposit/">iron</a> in the oxidized state, a figure almost identical across pressures from 400 to 1,000 miles depth. 



Similar laser‑heated diamond‑anvil experiments last year reached the same conclusion, showing ferric‑iron ratios unchanged by pressure across the mid‑mantle.



The key variable turned out to be temperature: hotter crystals shed ferric iron, while cooler ones gain it. 



That trend explains why Earth's current lower mantle may sit near the threshold where metallic iron precipitates, matching seismic hints of scattered iron blobs.



<h2 class="wp-block-heading" id="h-earth-s-mantle-in-the-early-days">Earth's mantle in the early days</h2>



Thermodynamic modeling stitched the lab data into a planet‑wide picture, simulating how the Fe³⁺/ΣFe ratio evolved as the magma ocean cooled. 



The results imply that only 0.2 weight percent of metallic iron separated into the core while the rest of the solid mantle held steady.



Such a small escape fits with earlier calculations showing that <a href="https://www.earth.com/news/earths-largest-iron-ore-deposits-reveal-a-1-3-billion-year-old-secret/">iron</a> droplets wet grain boundaries and percolate downward quickly at near‑solidus temperatures. 



Once the mantle fully crystallized, further oxidation stalled because the dominant substitution of Fe³⁺ and Al³⁺ in bridgmanite is remarkably pressure‑insensitive.



This built‑in stability means later plate recycling and plume activity simply stir existing chemistry rather than overhaul it. 



As a result, the upper mantle’s oxygen level rose to present values through slow mixing instead of fresh inputs.



<h2 class="wp-block-heading" id="h-stability-over-time">Stability over time</h2>



Observations outside the lab echo the model. Seismic <a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022JB025689" target="_blank" rel="noreferrer noopener">studies</a> find that the bulk sound speed of the mid‑mantle matches compositions with constant iron valence, leaving little room for dramatic chemical layering.



“These processes played a major role in the Earth being surrounded by an oxygen‑rich atmosphere,” said <a href="https://www.profilfelder.uni-bayreuth.de/en/advanced-fields/4_High_pressure-and-high--temperature-research/contributors/mccammon_catherine/index.php" target="_blank" rel="noreferrer noopener">Dr. Catherine McCammon</a> of the University of Bayreuth. 



Volatile ratios in volcanic gases also line up with Archean samples, reinforcing the idea of a long‑lived interior equilibrium. 



Diamond data add another hint: helium, neon, and argon proportions trapped in 2.7‑billion‑year‑old stones mirror those in modern basalts. 



“This was a surprising result. It means the volatile‑rich environment we see around us today is not a recent development,” noted <a href="https://crpg.univ-lorraine.fr/membres/michael-broadley/" target="_blank" rel="noreferrer noopener">Dr. Michael Broadley</a> of University of Lorraine.



<h2 class="wp-block-heading" id="h-plate-tectonics-and-life-on-earth">Plate tectonics and life on Earth</h2>



A chemically constant interior simplifies models of atmospheric evolution because surface reservoirs can be traced back to a fixed deep source. 



It also suggests that catastrophic oxidation events were not required to set the stage for photosynthesis.



For plate tectonics, a stable redox budget means that slabs sinking today enter roughly the same environment as their ancient counterparts. 



That constancy helps seismologists interpret <a href="https://www.earth.com/news/fresh-lava-from-deep-earth-mantle-pulses-burst-onto-land-where-new-ocean-is-forming/">deep‑Earth</a> images without invoking hidden chemical layers.



<h2 class="wp-block-heading" id="h-earth-s-mantle-still-holds-mysteries">Earth's mantle still holds mysteries</h2>



Researchers now want to know whether small pockets of iron‑rich melt lurk near the <a href="https://www.earth.com/news/ringwoodite-mineral-confirms-vast-ocean-exists-400-miles-under-earths-crust/">core‑mantle boundary</a> and how they affect heat flow. 



Upcoming experiments that combine synchrotron X‑rays with electrical measurements aim to pin down the conductivity of iron‑bearing bridgmanite at even higher temperatures.



Another open issue is how water cycles through Earth's deep mantle without altering its oxidation state, a puzzle that links deep‑Earth chemistry to ocean volumes over geologic time. 



Answers will refine our picture of a planet that, deep inside, appears to have kept the same recipe since birth.



The study is published in <a href="https://www.nature.com/articles/s41561-025-01725-0" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>.



-----



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Earth's mantle chemistry has remained stable for billions of years, according to scientists

New high‑pressure experiments show that the chemical recipe of Earth's...

Virginia faces a stubborn enemy: the spotted lanternfly (SLF). These invasive insects damage trees, crops, and gardens by feeding on plant sap and leaving behind sticky honeydew. A research team led by Assistant Professor Scotty Yang at Virginia Tech has discovered an unexpected helper in the battle against this pest: ants.



Yang and his team found that ants, drawn to honeydew, can carry traces of lanternfly DNA in their bodies. By analyzing the ants, scientists can now detect whether the <a href="https://www.earth.com/news/fish-swim-in-schools-by-stacking-like-ladder-rungs/">pest</a> has reached an area, even without spotting the insect directly.



<h2 class="wp-block-heading" id="h-ants-collect-lanternfly-dna-through-waste">Ants collect lanternfly DNA through waste</h2>



The research is based on environmental DNA, or eDNA. This approach collects genetic material that organisms leave behind in their surroundings. 



Spotted lanternflies leave DNA in their sugary waste, which ants readily consume. Scientists then apply a lab technique called polymerase chain reaction, or PCR, to identify SLF DNA inside the ants.



“Ants are nature’s sugar seekers,” Yang said. “If there’s even a tiny drop of honeydew left behind by a spotted lanternfly, ants are likely to find it.”



Yang’s team named the method “antDNA.” Even a single meal of honeydew lets <a href="https://www.earth.com/news/swarm-intelligence-ants-can-anticipate-obstacles-and-plan-ahead/">ants</a> retain the lanternfly's DNA for up to five days. Because ants roam widely, this method can detect SLF activity from as far as 100 meters from the infestation.



<h2 class="wp-block-heading" id="h-field-tests-across-virginia">Field tests across Virginia</h2>



Researchers tested the method at three Virginia sites: Salem, Lynchburg Site 1, and Lynchburg Site 2. These locations represented low, medium, and high lanternfly densities. 



At each site, they placed honey-baited lure stations along transects, attracting ants with cotton balls soaked in honey.



The Salem site showed a 46.7 percent positive rate for SLF DNA. Lynchburg Site 1 and Site 2 showed 62.1 percent and 62.5 percent, respectively. Most stations attracted ants within 30 minutes, proving the method’s ease of use.



The study also tested ants from nine species. SLF DNA was found even in ants that had not directly fed on honeydew, likely due to food sharing within <a href="https://www.earth.com/news/selfish-dna-in-a-few-ants-can-change-the-behavior-of-the-entire-colony/">colonies</a>. This behavior, known as trophallaxis, helps spread the DNA signal among nestmates.



<h2 class="wp-block-heading" id="h-ants-outperform-other-lanternfly-detectors">Ants outperform other lanternfly detectors</h2>



The antDNA technique works across landscapes and does not depend on the pest being visible. Unlike other methods, it does not require water, filtration, or special storage. Ants can be preserved in ethanol without refrigeration, reducing the burden on field teams.



Ants are present in nearly every habitat, from forests to cities. The collection setup is simple and inexpensive. The ants’ ability to hold liquid in their crop allows the DNA to stay detectable longer than in typical surface samples. 



The study confirmed that DNA from honeydew lasts longer than DNA from insect tissue, making honeydew a more stable source.



<h2 class="wp-block-heading" id="h-importance-of-early-detection">Importance of early detection</h2>



Spotted lanternflies harm many plants, including grapevines, hardwoods, and hops. As they feed, they weaken plants and coat them in honeydew. This sticky substance promotes sooty mold, which further harms plant health. 



Early detection is critical because removing the pest becomes harder once it spreads. Current surveillance efforts rely on human sightings of the insect or its egg masses. These sightings often occur only when the population has already grown. 



The ant surveillance method allows early detection of lanternfly species even in low-density zones and inaccessible areas.



<h2 class="wp-block-heading" id="h-scaling-up-and-looking-forward">Scaling up and looking forward</h2>



Yang and his team are now working on a portable test kit for use in the field. This will allow real-time molecular testing without needing a full lab. Faster results mean quicker action against the pest.



“One of the biggest advantages of using ants is that they live almost everywhere, such as forests, farms, cities - you name it,” Yang said. “Their constant search for food makes them ideal frontline samplers for spotted lanternfly DNA.”



This approach offers a new way to watch for invasive species like lanternflies using ants, without depending on visual surveys. It opens up possibilities for surveillance that is fast, flexible, and low-cost.



<h2 class="wp-block-heading" id="h-ants-may-detect-other-pests-like-lanternflies">Ants may detect other pests like lanternflies</h2>



The method could be expanded to track other pests. Many <a href="https://www.earth.com/news/how-many-ants-live-on-earth-at-any-point-in-time-total-number-is-astounding/">insects</a> excrete honeydew, and ants can pick up their DNA too. This opens the door for broader pest detection strategies using the same principle.



Ants, in their natural role as sugar hunters, may become an essential part of protecting crops, forests, and native ecosystems. With antDNA, researchers are tapping into nature’s own behaviors to find smarter ways of monitoring invasive threats.



The study is published in the journal <a href="https://scijournals.onlinelibrary.wiley.com/doi/10.1002/ps.8814" target="_blank" rel="noreferrer noopener">NeoBiota</a>.



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How ants could help stop the tree-killing lanternfly

Virginia faces a stubborn enemy: the spotted lanternfly (SLF). These...

In the wild, social lives shape survival. For female chimpanzees, bonds with others aren't just emotional glue. They are critical for keeping babies alive. 



A new study of wild eastern chimpanzees in Gombe National Park finds that social integration predicts whether a newborn survives, even when no close kin is around.



<h2 class="wp-block-heading" id="h-chimpanzees-with-strong-social-bonds">Chimpanzees with strong social bonds</h2>



Female <a href="https://www.earth.com/news/laughter-lifts-bonobo-moods-offering-clues-to-human-emotion/">chimps</a> are often the ones who leave their birth group. That means most do not live near their mothers or sisters. Still, those who manage to build friendships with other females raise more babies to weaning age.



“In species where females live in groups with their sisters and mothers, it’s less surprising that female sociality is beneficial,” said <a href="https://scholars.duke.edu/person/joseph.feldblum" target="_blank" rel="noreferrer noopener">Joseph Feldblum</a>, lead author and research professor at Duke. 



“But female chimps don’t usually have that. They are also less gregarious than males, so the fact that forming strong social connections still matters is striking.”



<h2 class="wp-block-heading" id="h-babies-of-social-chimpanzees">Babies of social chimpanzees </h2>



The team analyzed 37 years of detailed records from 37 mothers and 110 offspring. Using a composite sociality index (CSI), they tracked how much time females spent associating or grooming others before giving birth.



Their best model showed that higher CSI scores, especially with other <a href="https://www.earth.com/news/baby-talk-may-explain-what-sets-humans-apart-from-apes/">females</a>, greatly increased infant survival to age one and even to age five. The effect held even after excluding mothers who died shortly after giving birth.



A female with a CSI score twice the average had a 95 percent chance of her baby surviving the first year. For those below average, this dropped to 75 percent. 



Among females without any close kin, the trend was stronger. A single unit rise in sociality increased survival odds by over 17 times.



<h2 class="wp-block-heading" id="h-kinship-and-male-alliances">Kinship and male alliances </h2>



The researchers ran extra tests to see if the benefit was just from living with relatives. It was not. They also checked if relationships with <a href="https://www.earth.com/news/from-rumbles-to-rituals-scientists-map-the-cultures-of-the-animal-kingdom/">males</a> helped. That also came up short.



“That tells us it’s not just about being born into a supportive family,” said Feldblum. “These are primarily social relationships with non kin.”



Even when female kin were present, they had no direct effect on offspring survival. Instead, they raised the chance that a mother had strong friendships. But it was those friendships, not the family ties, that made the difference.



<h2 class="wp-block-heading" id="h-social-ties-remain-stable-over-time">Social ties remain stable over time</h2>



The benefits of bonding were not a one time fluke. Females who were social before birth stayed social after birth too. Their social worlds remained steady. 



“Our results don’t prove causation, but they point to the value of being surrounded by others who support you, or at least tolerate you,” said Feldblum.



This was not the case for bonds with males. Social connections between male and female chimpanzees were less stable and showed no link to baby survival.



<h2 class="wp-block-heading" id="h-social-bonds-and-chimpanzee-babies">Social bonds and chimpanzee babies </h2>



How do these friendships help? The exact mechanism remains uncertain. Social bonds might protect chimpanzee mothers from aggression. They could mean better access to food. Friendships might even prevent infanticide.



Earlier studies in this same group of chimps estimated that infanticide by other females may cause 3.5 percent to 19 percent of deaths in the first year. <a href="https://www.earth.com/news/social-curiosity-starts-young-and-helps-us-survive/">Social</a> mothers may face less of that risk.



More research is needed, but one thing is clear. Socially connected females stay in better shape, which could boost prenatal health. Unlike rank or dominance, which did not correlate with survival during this study window, sociality kept its value.



<h2 class="wp-block-heading" id="h-social-chimps-mirror-humans">Social chimps mirror humans</h2>



Though females often move away from family, they form lasting ties with unrelated females. The Gombe chimps mirror women in human patrilocal societies, who build networks after moving for marriage.



“We humans are remarkably collaborative and cooperative. We cooperate at scales that are pretty much unique in the animal kingdom,” said Feldblum. 



“Human females who don’t have access to kin, for example because they moved to a new city or village, are still able to form strong bonds that can benefit them.”



This study adds to the growing body of evidence that friendship matters. In baboons, dolphins, and horses, social bonds also improve reproductive success. In chimps too, strong bonds give babies a better chance at life.



Studying these dynamics in our closest relatives helps us understand our own nature. Like chimps, human survival does not just depend on strength or status. It depends on others. 



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S2589004225011241" target="_blank" rel="noreferrer noopener">iScience</a>.



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Babies of social chimpanzee mothers are more likely to survive

In the wild, social lives shape survival. For female chimpanzees,...

In a fascinating new study, scientists documented 34 attempts by wild killer whales to give food to humans. These rare cases spanned four oceans and 20 years. Some happened near boats, others in open water or even from the shore. 



The events highlight the <a href="https://www.earth.com/news/killer-whales-use-kelp-to-massage-and-groom-each-other/">orcas</a>’ possible interest in humans and raise important questions about whale intelligence, communication, and social behavior.



“Orcas often share food with each other - it’s a prosocial activity and a way that they build relationships with each other,” said study lead author Jared Towers, of <a href="https://baycetology.org" target="_blank" rel="noreferrer noopener">Bay Cetology</a> in British Columbia, Canada. “That they also share with humans may show their interest in relating to us as well.”



<h2 class="wp-block-heading" id="h-what-orcas-gave-humans">What orcas gave humans</h2>



The 34 incidents involved six distinct populations of killer <a href="https://www.earth.com/news/ai-helps-humans-have-20-minute-conversation-with-humpback-whale-named-twain/">whales</a>. They offered humans a total of 18 species: six fish, five mammals, three invertebrates, two birds, one reptile, and even one piece of seaweed.



In 97 percent of these cases, the orcas waited for a human response. Some hovered for several minutes. 



On several occasions, they tried again when the humans ignored or returned the offering. In two especially curious cases, whales retrieved birds after humans returned them, only to offer them again.



This behavior could be a form of interspecies curiosity, communication, or even social learning. As the authors suggest, these events might represent "generalized altruism" - an advanced trait observed in only a few social animals.



<h2 class="wp-block-heading" id="h-exploration-more-than-play">Exploration more than play</h2>



Though play was observed in 38 percent of the interactions, the researchers argue most cases were not playful. The age of the whales varied widely, and many offered whole, fresh prey. 



In over 75 percent of ignored cases, the whales later used the prey for themselves or their group. This suggests the offerings had purpose and value, not just entertainment.



Curiosity-driven behavior, distinct from play, seemed a stronger motivator. As the study explains, animals often explore to reduce uncertainty. 



Offering food to humans might help orcas learn how we respond, just as they would with unfamiliar members of their own <a href="https://www.earth.com/news/whales-blow-bubble-smoke-rings-near-humans-to-communicate/">species</a>.



<h2 class="wp-block-heading" id="h-deep-social-intelligence-at-work">Deep social intelligence at work</h2>



Some whales returned the same item to humans multiple times. Others acted in pairs or small groups. 



Most of the 34 events involved a single whale separating from a larger group. This suggests the act was not for show. Rather, it might reflect the whale's individual decision to interact.



Interestingly, killer <a href="https://www.earth.com/news/how-dolphin-brains-evolved-to-see-underwater-by-using-sound-echolocation/">whales</a> have also been documented cooperating with human fishers in places like Australia and Russia. The authors noted that this history could influence modern interactions, especially as human activity increases near their habitats.



<h2 class="wp-block-heading" id="h-whales-may-view-humans-as-companions">Whales may view humans as companions</h2>



Killer whales rank second only to humans in brain-to-body ratio. They also show advanced emotional and social behavior. 



These traits support complex social learning, reciprocal behavior, and possibly even empathy.



“Offering items to humans could simultaneously include opportunities for killer whales to practice learned cultural behavior, explore or play and in so doing learn about, manipulate or develop relationships with us,” the researchers wrote.



<h2 class="wp-block-heading" id="h-humans-should-not-approach-whales">Humans should not approach whales</h2>



Despite the remarkable nature of these encounters, the researchers urge caution. Orcas can show complex and sometimes unpredictable behavior. 



While no wild killer whale has killed a person, some interactions have been intense. They warn against seeking out such encounters or encouraging the behavior without proper permissions.



Most of these whales belonged to populations that hunt near the surface and share prey frequently. 



No deep-water, fish-only populations were involved. This suggests that cooperative surface hunting may lead to more frequent and visible interspecies interactions.



<h2 class="wp-block-heading" id="h-complex-minds-of-whales-and-humans">Complex minds of whales and humans</h2>



The findings challenge our assumptions about human-animal relationships. If orcas are experimenting with ways to relate to us, it means they recognize us not as threats, but as potential social partners.



These whales are not just predators. They are thinkers, observers, and maybe, in some way, explorers of culture, curiosity, memory, learning, and emotion. 



Their actions suggest complex minds in both whales and humans, capable of choice, empathy, and communication.



The study is published in the <a href="https://psycnet.apa.org/fulltext/2026-29805-001.html" target="_blank" rel="noreferrer noopener">Journal of Comparative Psychology</a>. 



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Killer whales may be trying to bond with humans

In a fascinating new study, scientists documented 34 attempts by...

Before you make a decision, your brain is already busy. It starts pulling in evidence, thinking through options, and slowly leaning toward a choice - all without you even realizing it.



Take a simple situation: two drivers in rush hour traffic. They both see the same congested road. One hits the gas to merge. The other taps the brakes and waits. 



Same scene, different reaction. Why? That’s a question that scientists have been trying to answer for years.



<h2 class="wp-block-heading" id="h-decision-making-in-the-brain">Decision-making in the brain</h2>



Researchers from <a href="https://www.princeton.edu/">Princeton University</a>, working with teams from Cold Spring Harbor Laboratory, Stanford University, and Boston University, may be closer to cracking the code. 



The study was focused on how individual brain cells - each with its own quirks - somehow work together to land on a decision. In particular, the team investigated the dorsal <a href="https://www.earth.com/news/two-distinct-maps-discovered-in-the-brain/">premotor cortex</a> - a part of the brain that helps turn decisions into actions. 



When we choose to reach, move, or act, the dorsal premotor cortex is in play. But it’s not as simple as one neuron equals one thought. The activity here is all over the map.



The researchers trained <a href="https://www.earth.com/news/brain-structure-of-rhesus-macaques-is-shaped-by-social-interactions/">rhesus macaques</a> to look at a checkered screen and figure out whether red or green was more dominant. Sometimes the answer was obvious, while other times it was tough to call.



<h2 class="wp-block-heading" id="h-signals-from-individual-neurons">Signals from individual neurons </h2>



While the monkeys made their choices, the scientists recorded signals from individual neurons. 



The researchers found that even during the same trial, the neurons didn’t behave in sync. The monkeys showed a wide range of responses, something scientists call “heterogeneity.”



Dr. Tatiana Engel, an associate professor at the Princeton Neuroscience Institute, is the senior author of the study.



“The widespread assumption is that this heterogeneity reflects the complex dynamics involved in cognition,” said Dr. Engel. "But surprisingly, we found that this apparent complexity arises from a very different neural coding principle.”



<h2 class="wp-block-heading" id="h-neurons-work-together-for-a-decision">Neurons work together for a decision </h2>



The team developed a new type of computational model to help explain this complexity. It revealed that a neuron's behavior is shaped by two key factors. 



The first is tuning - when a neuron responds and what kind of decision it reacts to. The second is neural dynamics - how the brain’s internal state influences that activity as it unfolds over time.



Imagine a rolling landscape. In this model, valleys represent stable decisions. As <a href="https://www.earth.com/news/first-complete-map-of-every-neuron-in-the-brain-revealed/">neurons</a> activate, their patterns move like a ball rolling down a hill. 



On steeper slopes (easier choices), the ball moves quickly toward a clear answer. On flatter ground (harder decisions), the ball wobbles more, making mistakes more likely.



<h2 class="wp-block-heading" id="h-a-coordinated-journey-in-the-brain">A coordinated journey in the brain</h2>



When the team compared this model to real brain data, it held up. The tuning stayed the same no matter how easy or hard the task was, but the shape of the mental terrain shifted. 



That shift helped explain why neurons that look random on the surface are actually following the same deeper logic.



“Think of it like a group of skiers descending a mountain,” explained Dr. Engel. “Each prefers a slightly different path, but all are shaped by the same slope beneath them."



"Similarly, each neuron has its own preference and activity, but the group of cells collectively in the premotor cortex takes a coordinated journey and gradually settles into a stable state that represents the decision.”



<h2 class="wp-block-heading" id="h-why-this-matters-beyond-the-lab">Why this matters beyond the lab</h2>



The study helps decode how the brain works when we’re weighing choices, especially the tricky ones. That kind of insight is crucial - not just for understanding everyday decision-making, but for understanding mental health disorders.



In conditions like <a href="https://www.earth.com/news/schizophrenia-linked-to-irregular-fatty-metabolism-in-the-brain/">schizophrenia</a> or <a href="https://www.earth.com/news/high-fructose-intake-may-contribute-to-bipolar-disorder-and-aggression/">bipolar disorder</a>, decision-making can be disrupted. Knowing how neurons usually coordinate could help pinpoint what’s going wrong. It also opens the door to designing more targeted therapies that focus on decision-related brain activity.



The team isn’t done yet. Their next step is to dig deeper into the roles of different types of neurons and how their connections shape this internal landscape.



“Every decision is unique,” said Dr. Engel. “But by digging down to the level of single trials and single neurons, we can start to make sense of it.”



The full study was published in the journal <a href="https://www.nature.com/articles/s41586-025-09199-1">Nature</a>.



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How your brain makes a decision before you know it

Before you make a decision, your brain is already busy....

A single fertilized egg somehow manages to build skin, brain, and blood cells within a matter of days. But how do those first cells know which body parts to build? How do some cells know to create kidneys while other cells immediately start creating skin? 



Solving that puzzle has kept developmental biologists busy for more than a century, yet many lineage maps still look like unfinished sketches. 



Now an Australian team reports a tracking tool called LoxCode that labels every cell in a mouse embryo with a unique DNA tag and follows its descendants as tissues form. 



“This creates a trackable barcode, allowing us to peer inside this fundamental process with unprecedented detail,” said <a href="https://findaresearcher.wehi.edu.au/weber.ts" target="_blank" rel="noreferrer noopener">Dr. Tom Weber</a> of the <a href="https://www.wehi.edu.au/" target="_blank" rel="noreferrer noopener">Walter and Eliza Hall Institute</a>.



<h2 class="wp-block-heading" id="h-loxcode-tracks-each-cell-from-the-start">LoxCode tracks each cell from the start</h2>



LoxCode relies on the Cre recombinase enzyme to shuffle short DNA cassettes, generating more than 30 billion possible <a href="https://www.nature.com/articles/s41576-023-00624-7" target="_blank" rel="noreferrer noopener">barcodes</a> in a single step. 



Each label is copied faithfully as the embryo grows, so scientists can reconstruct family trees later by simple sequencing.



In pilot tests, the team injected the barcode cassette on day 5.5 of pregnancy, when the <a href="https://www.sciencedirect.com/topics/neuroscience/epiblast" target="_blank" rel="noreferrer noopener">epiblast</a> is still arranging its first germ layers. A week later they recovered fetuses and read the tags in bulk tissue and at single‑cell resolution.



“That tells us fate bias appears far earlier than textbooks suggest,” explained <a href="https://www.wehi.edu.au/researcher/shalin-naik/" target="_blank" rel="noreferrer noopener">Prof. Shalin Naik</a>, a laboratory head at WEHI. Some clones reached every corner of the embryo, while others stuck to ectoderm, blood, or limb buds.&nbsp;



By feeding the barcode data into an agent‑based model, the researchers predicted hidden asymmetries, like left‑versus‑right kidney precursors, and then confirmed them experimentally. 



Such computational cross‑checks strengthen confidence that the tags truly record biology, not sequencing noise.



<h2 class="wp-block-heading" id="h-how-loxcode-writes-billions-of-labels">How LoxCode writes billions of labels</h2>



Earlier <a href="https://www.science.org/doi/10.1126/science.aaf7907" target="_blank" rel="noreferrer noopener">lineage tracing</a> systems depended on viruses or CRISPR cuts, which can damage cells or miss subtle branches. One <a href="https://www.nature.com/articles/s41586-022-04994-6" target="_blank" rel="noreferrer noopener">CRISPR</a> recorder captured only a few hundred unique edits across a whole zebrafish, limiting resolution.



LoxCode gets around previous limitations by using 13 short pieces of DNA, arranged so that an enzyme called <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/cre-recombinase" target="_blank" rel="noreferrer noopener">Cre recombinase</a> can shuffle them in many different ways. Once the pieces reach a smaller, stable size, the shuffling stops, locking the DNA tag in place for each cell.



Since each DNA piece is very short, these tags are easy to read using standard genetic sequencing tools. That makes the method affordable, even for labs without large budgets.



The team also created a special breed of mouse, called strain 037677, which is available from <a href="https://www.jax.org/" target="_blank" rel="noreferrer noopener">The Jackson Laboratory</a>. Researchers can use it by pairing it with another mouse that activates the barcoding process in specific tissues.



<h2 class="wp-block-heading" id="h-revealing-hidden-bias-in-the-embryo">Revealing hidden bias in the embryo</h2>



<a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC4699068/" target="_blank" rel="noreferrer noopener">Pluripotent cells</a> were long assumed to wait for external signals before picking a destiny. Yet the new data show many clones already lean toward one germ layer while the fetus is still the size of a poppy seed.



For instance, epiblast cells sitting near the forming early streak produced mostly blood and mesenchyme cells, matching earlier dye‑label <a href="https://www.nature.com/articles/nbt.4103" target="_blank" rel="noreferrer noopener">studies</a> but adding single‑cell resolution.



Conversely, anterior clones favored neural tissues, hinting that position cues translate into lineage bias before gastrulation starts.



Unexpected asymmetries emerged too. The left limb bud often traced back to different founders than the right, suggesting randomness, not mirror symmetry, seeds the first skeletal blueprint.



Such insights could clarify why some <a href="https://www.earth.com/news/cellular-cleanup-helps-preserve-eggs-and-fertility/">congenital disorders</a> strike only one side of the body. LoxCode also gives stem‑cell engineers reference maps for guiding organoids toward balanced growth.



<h2 class="wp-block-heading" id="h-from-brain-growth-to-stroke-repair">From brain growth to stroke repair</h2>



Because barcoding works in live mice, investigators are already adapting it to study immune development, gut regeneration, and tumor relapse. 



A neuroscientist at the <a href="https://www.uq.edu.au/" target="_blank" rel="noreferrer noopener">University of Queensland</a> is tracing how newborn neurons integrate into adult circuits after a stroke, using LoxCode to mark progenitors at the injury edge.



Cancer biologists plan to follow how therapy‑resistant clones emerge over months of drug exposure. By back‑tracking each surviving cell to its earliest barcode, they hope to spot vulnerabilities before relapse.



Drug developers could one day screen compounds that push harmful lineages back toward healthy fates. That approach pairs naturally with <a href="https://www.earth.com/news/rna-breakthrough-sheds-light-on-the-beginning-of-life/">single‑cell RNA</a> profiles, revealing not just where a clone goes but how its gene programs shift along the journey.



<h2 class="wp-block-heading" id="h-what-this-means-for-medicine">What this means for medicine</h2>



Developmental disorders often arise from mis‑timed cell decisions that happen weeks before clinical symptoms. 



With a cellular ancestry chart in hand, researchers can pinpoint the first wrong turn and design precise interventions.



<a href="https://www.earth.com/news/vitamin-c-promotes-skin-renewal-and-anti-aging-at-the-genetic-level-dna-demethylation/">Gene therapies</a> that swap faulty DNA in founder cells might correct an entire lineage instead of treating tissues piecemeal. 



Similarly, transplant doctors could verify that lab‑grown grafts contain the right mixture of cell types before surgery.



Ethical questions will follow, especially if human embryos are ever tagged at comparable depth. For now, the focus stays on mice, where LoxCode already promises to rewrite textbooks on early embryonic patterning.



The study is published in the journal <a href="https://linkinghub.elsevier.com/retrieve/pii/S0092867425004611" target="_blank" rel="noreferrer noopener">Cell</a>.



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How do your cells know which parts of your body to build? Brilliant new tech is helping us find out

A single fertilized egg somehow manages to build skin, brain,...

Bird feeding is a cherished pastime across many cultures. Whether it’s scattering breadcrumbs near a city pond or hanging feeders outside suburban windows, millions of people engage in acts of casual care for wild birds. 



Recent research from the <a href="https://www.uark.edu" target="_blank" rel="noreferrer noopener">University of Arkansas</a> reveals that what we feed birds can deeply affect how they handle disease.



The study revealed that canaries on high-protein diets developed stronger immune profiles and milder symptoms when infected with Mycoplasma gallisepticum (MG), a pathogen common in wild <a href="https://www.earth.com/news/hundreds-of-bird-species-could-vanish-in-the-next-century/">songbirds</a>.



“Our results are exciting because of the importance of human supplemented food in wildlife disease systems, especially wild birds, which are commonly provided with supplemental food via bird feeders,” said Erin Sauer, lead author of the study.



This research is the first to link diet with molecular-level immune differences in wildlife. It focuses on how food type - not just quantity - shapes disease outcomes in birds.



<h2 class="wp-block-heading" id="h-protein-fed-birds-recover-faster">Protein-fed birds recover faster</h2>



The researchers divided canaries into two groups. One group received a high-protein diet made mostly of egg whites, while the other received a high-fat diet with more yolk and oil. Birds were then exposed to the MG pathogen or given a harmless placebo.



Before infection, protein-fed <a href="https://www.earth.com/news/bird-evolution-timeline-pushed-back-20-million-years-by-baminornis-zhenghensis-discovery/">birds</a> already showed increased expression of immune-related genes. After infection, lipid-fed birds had to ramp up their immune systems, while protein-fed birds maintained steady, high-level expression. This shows their immune systems were already ready.



Protein-fed birds recovered faster. Their eye inflammation - a symptom of MG - was lower and cleared quicker. Lipid-fed birds took longer to recover, with more prolonged symptoms.



<h2 class="wp-block-heading" id="h-immune-gene-activity-before-infection">Immune gene activity before infection</h2>



The team used RNA sequencing to analyze gene activity. Before infection, protein-fed <a href="https://www.earth.com/news/birds-are-struggling-to-keep-pace-with-a-warming-climate/">birds</a> had 267 genes upregulated related to immune defense. 



Lipid-fed birds had 248 different genes upregulated, many tied to basic cellular functions like ribosome activity, not immunity.



After infection, the contrast grew. Lipid-fed birds showed over 1,000 genes with significant changes. Protein-fed birds had only 66 such genes. 



This means lipid-fed birds had to drastically adjust their systems during infection. Protein-fed birds needed little change - they were already prepared.



Surprisingly, immune genes like JCHAIN (linked to antibody production) were seven times more active in protein-fed birds before infection. Lipid-fed birds only caught up after infection, suggesting delayed immune readiness.



<h2 class="wp-block-heading" id="h-metabolic-clues-and-broader-implications">Metabolic clues and broader implications</h2>



Diet also influenced energy-related genes. Lipid-fed birds showed signs of stress in genes tied to mitochondrial function and insulin regulation. 



One gene, LEPR (leptin receptor), responded in opposite ways between the two groups. This points to broader metabolic differences that could influence disease tolerance.



These molecular effects mirror patterns seen in wild house finches that have evolved tolerance to MG. This suggests that simple dietary changes can mimic the effects of natural selection.



<h2 class="wp-block-heading" id="h-what-backyard-bird-lovers-can-do">What backyard bird lovers can do</h2>



So what can people feeding backyard <a href="https://www.earth.com/news/birds-may-be-using-quantum-physics-for-migration/">birds</a> take from this study?



Sauer suggests giving birds high-protein and nutrient-dense options. These include suet with seeds, mealworms, peanuts, and sunflower seeds. These foods support birds’ immune systems and overall condition.



Avoid feeding mostly cracked corn, millet, or bread. These offer limited nutritional value. Still, birds may need more fat during winter or migration, so balance matters. Birds will often choose what they need most.



<h2 class="wp-block-heading" id="h-protein-can-boost-birds-survival">Protein can boost birds' survival</h2>



This study shows that everyday actions, like feeding birds, can directly impact their survival and overall health. While feeding may seem harmless or routine, the type of food offered plays a critical role. 



Poor-quality food can weaken birds' immune systems, making them less able to fight infections and recover from illness.



As human activity continues to reshape natural landscapes and spread disease more widely, our role in supporting wildlife becomes even more important. 



The research reminds us that meaningful change often begins with small, consistent habits. Offering nutrient-rich, protein-balanced food helps birds stay strong, boost immunity, and recover faster when sick or stressed.



Even simple choices at backyard feeders, such as selecting better ingredients, can strengthen birds’ natural defenses. These actions become a powerful way to support bird populations. 



The study is published in the journal <a href="https://onlinelibrary.wiley.com/doi/10.1111/mec.17793" target="_blank" rel="noreferrer noopener">Molecular Ecology</a>.



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Protein helps birds prepare to fight off infection

Bird feeding is a cherished pastime across many cultures. Whether...

Giant,Male,Cuttlefish,With,Stripe,Tentacles

When we imagine the ancient oceans, we often picture massive reptiles and shelled ammonites dominating the waters. For decades, paleontologists believed these creatures ruled the Mesozoic Era without much competition. 



However, a new study from Hokkaido University&nbsp;challenges that idea by revealing the unexpected dominance of <a href="https://www.earth.com/news/how-squid-power-their-amazing-camouflage-abilities/">ancient</a> squids.



<h2 class="wp-block-heading" id="h-understanding-squids-the-basics">Understanding squids - the basics</h2>



Squids are remarkable marine invertebrates belonging to the class <a href="https://www.earth.com/news/octopus-and-squid-senses-linked-to-human-brain-evolution/">Cephalopoda</a>, which they share with octopuses and cuttlefish. Their biology showcases some of nature’s most fascinating adaptations. 



Squids possess a mantle cavity for jet propulsion, using rapid water expulsion to move with precision and speed. Their large, complex eyes rival those of vertebrates, providing excellent vision crucial for detecting predators and prey in the dimly lit depths. 



Internally, they have a beak-like jaw and a radula for processing food, typically fish and crustaceans. One of their most iconic features is their ability to release ink, a defense mechanism that creates a smokescreen, enabling a quick escape.



Behaviorally, squids exhibit <a href="https://www.earth.com/news/scientists-unlock-the-light-bending-secrets-of-squid-skin/">sophisticated camouflage</a> through chromatophores - pigment-filled cells controlled by the nervous system - that allow them to change color almost instantly. Some species also display bioluminescence via symbiotic bacteria or light-producing organs.



<h2 class="wp-block-heading" id="h-studying-squids-with-fossil-rocks">Studying squids with fossil rocks</h2>



The research shows that squids were already dominant ocean predators 100 million years ago. This changes what scientists believed about life in ancient seas.



The team used a new technique to scan <a href="https://www.earth.com/news/living-baby-colossal-squid-captured-on-video-for-the-first-time-ever/">fossil</a> rocks. They fully digitized the rocks in 3D without breaking them open. This helped them find over 1,000 fossilized beaks of ancient cephalopods. 



Out of these, 263 were from squids. About 40 of those belonged to species that scientists had never seen before.



<h2 class="wp-block-heading" id="h-squids-rarely-leave-fossils">Squids rarely leave fossils</h2>



Squids have soft bodies that decay quickly after death. Unlike animals with bones or shells, they leave behind very little for scientists to find. 



This makes it hard to trace their history through fossils. However, squids have tough beaks, which they use like jaws to catch and eat prey. These beaks are strong enough to survive over millions of years in rock.



Cephalopods, the group that includes squids, <a href="https://www.earth.com/news/octopuses-could-dominate-earth-if-humans-vanish/">octopuses</a>, and <a href="https://www.earth.com/news/cuttlefish-have-passed-marshmallow-test-designed-for-kids-proving-cephalopods-intelligence/">cuttlefish</a>, have existed for about 500 million years. But it’s been difficult for scientists to figure out exactly when squids first appeared and how they changed over time.



Because full squid <a href="https://www.earth.com/news/new-species-of-deep-sea-squid-discovered-that-broods-giant-eggs/">fossils</a> are rare, researchers have had limited evidence to work with. This study changes that. 



By finding hundreds of ancient squid beaks in 100-million-year-old rocks, scientists now have solid proof that squids were already present and had formed many different species. It fills in a major gap in our understanding of their ancient history.



<h2 class="wp-block-heading" id="h-ancient-squids-dominated-the-ocean">Ancient squids dominated the ocean</h2>



The researchers found more squid fossils than those of ammonites and bony fish. That came as a surprise. Ammonites had shells and were thought to be the most successful swimmers of the Mesozoic era.



“In both number and size, these <a href="https://www.earth.com/news/squid-mating-tactics-are-determined-by-birth-date/">ancient</a> squids clearly prevailed the seas,” said Dr. Shin Ikegami of the Department of Earth and Planetary Sciences at Hokkaido University, the study’s first author. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/06/squids_dominated-oceans_100-million-years-ago_grinding-tomography_Ikegami_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/06/squids_dominated-oceans_100-million-years-ago_grinding-tomography_Ikegami_1s.webp" alt="The digital fossil-mining method utilizes grinding tomography to create digitized rocks and reveal hidden fossils within them. Credit: Ikegami et al., Science" class="wp-image-1975747"/></a><figcaption class="wp-element-caption">The digital fossil-mining method utilizes grinding tomography to create digitized rocks and reveal hidden fossils within them. Click image to enlarge. Credit: Ikegami et al., Science</figcaption></figure>



“Their body sizes were as large as fish and even bigger than the ammonites we found alongside them. This shows us that squids were thriving as the most abundant swimmers in the ancient ocean.”



<h2 class="wp-block-heading" id="h-modern-squids-in-ancient-oceans">Modern squids in ancient oceans</h2>



The study found that <a href="https://en.wikipedia.org/wiki/Myopsida" target="_blank" rel="noreferrer noopener">Myopsida</a> and <a href="https://en.wikipedia.org/wiki/Oegopsida" target="_blank" rel="noreferrer noopener">Oegopsida</a> squids existed 100 million years ago. These two groups are still present today. Myopsida live near the shore. Oegopsida live in the open ocean.



Earlier theories suggested ancient squids evolved rapidly after the extinction of the <a href="https://www.earth.com/news/where-did-dinosaurs-come-from-missing-fossils-hold-the-secret/">dinosaurs</a>. That extinction happened 65 million years ago. But this study shows squids had already diversified long before that event.



<h2 class="wp-block-heading" id="h-early-apex-hunters">Early apex hunters</h2>



Associate Professor Yasuhiro Iba of the Department of Earth and Planetary Sciences at <a href="https://www.global.hokudai.ac.jp" target="_blank" rel="noreferrer noopener">Hokkaido University</a> led the study.



“These findings change everything we thought we knew about marine ecosystems in the past,” said Iba. “Squids were probably the pioneers of fast and intelligent swimmers that dominate the modern ocean.”



The new fossil data shows that squids had already taken important roles in the ocean. They were not just survivors. 



They were already key predators in their ecosystems. Their numbers, size, and early diversity support that conclusion.



<h2 class="wp-block-heading" id="h-rethinking-ocean-evolution">Rethinking ocean evolution</h2>



Squids are among the most active, adaptable, and intelligent invertebrates living in today’s oceans. They use complex behaviors, advanced movement, and sharp sensory skills to survive in both coastal and deep-sea environments. 



Because of their importance in modern <a href="https://www.earth.com/news/fishing-removes-key-nutrients-from-marine-ecosystems/">marine ecosystems</a>, understanding their origins can help scientists piece together the long history of ocean life.



By studying when ancient squids first appeared and how they spread into different habitats, researchers can trace the development of major evolutionary traits. These include fast swimming, hunting techniques, and even early signs of intelligence. 



Such insights also offer a clearer picture of how ancient marine ecosystems functioned and how they changed over time.



This new study provides strong evidence that many squid species were already established and thriving 100 million years ago - long before the mass extinction that ended the age of dinosaurs. 



Their presence was not small or recent. Instead, they played a major role in shaping ocean life far earlier than we previously believed.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adu6248" target="_blank" rel="noreferrer noopener">Science</a>.



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Squids dominated ancient oceans 100 million years ago

When we imagine the ancient oceans, we often picture massive...

Earth’s oceans keep long, detailed logs of climate change, and some of the best pages come from fusulines - shells smaller than a grain of sand. 



A recent study shows that these tiny record‑keepers flourished when the planet cooled yet nearly vanished, twice, when volcanic heat spiked global temperatures.



The work was led by Professor Shuzhong Shen of <a href="https://www.nju.edu.cn/en/" target="_blank" rel="noreferrer noopener">Nanjing University</a>. The research team stitched together 299 rock sections and 1,391 fossil <a href="https://www.earth.com/news/scientists-finally-confirm-species-identity-of-the-dragon-man-fossil-skull-denisovan/">species</a> to build an unusually sharp picture of past marine life.



<h2 class="wp-block-heading" id="h-fusulines-recorded-carbon-changes">Fusulines recorded carbon changes</h2>



The stars of the study are <a href="https://www.bgs.ac.uk/discovering-geology/fossils-and-geological-time/foraminifera/" target="_blank" rel="noreferrer noopener">foraminifera</a>, single‑celled protists that build carbonate shells. One order, Fusulinida, blanketed the seafloor from 344 million to 252 million years ago and behaved like “carbonate rock factories,” pumping out vast reefs as they grew.



Shen’s data reveal two bursts of diversification, one during late <a href="https://www.nationalgeographic.com/science/article/carboniferous" target="_blank" rel="noreferrer noopener">Carboniferous</a> cooling and another as the <a href="https://www.britannica.com/science/Permian-Period" target="_blank" rel="noreferrer noopener">Permian</a> began. 



The first wave produced small, simple shells; the second favored larger forms with honeycomb‑like walls that likely hosted photosynthetic <a href="https://www.earth.com/news/fossil-discovery-pushes-back-reptile-evolution-by-40-million-years/">partners</a>.



<h2 class="wp-block-heading" id="h-fusulines-declined-in-warm-spikes">Fusulines declined in warm spikes</h2>



When the climate <a href="https://www.science.org/doi/10.1126/science.aba6853" target="_blank" rel="noreferrer noopener">cooled</a>, glaciers locked up water, sea levels dropped, and new shallow habitats opened. Fusuline species counts tripled during that 40‑million‑year chill, echoing a pattern seen in later planktonic cousins during the Cenozoic cooling trend.



Warm pulses told a different story. The Kasimovian warming about 304 million years ago wiped out roughly 45 percent of fusuline species in less than one million years, and the curve plunged again as temperatures climbed between 294 million and 284 million years ago.



The end‑Permian supervolcano sealed their fate. During that episode, 59.5 percent of remaining species disappeared in a window shorter than the span between human <a href="https://www.earth.com/news/what-modern-fossils-will-be-the-most-surprising-to-future-explorers/">generations</a> today.



<h2 class="wp-block-heading" id="h-carbon-from-volcanoes-drove-extinctions">Carbon from volcanoes drove extinctions</h2>



Shen’s timeline lines up each extinction spike with a pulse of basalt from giant volcanic provinces such as Emeishan and Siberia. 



Those eruptions injected <a href="https://www.nature.com/articles/ngeo3031" target="_blank" rel="noreferrer noopener">carbon dioxide</a> fast enough to heat surface oceans by 5 to 10 °F, acidify seawater, and strip it of oxygen, a triple hit <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/benthic-organisms" target="_blank" rel="noreferrer noopener">benthic organisms</a> could not dodge.



Carbon‑isotope <a href="https://www.pnas.org/content/111/9/3316" target="_blank" rel="noreferrer noopener">data</a> show the oceans turned more acidic whenever the 87Sr/86Sr ratio dipped, a fingerprint of fresh volcanic rock weathering. 



At the same time, modeled oxygen levels dropped below the threshold needed to support large seafloor life - matching modern observations where foraminiferal diversity declines sharply in low-oxygen zones



<h2 class="wp-block-heading" id="h-orbital-cycles-mattered-less">Orbital cycles mattered less</h2>



Beyond the headline crashes, Shen’s team spotted weak but persistent <a href="https://science.nasa.gov/science-research/earth-science/milankovitch-orbital-cycles-and-their-role-in-earths-climate/" target="_blank" rel="noreferrer noopener">Milankovitch cycles</a>, grand wobbles in Earth’s orbit that last around two million and one million years. 



During the minima of those cycles, gentler seasons may have favored glacier growth and nutrient runoff, nudging speciation upward.



The cycles explain no more than ten percent of the diversity curve, yet their fingerprint is clear enough to remind us that even slow orbital nudges modulate life. 



Still, the sharpest rises and falls match rapid volcanic events, confirming that climate severity, not orbital pacing, set the main tempo.



<h2 class="wp-block-heading" id="h-carbon-rise-threatens-ocean-life-again">Carbon rise threatens ocean life again</h2>



“Mitigating climate change and protecting ecosystems is an urgent task of our time,” emphasized Professor Shen. The study’s most sobering line compares rates of <a href="https://www.earth.com/news/fossil-euarthropod-youti-yuanshi-lived-520-million-years-ago-insect-evolution/">ancient</a> warming with today’s rates.&nbsp;



Current <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC12060277/" target="_blank" rel="noreferrer noopener">human‑driven warming</a> runs at least ten times faster than the pace that eliminated fusulines, and modern reef‑building calcifiers already show stress in warmer, more acidic seas. 



If past is prologue, sustained greenhouse gas emissions could push today’s carbonate shell builders, corals, coccolithophores, large benthic foraminifera, toward the same cliff.



<h2 class="wp-block-heading" id="h-carbon-linked-extinction-cycles">Carbon-linked extinction cycles</h2>



To reach sub‑45,000‑year resolution, the team fed every first‑ and last‑appearance datum into a constrained‑optimization algorithm called <a href="https://www.nhm.uio.no/english/research/resources/past/help/conop.html" target="_blank" rel="noreferrer noopener">CONOP</a>. 



Supercomputers iterated millions of possible stratigraphic orders until the tightest fit emerged, turning scattered field data into a single high‑definition timeline.



Rarefaction tests showed that sampling gaps do not skew the pattern; three different resample sizes reproduced the same peaks and troughs. 



By filtering out trends longer than ten million years, the researchers isolated the shorter cycles that hint at orbital pacing.



<h2 class="wp-block-heading" id="h-the-rise-and-fall-of-fusulines">The rise and fall of fusulines</h2>



The experts then ran multivariate regressions against seven environmental proxies, from carbon isotopes to sea‑level curves. 



The best model, which combines carbon dioxide, seawater strontium, oxygen availability, and carbon isotopes, explains 81 percent of the diversity swings, leaving little doubt that physical climate set the rules of life and death for fusulines.



Fusulines vanished, but their story still speaks. They show that rapid warming can silence even dominant, resilient lineages, and they underline how cooling phases can seed explosive innovation.



Marine ecosystems today sit at a similar junction, with greenhouse gases climbing and volcanic analogs replaced by smokestacks and exhaust pipes. 



The fossil record offers no comfort that life can adapt at the speed we are forcing, but it does offer a clear warning.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.adv2549" target="_blank" rel="noreferrer noopener">Science Advances</a>.



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Tiny ocean creatures have always gone extinct during Earth's past climate warming periods

Earth’s oceans keep long, detailed logs of climate change, and...

We know the oceans are changing. But how have they changed over the last half-billion years? Until now, we had no clear measure of how the total mass of ocean life - not just its variety - has evolved over deep time. 



In a first-of-its-kind effort, scientists from <a href="https://www.stanford.edu/">Stanford University</a> measured how the biomass of marine organisms - the actual amount of living material in the ocean - has changed over the last 540 million years.



<h2 class="wp-block-heading" id="h-long-term-changes-in-ocean-life">Long-term changes in ocean life</h2>



The study shows a long-term trend of rising <a href="https://www.earth.com/news/deforestation-causes-biomass-loss-beyond-directly-affected-areas/">biomass</a>, with noticeable crashes during major extinction events. This pattern closely tracks with known increases in marine biodiversity, suggesting a deep link between how much life the ocean holds and how varied that life is.



Study lead author Pulkit Singh is a postdoctoral scholar in Earth and Planetary Sciences in the <a href="https://sustainability.stanford.edu/">Stanford Doerr School of Sustainability</a>.



“Understanding the amount of biomass is important because it represents key traits about an ecosystem that are not captured by the number of species or even the number of niches that they fill,” said Singh.



“But as we move into the past, our measurements of biomass are very limited, so that was the big gap in biological history we wanted to fill with our study.”



<h2 class="wp-block-heading" id="h-ocean-life-changes-across-history">Ocean life changes across history</h2>



Getting to this result took years of meticulous work. Singh and his team dug into data from over 7,700 marine limestone samples spanning hundreds of millions of years. 



The samples came from more than 100 published studies and Singh’s own data collection. Each rock was cut and polished into slices thin enough for light to pass through, then examined under a microscope. 



Using a method called petrographic point-counting, the researchers calculated what percentage of each sample was made up of skeletal remains - <a href="https://www.earth.com/news/fossilized-shells-can-help-predict-the-impacts-of-climate-change/">shells</a> from animals, certain algae, and single-celled protists.



It’s not just busywork. The amount of shell material in these rocks tells scientists how much living material existed at different points in Earth’s history. 



More shells in the ocean generally mean more <a href="https://www.earth.com/news/all-living-things-emit-a-subtle-glow-that-ceases-at-death/">living things</a>. And more life usually means more energy flowing through ecosystems - a strong signal of planetary health.



<h2 class="wp-block-heading" id="h-the-challenge-of-measuring-biomass">The challenge of measuring biomass </h2>



Tracking <a href="https://www.earth.com/news/global-biodiversity-crisis-is-actually-worse-than-we-thought/">biodiversity</a> through deep time has been part of science since the 19th century. But measuring biomass - the total amount of living material - is a much rarer effort. 



Measuring biomass demands massive amounts of data and offers no guarantee of a clear pattern.



“The first quantitative effort to document and graph biodiversity across geological time was made in 1860, but until Pulkit’s paper, there’s never been a corresponding biomass-across-time paper,” noted senior study author Professor Jonathan Payne. 



“I’m impressed by his intellectual courage to go and take a chance on a project like this.”



<h2 class="wp-block-heading" id="h-biomass-over-millions-of-years">Biomass over millions of years</h2>



The earliest rocks examined, from the Cambrian period about 540 million years ago, showed low shell content - under 10 percent on average. 



By the Ordovician, starting around 485 million years ago, shell percentages rose. This increase lines up with the Cambrian Explosion, a period when life rapidly diversified.



Early on, sponges were major players. Later, they were overtaken by echinoderms (ancestors of starfish) and arthropods like trilobites. 



<h2 class="wp-block-heading" id="h-a-gradual-increase-in-biomass">A gradual increase in biomass </h2>



Over the next 230 million years, shell content stayed mostly above 20 percent, aside from big dips during <a href="https://www.earth.com/news/marine-life-became-strangely-uniform-after-earths-worst-mass-extinction/">mass extinctions</a>.



One of the sharpest declines came during the Permian-Triassic extinction about 250 million years ago - the “Great Dying.” Shell material dropped to just 3 percent. 



Life rebounded after that, although smaller setbacks followed during the end-Triassic and the well-known Cretaceous-Paleogene extinction 66 million years ago.



In our current era - the Cenozoic - shell volume climbed above 40 percent, boosted by creatures like mollusks and corals. “The overall pattern that we were able to capture is that it’s a gradual increase,” Singh said.



<h2 class="wp-block-heading" id="h-consistent-biological-patterns">Consistent biological patterns </h2>



The team knew they had to rule out alternative explanations. Maybe shell-boring predators were less common in the past. Maybe certain environments were overrepresented in the data. 



To check, the researchers sorted samples by depth, latitude, and geological setting. The trend held steady.



“The more tests we did and the more we divided our dataset, we realized that these big biological patterns we were seeing stayed over time,” Singh said.



<h2 class="wp-block-heading" id="h-why-did-ocean-life-keep-growing">Why did ocean life keep growing?</h2>



The answer may come down to diversity. As life evolved to fill more ecological roles, it got better at using available energy. Organisms became more specialized, more interconnected. 



That allowed ecosystems to recycle nutrients more efficiently - from sunlight-eating phytoplankton to decomposers returning nutrients to the cycle.



“The overall idea is that there is more food available in ecosystems and because of that, the ecosystems can support more life, there’s more energy available, and that leads to greater abundance expressed in biomass,” Singh said.



<h2 class="wp-block-heading" id="h-humans-are-rapidly-changing-ocean-life">Humans are rapidly changing ocean life</h2>



The study paints a long view of life’s upward climb, but it ends before the modern age. Today’s oceans face threats from overfishing, pollution, acidification, and climate change. 



Researchers agree - we’re already in the middle of a human-caused sixth mass extinction. And if biodiversity keeps falling, we may see long-term drops in biomass too - with effects that could last millions of years.



“From our study’s perspective, modern times are quite complicated given the extent of human activity that’s rapidly altering conditions planetwide, including in the oceans,” said Payne. 



“But our findings show that overall biomass is linked to biodiversity and that losses in biodiversity may suppress productivity for geologically meaningful intervals, adding one more argument of why conserving biodiversity is essential for the health of humans and our planet.”



The full study was published in the journal <a href="https://linkinghub.elsevier.com/retrieve/pii/S0960982225007353">Current Biology</a>.



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Fossils reveal 500 million years of changes in ocean life

We know the oceans are changing. But how have they...

For 50 years, scientists believed that fish schools saved energy by swimming in diamond formations. This view, rooted in models by Weihs and Lighthill from the 1970s, shaped decades of research and robotic design. 



However, new research from <a href="https://www.princeton.edu" target="_blank" rel="noreferrer noopener">Princeton</a> and <a href="https://www.harvard.edu" target="_blank" rel="noreferrer noopener">Harvard</a> scientists turns that theory on its head. <a href="https://www.earth.com/news/small-fish-species-are-the-big-catch-of-the-future/">Fish</a> don't move in neat, flat diamonds. Instead, they prefer dynamic, three-dimensional ladders.



<h2 class="wp-block-heading" id="h-a-new-look-at-fish-schooling-patterns">A new look at fish schooling patterns</h2>



The researchers tracked six giant danios swimming continuously for ten hours in a recirculating flow tank. They used synchronized side and bottom cameras, along with deep learning software, to collect detailed 3D data on fish positions. 



This advanced setup allowed the team to record over 260,000 frames where at least four fish were clearly visible and trackable from both views.



The findings challenged long-held assumptions about fish schooling patterns. Only 0.1% of the frames showed fish in the classical diamond formation, long thought to be the most energy efficient. 



<h2 class="wp-block-heading" id="h-fish-mostly-swim-in-ladders">Fish mostly swim in ladders</h2>



Instead, the fish predominantly adopted a new three-dimensional arrangement termed the ladder formation. In this pattern, <a href="https://www.earth.com/news/small-fish-provide-climate-resilient-nutrition-for-a-warming-world/">fish</a> were staggered vertically, with some swimming slightly above or below others, rather than maintaining a flat side-by-side structure.



The ladder pattern appeared in 79% of fish pairings, making it by far the most common. Additionally, only 25.2% of all fish pairs swam in the same horizontal plane. This indicates that vertical positioning is a key feature of natural fish school behavior, something that earlier two-dimensional studies overlooked. 



The study reveals that fish prefer dynamic 3D arrangements that likely reduce drag without requiring precise alignment.



<h2 class="wp-block-heading" id="h-why-the-fish-ladder-works">Why the fish ladder works</h2>



“When swimming, <a href="https://www.earth.com/news/how-alternative-seafood-can-help-save-our-oceans/">fish</a> on average generate a jet going backward, like the jet engine of a plane,” said Hungtang Ko, lead author of the study. Staying out of that jet reduces drag.



The ladder formation allows this. A fish swims slightly above or below the one in front, avoiding the jet while still staying close. This creates energy savings similar to the diamond model but with less need for perfect timing or alignment.



The diamond model assumes fish must synchronize tail beats and stay level. But in real schools, coordination varies. Fish rarely beat tails in exact anti-phase, a condition the diamond pattern needs to be effective.



Even in controlled experiments, <a href="https://www.earth.com/news/fish-are-quietly-battling-climate-change-on-the-seabed/">fish</a> constantly rearranged positions. The average pattern changed every 48 seconds for individuals and 32 seconds for the whole school.



Ko’s team observed that fish ladder formations shift based on flow rate. As speed increased from 1.6 to 5.6 body-lengths per second, the fish ladder stretched longer. This adaptation resembled behavior in other biological collectives, like fire ant rafts.



<h2 class="wp-block-heading" id="h-tracking-fish-in-three-dimensions">Tracking fish in three dimensions</h2>



Older studies limited fish to shallow tanks or still water, forcing unnatural formations. This experiment used deeper tanks and steady flow, removing boundary effects. 



The researchers trained AI to detect nose and tail positions in 3D space using SLEAP.ai and a custom MATLAB pipeline.



According to the heatmaps, fish were most likely to swim either above and behind, or below and ahead, of a partner - never directly inline.



This ladder structure formed naturally, not by training or conditioning. It shows how real-world conditions reshape what we think of as “efficient.”



<h2 class="wp-block-heading" id="h-why-this-matters-beyond-biology">Why this matters beyond biology</h2>



The Nagpal lab is designing robot fish swarms inspired by these new insights. By mimicking ladder formations, underwater robots might conserve energy, move more smoothly, and navigate better in tasks like reef monitoring.



“The collaboration is a two-way street,” said Ko. “We can use computer vision to discover how and why animal groups do things together. And then we can ask, what kind of real-world robotic system could this biological insight be applied to?”



<h2 class="wp-block-heading" id="h-fish-schools-conserve-energy">Fish schools conserve energy </h2>



This study shows that energy savings don’t come from holding a perfect formation. Instead, savings come from many temporary, varied arrangements. 



Even fish that constantly shift positions still gain benefits by staying out of each other's wake.



The study also raises new questions. Can robot fish switch positions while still conserving energy? Do vertical ladders work better in turbulent water? Future experiments, especially using robotic models, may find answers.



For now, one thing is certain. Nature prefers complexity over perfection. Fish don't swim in flat diamonds. They climb invisible ladders, one body length at a time.



The study is published in the journal <a href="https://www.nature.com/articles/s41598-025-06150-2" target="_blank" rel="noreferrer noopener">Scientific Reports</a>.



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Fish swim in schools by stacking like ladder rungs

For 50 years, scientists believed that fish schools saved energy...

Climate, geology, and biology together gave rise to one of Earth’s most dramatic turning points: the Cambrian explosion. About 530 million years ago, most of the basic body plans of organisms that have survived until now emerged.



Yet a new study argues that key elements of this revolutionary event actually took shape earlier - perhaps ten-plus million years before the formal start of the Cambrian Period.



The research relies not on bones or shells, but on trace fossils - the tracks, burrows, and other imprints left by organisms as they crawled through ancient sediments.



Co-authors Olmo Miguez Salas of the <a href="https://web.ub.edu/web/ub/">University of Barcelona</a> and Zekun Wang of London’s <a href="https://www.nhm.ac.uk/">Natural History Museum</a> analyzed these subtle signatures. 



The goal was to reconstruct early animal anatomy and behavior during the Ediacaran-Cambrian transition, roughly 545 million years ago.



<h2 class="wp-block-heading" id="h-fossil-traces-reveal-ancient-life">Fossil traces reveal ancient life</h2>



Traditional fossil studies skew toward creatures with hard parts, because bones and shells preserve most readily in rock. Trace fossils capture a different story: the activities of <a href="https://www.earth.com/news/earths-first-animals-were-very-picky-about-where-they-lived/">soft-bodied animals</a> that rarely leave skeletal remains.



“The trace fossil record provides valuable information about evolutionary periods when soft-bodied fauna were dominant,” Miguez Salas said.



“Fossil traces reflect the behavior of the organism that generates them, which is determined by habitat and responses to environmental stimuli. Therefore, they are an indicator of the palaeoecological conditions in which the organisms that generated them lived.”



That focus is especially useful for the Ediacaran-Cambrian boundary, a time when soft-bodied organisms still outnumbered shelly ones and ecological dynamics were in rapid flux.



Early burrowers and crawlers disturbed microbial mats on the seafloor. This paved the way for new feeding strategies, novel body plans, and ultimately the hard-part explosion more familiar to paleontologists.



<h2 class="wp-block-heading" id="h-fossils-show-how-life-moved">Fossils show how life moved</h2>



By quantifying the widths, lengths, and winding patterns of fossil trackways such as Archaeonassa, Gordia, Helminthopsis, and Parapsammichnites, the team derived scaling laws that link track size to the animals’ own proportions. 



The results show that organisms with streamlined, elongated profiles were already active 545 million years ago.



“These organisms probably possessed coelomic hydrostatic bodies, with an anteroposterior axis, muscles, and possibly segmentation,” Miguez Salas said.



“Furthermore, these organisms could move in a specific direction (directional <a href="https://www.earth.com/news/not-all-kangaroo-ancestors-hopped-as-a-means-of-locomotion/">locomotion</a>) and probably possessed sensory capabilities to move and feed on heterogeneous substrates in a habitat dominated by microbial mats.”



<h2 class="wp-block-heading" id="h-traits-predate-cambrian-explosion">Traits predate Cambrian explosion</h2>



Such abilities - directional crawling, muscular movement, possible segmentation - echo the hallmarks of bilaterian animals that dominate the modern biosphere. 



If those traits existed well before 530 million years ago, then the lineage-splitting events that scientists historically assign to the Cambrian must have roots in the late <a href="https://www.earth.com/news/591-million-years-ago-complex-life-emerged-on-earth-magnetic-field-ediacaran-period/">Ediacaran</a>.



“Therefore, the so-called Cambrian explosion and its evolutionary implications may have occurred much earlier than estimated,” Miguez Salas added.



Instead of a sudden burst, the data point toward a protracted interval of experimentation. Ecological engineering by active burrowers created niches that later organisms exploited.



<h2 class="wp-block-heading" id="h-math-reveals-ancient-mobility">Math reveals ancient mobility</h2>



Until now, suggestions of pre-Cambrian complexity leaned heavily on qualitative observations - isolated sites showing possible bilateral tracks or ambiguous body impressions. What sets the new paper apart is its mathematical approach.



The authors modeled modern track size to body length, then applied that scaling framework to ancient trace fossils. The outcome is a statistically grounded estimate of early animal width, length, and locomotion speed.



“This new discovery opens the door to quantitatively study future Ediacara trace fossils and to corroborate that the explosion did not happen in the Cambrian, but many millions of years earlier,” Miguez Salas said.



The same scaling rules could probe other critical transitions, such as the <a href="https://www.earth.com/news/tiny-worms-sparked-explosive-evolutionary-period-of-life-on-earth/">Great Ordovician Biodiversification Event</a>, offering a consistent yardstick for comparing evolutionary shifts across geologic time.



<h2 class="wp-block-heading" id="h-fossils-shift-life-s-timeline">Fossils shift life’s timeline</h2>



If complex bilaterians were shaping seafloor habitats 545 million years ago, paleontologists must rethink long-held assumptions. Environmental and genetic triggers like <a href="https://www.earth.com/news/rewrite-the-textbooks-life-on-earth-did-not-arise-due-to-increased-oxygen-levels/">oxygen</a> rise, ocean shifts, or gene changes may need rethinking for the Cambrian proper. 



Those factors may have been in motion earlier, with the visible “explosion” marking only the point when hard parts made diversity easier to preserve.



The study also underscores how behaviors - burrowing, mat-grazing, sediment mixing - can serve as evolutionary catalysts. Mobile animals turning over sediment could have unleashed nutrients, altered <a href="https://www.earth.com/news/microbes-laid-the-foundation-for-early-life-on-earth/">microbial communities</a>, and spurred arms races that drove further innovation.



<h2 class="wp-block-heading" id="h-what-fossils-may-still-reveal">What fossils may still reveal</h2>



Future expeditions into late Ediacaran strata may uncover additional trace fossil assemblages to test the new timeline. 



High-resolution 3D scans, geochemical proxies, and refined radiometric dating can link track-making horizons to precise ages and environmental conditions.



Meanwhile, the mathematical framework introduced by Miguez Salas and Wang equips researchers worldwide to translate faint surface scribbles into vivid portraits of Earth’s earliest movers and shakers.



In shifting the Cambrian explosion’s fuse back several million years, the fossil record reminds us that life’s history often blurs textbook boundaries. Evolution, like geology itself, tends to roll out gradually - until we gather the evidence to see its subtler steps.



The study is published in the journal <a href="https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G53332.1/655874/Quantitative-decoding-of-Ediacaran-locomotory">Geology</a>.



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Cambrian explosion: Fossils push back the rise of complex life

Climate, geology, and biology together gave rise to one of...

We used to think leopard seals had broad diets, but new research suggests that many individuals are picky eaters - with big consequences.



While the species as a whole eats many prey types, <a href="https://www.earth.com/news/harbor-seals-rely-on-visual-cues-to-navigate-cloudy-waters/">individual</a> seals often specialize. This pattern has ecosystem-wide effects, especially in the predator-rich waters off Cape Shirreff.



<h2 class="wp-block-heading" id="h-leopard-seals-prefer-specific-diets">Leopard seals prefer specific diets</h2>



The research team analyzed stable isotope values (δ15N and δ13C) from 46 whiskers of 34 seals. This long-term data covered a decade. 



The results showed that 59% of the seals were dietary specialists, 28% were intermediates, and only 13% were true generalists.



Specialists fall into two categories. High trophic level specialists likely hunt fur <a href="https://www.earth.com/news/seal-pregnancies-reveal-clues-for-treating-birth-complications/">seal</a> pups and large fish. Medium to low trophic level specialists target krill, penguins, and cephalopods. 



The research suggests that individual differences in diet shape local food webs more than previously assumed.



“Even though leopard seals as a species eat a wide variety of prey, most individuals actually focus on just a few types of food,” said study co-author Dr. Emily Sperou from <a href="https://www.baylor.edu" target="_blank" rel="noreferrer noopener">Baylor University</a>. 



“This means that a few highly specialized seals can have a much bigger effect on certain prey populations than we previously thought.”



<h2 class="wp-block-heading" id="h-some-seal-diets-don-t-change">Some seal diets don’t change</h2>



The study revealed two long-term foraging styles. Some individuals, like seal 397, maintained high trophic level specialization for up to ten years. 



Others, like seal 12, changed diets significantly across five years, from specialist to generalist.



This variability suggests behavioral flexibility. <a href="https://www.earth.com/news/elephant-seals-provide-a-window-into-the-oceans-twilight-zone/">Seals</a> might shift strategies depending on prey availability or competition. Such changes could buffer the species against ecosystem shifts.



“A few specialists can help shape entire ecosystems,” said study co-author Dr. Patrick Charapata. 



“Understanding these patterns in leopard seals and other top predators can help us better predict and manage changes to prey populations and the greater ecosystem these species live in.”



<h2 class="wp-block-heading" id="h-leopard-seal-diets-and-prey-populations">Leopard seal diets and prey populations </h2>



Larger female leopard seals were found to consistently feed at higher trophic levels compared to males. This means they targeted prey that are themselves predators or occupy higher positions in the food web. 



Interestingly, all the individuals identified as high-level dietary specialists in the study were female. Their greater body size likely plays a key role in this pattern. 



Bigger <a href="https://www.earth.com/news/weddell-seals-have-a-surprising-survival-strategy/">seals</a> are physically capable of capturing and consuming larger, more energy-dense prey, such as Antarctic fur seal pups. This access to richer food sources gives them an energetic advantage and increases their impact on prey populations.



<h2 class="wp-block-heading" id="h-individuals-with-a-large-impact">Individuals with a large impact</h2>



The data also showed that females had broader isotopic ranges in their whisker samples. This suggests they influence a wider range of the ecosystem through their feeding habits. They do not just eat more; they affect more parts of the food web.



A few large females were found to be responsible for most of the observed predation on fur seal pups. One individual, identified as seal 397, stood out in particular. She had the highest number of recorded pup captures in the study. 



Her method involved ambush style attacks, showing strategic hunting behavior that likely made her even more effective. This highlights how a small number of powerful individuals can have an outsized effect on an ecosystem.



<h2 class="wp-block-heading" id="h-diets-change-with-prey-numbers">Diets change with prey numbers</h2>



The data revealed a sharp drop in δ15N values between 2015 and 2017. This trend aligns with a known decline in Antarctic fur seals and some penguin species. Researchers believe the drop reflects a reduction in nitrogen-rich prey.



From 2017 to 2023, the number of leopard seals at Cape Shirreff fell by 76 percent. The few that remained, like seal 397, regained access to higher trophic prey. As competition dropped, δ15N values began rising again.



The study reshapes how we think about predator roles. Individual specialization can reshape ecosystems. Just a few high-impact predators may shift prey dynamics dramatically.



For instance, a pod of five orcas once consumed 8,500 sea otters annually. Leopard seals may be exerting similar pressure on fur seal colonies.



Current conservation strategies often assume that all individuals in a species behave alike. But this study warns against such assumptions. Ignoring individual-level behavior might cause poor management decisions, especially under climate stress.



<h2 class="wp-block-heading" id="h-leopard-seals-and-prey-dynamics">Leopard seals and prey dynamics</h2>



The study relied on stable isotope data but did not include direct prey identification. Future research could pair isotopic signatures with tracking and observational data.



While this study was focused on Cape Shirreff, genetic data indicate that these findings may apply to leopard seals across the Southern Ocean.



The research shows how a few individual predators can shape the fates of entire species. Leopard seals remind us that even in the coldest oceans, personal dietary choices matter.



The study is published in the journal <a href="https://onlinelibrary.wiley.com/doi/10.1002/ece3.71593" target="_blank" rel="noreferrer noopener">Ecology and Evolution</a>.



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Leopard seal diets are reshaping Antarctic ecosystems

We used to think leopard seals had broad diets, but...

Once thought unique to humans, grief may exist in other species too. New research from Osaka University shows that Japanese macaques react to dying and dead group members with surprising emotion.



Published in the journal Primates, the study reveals responses beyond mothers mourning infants. It focuses instead on how macaques behave around dying or deceased adult <a href="https://www.earth.com/news/assamese-macaques-show-how-aging-affects-our-social-networks/">companions</a>.



<h2 class="wp-block-heading" id="h-macaques-stay-near-dying-friends-nbsp">Macaques stay near dying friends&nbsp;</h2>



Japanese macaques live in complex societies and form long-term grooming partnerships. Researchers tracked grooming and proximity over several years to explore whether social <a href="https://www.earth.com/news/social-tolerance-helps-monkeys-pass-along-new-skills/">closeness</a> influenced their behavior during death-related events.



“It’s incredibly rare to document these kinds of behaviors in wild animals,” said lead author Masayuki Nakamichi from <a href="https://www.osaka-u.ac.jp/en" target="_blank" rel="noreferrer noopener">Osaka University</a>. 



Macaques with strong grooming histories often stayed close to the deceased. Others kept their distance, especially when they had no prior bond.



<h2 class="wp-block-heading" id="h-visible-decay-alters-behavior">Visible decay alters behavior</h2>



Maggots played a central role in group reactions. In three of the four documented deaths, the bodies showed infestation. This strongly affected how others responded.



Monkeys typically avoided touching or approaching maggot-covered individuals. Some jumped away after sniffing the wound. Others looked and then left quickly.



Yet in one exceptional case, the group’s alpha female, Pet, groomed a dying male named Rikinio even as flies swarmed around him. She picked maggots from his back and ate them.



“The fact that some individuals remained near deceased <a href="https://www.earth.com/news/sulawesi-macaques-face-unknown-threats-from-plastic-waste/">companions</a> they had close relationships with suggests that these macaques have emotional capacities that resemble human compassion,” said study co-author Kazunori Yamada.



This behavior suggests macaques can form deep attachments and remain emotionally affected by death.



<h2 class="wp-block-heading" id="h-macaques-react-to-different-deaths">Macaques react to different deaths</h2>



Case 1 featured Rikinio, a high-ranking male wounded by a rival. Most macaques avoided him once his wound became infested. Pet alone groomed him and consumed maggots during the process.



Case 2 followed another male, K75, who declined from old age. Though his body showed no visible wounds, flies and rain had changed his appearance. Familiar group members hesitated to come near, possibly recalling his earlier condition.



Case 3 involved Pet79, a female from the dominant kin group. After returning from a long absence, she was groomed by her daughters. A month later, with maggots visible in her wounds, even close family avoided her.



Case 4 described Pet87, who died in winter. His body had no maggots. Group members remained close. A juvenile female groomed his corpse. Her mother had groomed Pet87 regularly when he was alive.



<h2 class="wp-block-heading" id="h-disease-avoidance-may-play-a-role">Disease avoidance may play a role</h2>



Macaques appear to avoid corpses showing signs of infestation. This may be a survival behavior. Avoiding flies and maggots likely reduces the risk of disease.



Many reacted by sniffing their fingers after contact or rubbing them on the ground. These actions suggest discomfort triggered by smell or touch.



When the corpse showed no damage or signs of infestation, macaques behaved calmly and remained nearby. This pattern supports the idea that visible decay, more than death itself, shapes avoidance.



<h2 class="wp-block-heading" id="h-death-awareness-in-macaques">Death awareness in macaques</h2>



Some behaviors hint at cognitive recognition of death. One low-ranking male, who avoided a higher-ranking male while alive, stayed near his corpse. Possibly, he understood the male no longer posed a threat.



Other group members hesitated to enter areas where a corpse lay still. This unusual caution may reflect recognition that something was not normal.



These findings suggest that macaques feel <a href="https://www.earth.com/news/hurricane-on-monkey-island-made-macaques-more-socially-tolerant/">emotions</a> like grief and compassion, at least in simple forms. The depth of their understanding remains unclear, but their actions show social bonds do not always end with death.



“More observations of death-related events in more species will be needed to fully understand the emotional responses of non-human primates to the dead,” said Nakamichi.



<h2 class="wp-block-heading" id="h-path-forward-in-primate-thanatology">Path forward in primate thanatology</h2>



To learn more, the researchers want to combine behavioral studies with physiological data. Measuring hormone levels, tracking stress responses, and observing reactions to smell may offer deeper insights.



Chimpanzees, for example, show aversion to the scent of putrescine, a chemical linked to decay. Similar tests in macaques may reveal if scent triggers their aversion or if vision plays a bigger role.



This study challenges long-held beliefs about grief. Japanese macaques show emotion toward the dying and dead, guided by bonds and sensory cues.



They remind us that even in the forest, empathy may bloom. Loss does not go unnoticed.



The study is published in the journal <a href="https://link.springer.com/article/10.1007/s10329-025-01196-2" target="_blank" rel="noreferrer noopener">Primates</a>.



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Japanese macaques have social bonds that persist beyond death

Once thought unique to humans, grief may exist in other...

Squid are famous for flashing from glass-clear to kaleidoscopic in the blink of an eye, but biologists have long puzzled over the physical trick behind the act.



A research team led by the <a href="https://www.uci.edu/">University of California, Irvine</a>, joined by cephalopod experts at the <a href="https://www.mbl.edu/">Marine Biological Laboratory</a> in Woods Hole, took that mystery head-on.



By peering into squid skin in three dimensions, they uncovered a hidden forest of nano-columns built from an uncommon protein called reflectin.



<h2 class="wp-block-heading" id="h-how-squid-skin-bends-light">How squid skin bends light</h2>



These columns act much like tiny mirrors, bouncing or passing light depending on how close together they sit.



Alon Gorodetsky, an expert in chemical and biomolecular engineering at UC Irvine, is the senior author of the research.



“In nature, many animals use Bragg reflectors [which selectively transmit and reflect light at specific wavelengths] for structural coloration,” he said. “A squid’s ability to rapidly and reversibly transition from transparent to colored is remarkable."



"We found that cells containing specialized subcellular columnar structures with sinusoidal refractive index distributions enable the squid to achieve such feats.”



<h2 class="wp-block-heading" id="h-studying-the-master-shapeshifter">Studying the master shapeshifter</h2>



The animals under study were longfin inshore squid, Doryteuthis pealeii. “These are longfin inshore squids – Doryteuthis pealeii – that are native to the Atlantic Ocean,” Gorodetsky said.



“Marine Biological Laboratory has been famous for studying this squid and other cephalopods for more than a century. We were fortunate to be able to leverage their world-class expertise with properly collecting, handling, and studying these biological specimens.”



Inside the squid mantle, shimmering cells known as iridophores - or iridocytes - hold the secret. 



To visualize them without disturbing their delicate innards, the team used holotomography, a form of quantitative phase microscopy that maps how <a href="https://www.earth.com/news/physicists-succeed-in-converting-light-into-a-supersolid-that-flows-like-a-liquid/">light</a> bends through a sample.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/06/squid-skin_color-change_montage_credit-UCIrvine_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/06/squid-skin_color-change_montage_credit-UCIrvine_1s.webp" alt="Digital camera images of the entire body (top left) and dorsal mantle (top right) of a squid show the splotches' blue, green, yellow, orange and red iridescent (angle-dependent) colors. An individual splotch (bottom, from left) transitions from transparent to red to orange to green at 0, 60, 90 and 120 seconds, respectively, when subjected to chemical and neurophysiological stimuli. Credit: Alon Gorodetsky Lab, UC Irvine" class="wp-image-1975656"/></a><figcaption class="wp-element-caption">Digital camera images of the entire body (top left) and dorsal mantle (top right) of a squid show the splotches' blue, green, yellow, orange and red iridescent (angle-dependent) colors. An individual splotch (bottom, from left) transitions from transparent to red to orange to green at 0, 60, 90 and 120 seconds, respectively, when subjected to chemical and neurophysiological stimuli. Click image to enlarge. Credit: Alon Gorodetsky Lab, UC Irvine</figcaption></figure>



Georgii Bogdanov, a postdoctoral researcher in chemical and biomolecular engineering at UC Irvine, is another lead author of the study.



“Holotomography used the high refractive index of reflectin proteins to reveal the presence of sinusoidal refractive index distributions within squid iridophore cells,” he said.



Reflectin platelets form spiral columns inside iridophores, enabling cephalopods to control how their skin transmits and reflects light.



<h2 class="wp-block-heading" id="h-borrowing-nature-s-blueprint"><a></a>Borrowing nature’s blueprint</h2>



Once the researchers understood the architecture - the stacked, spiraling Bragg reflectors - they wondered whether they could engineer something similar.



Studying squid color change inspired flexible materials that shift appearance using tiny, wavy Bragg reflector columns. They added nanostructured metal films, enabling the materials to also shift appearance in the infrared spectrum.



Using a mixture of polymer chemistry, nanofabrication, and metal coatings, the group built thin films that shift color when stretched, pressed, or heated. 



They went a step further by tailoring the same films to tune their <a href="https://www.earth.com/news/mosquitoes-use-thermal-infrared-vision-to-track-and-bite-humans/">infrared</a> emission. This allows the material to hide or reveal heat signatures as well as visible hues.



“These bioinspired materials go beyond simple static color control, as they can dynamically adjust both their appearances in the visible and infrared wavelengths in response to stimuli,” said co-author Aleksandra Strzelecka, a PhD student at UC Irvine.



“Part of what makes this technology truly exciting is its inherent scalability," she said. "We have demonstrated large-area and arrayed composites that mimic and even go beyond the squid’s natural optical capabilities."



This opens the door to many applications ranging from adaptive <a href="https://www.earth.com/news/how-squid-power-their-amazing-camouflage-abilities/">camouflage</a> to responsive fabrics to multispectral displays to advanced sensors.



<h2 class="wp-block-heading" id="h-future-optics-from-squid-skin">Future optics from squid skin</h2>



The implications stretch far beyond a novelty coating. The same Bragg-style stacks could sharpen laser output, filter signals in fiber-optic lines, and boost solar-cell efficiency. They could also enable real-time structural health monitoring in bridges and aircraft.



“This study is an exciting demonstration of the power of coupling basic and applied research,” Gorodetsky said. “We have likely just started to scratch the surface of what is possible for cephalopod-inspired tunable optical materials in our laboratory.”



Every advance stemmed from squid skin cells with tiny winding columns just hundreds of nanometers wide. Despite their size, these structures could orchestrate a light show visible from meters away.



The team’s work shows how decoding those natural nanostructures can lead to devices that humans manufacture by the meter rather than by the molecule.



<h2 class="wp-block-heading" id="h-squid-inspired-tech-evolves">Squid-inspired tech evolves</h2>



Researchers aim to speed up film response and develop biodegradable versions for sensors and medical patches.



Meanwhile, the discovery reaffirms why <a href="https://www.earth.com/news/octopus-and-squid-senses-linked-to-human-brain-evolution/">cephalopods</a> remain a favorite subject for materials scientists: they are masters of manipulating light without a single pigment or battery.



In the lab, that mastery is starting to take shape as fabrics that cool soldiers in the desert by day, buildings that shimmer to reduce air-conditioning loads, and flexible screens that display both artwork and thermal data.



The next chapter, as Gorodetsky’s group sees it, will be written where biology and engineering merge. 



The squid’s split-second shape-shifting trick has journeyed from the Atlantic deep to a microscope slide and into a polymer film. 



Soon, it may appear on your jacket sleeve or smartphone case, blending vivid color with invisible infrared control just like in cephalopods.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adn1570" target="_blank" rel="noreferrer noopener">Science</a>.



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Scientists unlock the light-bending secrets of squid skin

Squid are famous for flashing from glass-clear to kaleidoscopic in...

Anyone who has ever tossed and turned at night knows how much sleep matters. Stress, social distractions, and even the weather can disrupt our rest. And it turns out we’re not the only ones.



Orangutans - some of our closest living relatives - face similar challenges, and they’ve figured out a relatable solution: they nap.



<h2 class="wp-block-heading" id="h-tired-minds-and-busy-days">Tired minds and busy days</h2>



Life in the rainforest is no easy task for <a href="https://www.earth.com/news/orangutans-use-complex-vocal-patterns-found-in-human-language/">orangutans</a>. Every day involves travel, food gathering, social puzzles, and constant movement - mental and physical strain is inevitable.



“Moving through the canopy, finding food, solving problems, navigating social relationships; these are all tiring and cognitively demanding tasks,” said&nbsp;Alison Ashbury, the study’s first author. 



“When an orangutan doesn’t get enough sleep, it does what any sleep-deprived human might do: it climbs into bed, lies down, and takes a nap.”



Scientists from the <a href="https://www.ab.mpg.de/">Max Planck Institute of Animal Behavior</a> (MPI-AB) and the University of Konstanz in Germany, together with collaborators at the Universitas Nasional in Indonesia, studied wild orangutans in the rainforests of Sumatra. 



The goal was to understand how these great apes manage their sleep in the wild and what that can teach us about the evolution of rest in <a href="https://www.earth.com/news/bonobos-group-cohesion-common-enemy-effect-do-not-kill-inside-their-species/">primates</a>.



<h2 class="wp-block-heading" id="h-monitoring-orangutan-bedtimes">Monitoring orangutan bedtimes</h2>



For over 14 years, the team collected behavioral data on 53 adult orangutans at the Suaq Balimbing Monitoring Station. They followed the animals through 455 days and nights, closely watching how and where they slept.



Each evening, adult orangutans build a sleeping “nest” high in the treetops. This nest acts as a bed, with branches woven together to form a secure platform. 



The orangutans even add leaves for a mattress and pillow. Mothers share nests with their nursing babies, but otherwise, adults sleep solo. At dawn, they leave the nest and begin the day.



“From our point of view on the ground, we usually can’t see orangutans at all in their night nests, but we can hear them rustling around, getting comfortable,” said Caroline Schuppli, the study’s senior author and a group leader at MPI-AB. “Eventually, everything goes quiet and still. And the reverse happens in the morning.”



The researchers measured the period of nighttime silence as a proxy for sleep. Although they couldn’t directly monitor brain activity, the length of this quiet period closely matched patterns of actual sleep observed in captive orangutans and wild <a href="https://www.earth.com/news/baboons-walk-in-lines-just-to-stay-near-their-friends/">baboons</a>. On average, orangutans slept for nearly 13 hours each night.



<h2 class="wp-block-heading" id="h-what-interrupts-orangutan-sleep">What interrupts orangutan sleep?</h2>



Several factors disrupted sleep. Orangutans had shorter sleep periods when they built their nests close to others and when nights were colder. Sleep was also reduced on days when they had traveled farther.



“We thought it was really interesting that just being near other orangutans when building a night nest was linked to shorter sleep periods,” said Ashbury. “Imagine you stay up late hanging out with your friends, or your roommate is snoring so loudly in the morning that you get up early. I think it’s a bit like that."



"They’re prioritizing being social over sleeping, or their sleep is being disrupted by others nearby, or even both.”



<h2 class="wp-block-heading" id="h-naps-after-sleepless-nights">Naps after sleepless nights</h2>



The team also explored how orangutans compensate for lost sleep. They found a consistent pattern: when orangutans had shorter nighttime sleep, they napped more during the day. In fact, for every hour less sleep the night before, they added 5 to 10 extra minutes of nap time the next day.



“For people, even a short nap can have significant restorative effects,” noted the researchers. “It’s possible that these naps are helping orangutans reset physiologically and cognitively after a poor night’s sleep, just like they do in humans.”



The orangutans used simple, quickly built day nests for these <a href="https://www.earth.com/news/how-do-afternoon-naps-impact-our-health/">naps</a>. These nests took less than two minutes to construct, lacked many of the comfort features of night nests, and were used solely for short rest periods.



“Day nests are less sophisticated, have fewer comfort elements, and are made quicker than night nests,” said Schuppli. “But even so, when we’re able to see an orangutan resting in a day nest, we see that their bodies are relaxed and their eyes are closed. They really do appear to be sleeping.”



<h2 class="wp-block-heading" id="h-naps-and-brain-power">Naps and brain power</h2>



Scientists have long recognized the Suaq orangutans for their exceptional mental abilities. Their frequent napping habits may play a role in supporting this cognitive edge.



“Among all studied orangutan populations, the Suaq orangutans arguably exhibit the widest range of cognitively demanding behaviors,” said Schuppli, who also directs research at the site. 



“This may be linked to their relatively high propensity for daytime nest use. Either they need these high-quality naps to meet their cognitive demands, or their cognitive abilities can come about because they take high-quality naps in day nests so often.”



Another possible factor is their semi-solitary lifestyle. Orangutans don’t live in tight social groups, so they’re free to nap when they feel the need. 



The data showed that orangutans took at least one nap on 41% of observed days, and those naps averaged 76 minutes.



<h2 class="wp-block-heading" id="h-lessons-from-wild-sleep">Lessons from wild sleep</h2>



“Studying sleep in the wild, in the natural social and ecological conditions under which it evolved, is important to broadening our understanding of the evolutionary origins and the ultimate functions of sleep,” said Meg Crofoot, director at MPI-AB and a professor at the University of Konstanz. 



“Why did animals, from humans to primates to spiders to jellyfish, evolve to spend such large portions of their lives in this vulnerable unconscious state? If we’re going to answer this question, we need to bring sleep research out of the lab and into the field. Studies such as this one contribute to that effort.”



Orangutans napping in leafy nests may seem like a simple sight. But their resting habits may hold deeper clues about sleep’s role in intelligence, social life, and <a href="https://www.earth.com/news/survival-of-the-fittest-study-suggests-its-more-a-game-of-chance/">survival</a> - for them and for us.



The full study was published in the journal <a href="https://linkinghub.elsevier.com/retrieve/pii/S0960982225006694">Current Biology</a>.



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Orangutans manage sleep much like humans do

Anyone who has ever tossed and turned at night knows...

Cod once ruled the Baltic Sea - massive, plentiful, and essential to the region’s fishing economy. They often stretched over a meter long and weighed up to 40 kilograms. 



Along with herring, cod once sustained industries, communities, and families. Now, they have vanished - at least in their original form. 



Catching an impressive-sized cod is a rare sight - and is no longer permitted. A ban on targeted cod fishing has been in effect since 2019, following a population collapse.



It’s not just the numbers that plummeted. Cod shrank, and the changes didn't stop at the surface level. 



<h2 class="wp-block-heading" id="h-fishing-pressure-rewired-a-species">Fishing pressure rewired a species</h2>



According to researchers from <a href="https://www.geomar.de/en/">GEOMAR Helmholtz Centre for Ocean Research Kiel</a>, decades of intense fishing pressure didn’t just reduce the population - it rewired the species itself. 



The new study shows that human actions have altered the actual genetic makeup of cod in the Baltic Sea.



“Selective overexploitation has altered the genome of Eastern Baltic cod,” explains Dr. Kwi Young Han, the study’s first author. “We see this in the significant decline in average size, which we could link to reduced growth rates." 



"For the first time in a fully marine species, we have provided evidence of evolutionary changes in the genomes of a <a href="https://www.earth.com/news/oceans-are-quickly-losing-ability-to-support-fish-due-to-plankton-loss/">fish population</a> subjected to intense exploitation, which has pushed the population to the brink of collapse.”



<h2 class="wp-block-heading" id="h-changes-in-cod-genetics">Changes in cod genetics</h2>



The study links specific genetic changes to a shift in how cod grow and reproduce. The researchers found that genetic variants tied to growth became more or less common over time - classic signs of what’s called directional selection. 



These variants weren’t random either. They matched up with known genes that influence size and reproduction.



The experts also observed changes in a particular section of the cod genome - a chromosomal inversion - that typically helps animals adapt to environmental stress. 



In this case, it followed the same <a href="https://www.earth.com/news/lifes-rules-natural-selection-change-significantly-often-daphnia/">selection</a> pattern, reinforcing that the shrinking of the cod isn’t just bad luck or poor diet. It’s evolution, triggered by how we fish.



<h2 class="wp-block-heading" id="h-dna-from-the-past">DNA from the past</h2>



To study this long-term shift, the team turned to something unusual: tiny stones in fish ears called otoliths. Like tree rings, they store growth data year by year. 



The scientists used 152 otolith samples collected from the Bornholm Basin between 1996 and 2019 - part of GEOMAR’s Baltic Sea Integrative Long-Term Data Series.



The researchers paired chemical analysis of the otoliths with high-resolution DNA sequencing. They traced how cod growth patterns and genetic traits shifted across nearly three decades of <a href="https://www.earth.com/news/the-hidden-consequences-of-catch-and-release-sport-fishing/">fishing pressure</a>.



<h2 class="wp-block-heading" id="h-evolution-driven-by-human-activity">Evolution driven by human activity</h2>



The outcome? Cod that grew fast and large used to be common. Now, they’ve nearly vanished. The survivors are the ones that grow slower, mature smaller, and escape early capture.



“When the largest individuals are consistently removed from the population over many years, smaller, faster-maturing fish gain an evolutionary advantage,” noted Dr. Thorsten Reusch, head of the Marine Ecology Research Division at GEOMAR. 



“What we are observing is <a href="https://www.earth.com/news/fish-evolution-takes-place-in-decades-not-millions-of-years/">evolution</a> in action, driven by human activity. This is scientifically fascinating, but ecologically deeply concerning.”



<h2 class="wp-block-heading" id="h-cod-recovery-isn-t-guaranteed">Cod recovery isn’t guaranteed</h2>



The genetic changes found in cod aren't easily reversible. Cod that grow slowly and reproduce early might be surviving, but they’re also less productive. They mature at smaller sizes and produce fewer offspring. 



Furthermore, the genetic diversity of cod is shrinking. This diversity is crucial for helping species adapt to new conditions.



“Evolutionary change unfolds over many generations,” said Dr. Reusch. “Recovery takes far longer than decline, and it may not even be possible. This is evident in our 2025 length data from the current ALKOR cruise: despite the fishing ban, there’s no sign of a rebound in body size.”



<h2 class="wp-block-heading" id="h-significance-of-cod-genetics">Significance of cod genetics</h2>



This isn’t just about fish. It’s about how quickly humans can push a species to evolve in real time - and how hard it is to undo that. Genetic changes don’t bounce back when the pressure’s off. They linger, and in many cases, they stick.



“Our results demonstrate the profound impact of human activities on wild populations, even at the level of their DNA,” said Dr. Han. “They also highlight that sustainable <a href="https://www.earth.com/news/bleaching-effect-coral-loss-threatens-fisheries-and-livelihoods/">fisheries</a> are not only an economic issue, but also a matter of conserving biodiversity, including genetic resources.”



The science is clear. Overfishing doesn’t just take fish out of the sea. It leaves a permanent mark on the species. And it might have already cost us more than we can get back.



The full study was published in the journal Science Advances.



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Humans have changed the genetic makeup of cod

Cod once ruled the Baltic Sea - massive, plentiful, and...

Plateosaurus,Couple,,Dinosaurs,From,The,Late,Triassic,Period,Walking,On

Every visitor to the Natural History Museum in Zurich is greeted by a massive dinosaur skeleton nicknamed “Teoplati.” At first glance, it looks like any other prehistoric fossil on display, except for the presence of a serious bone infection. 



Teoplati’s story is anything but ordinary. 



This eight-meter Plateosaurus, which lived 220 million years ago in what is now Switzerland, met its end in sticky mud - and researchers say it was already struggling long before that. The dinosaur’s right arm, it turns out, was badly infected.



Scientists from the <a href="https://www.uzh.ch/en.html" target="_blank" rel="noreferrer noopener">University of Zurich</a>, along with researchers at the Frick Dinosaur Museum, recently studied the fossil and uncovered one of the oldest - and most severe - cases of bone infection ever recorded in a dinosaur.



<h2 class="wp-block-heading" id="h-mud-bound-dinosaur-had-a-useless-arm">Mud-bound dinosaur had a useless arm</h2>



Back in the <a href="https://www.earth.com/news/africas-oldest-known-dinosaur-recently-discovered/">Late Triassic </a>epoch, the Frick Valley in Aargau was a flat, dry landscape prone to sudden flooding. 



Picture a massive clay pit in a semi-arid basin - perfect for trapping large animals like Plateosaurus. Many of these dinosaurs likely died the same way: caught in the mud with no way out.



But this particular <a href="https://www.earth.com/news/scientists-discover-a-33-foot-jurassic-giant-twice-as-big-as-its-cousin-xingxiulong/">Plateosaurus</a> had even worse odds. It was already injured.



The dinosaur’s right shoulder and upper arm were severely damaged by a chronic infection. 



When researchers examined the bones, they found signs of intense inflammation and deformation - evidence that the animal’s limb had been unusable long before it became stuck in the mud.



<h2 class="wp-block-heading" id="h-ct-scanners-detect-dinosaur-bone-infection">CT scanners detect dinosaur bone infection</h2>



The nearly complete skeleton was unearthed in 2018. Paleontologists from the University of Zurich began studying it closely, especially the damaged limb. 



To get a better look inside, they used high-tech CT scanners at Empa, the Swiss Federal Laboratories for Materials Science and Technology.



These scanners, typically used for industrial research, were the only machines large enough to handle the dinosaur’s massive bones.



What they found was striking. The Plateosaurus likely suffered from <a href="https://www.earth.com/news/bone-disease-killed-off-australias-giant-thunder-birds/">osteomyelitis</a> - a serious infection that attacks bone tissue.



<h2 class="wp-block-heading" id="h-osteomyelitis-is-still-common-today">Osteomyelitis is still common today</h2>



"Osteomyelitis affects many living animals, including <a href="https://www.earth.com/news/evolutionary-mystery-why-are-mammals-the-only-vertebrates-to-have-only-one-lower-jawbone/">mammals</a> such as humans, as well as birds and reptiles," explained Jordan Bestwick, postdoctoral fellow at the Department of Paleontology at UZH.



"This disease is known to have affected several different dinosaur groups, including <a href="https://www.earth.com/news/giant-sauropods-walked-more-like-hippos-than-elephants/">sauropods</a>, so we had access to a range of specimens to compare our Plateosaurus with." said Bestwick.



"The affected bones in the shoulder and upper arm have unusually rough internal and external textures, altered shapes, and are even fused together - symptoms that are broadly typical of osteomyelitis."



What makes this case so unique is the size of the infected area. 



"Previous studies of osteomyelitis in dinosaurs report localized areas of infection, such as toe bones or a couple of adjacent bones in the spine," explained Bestwick.



"Having an entire infected shoulder and upper arm is very unusual. Although we don't know what initially caused the infection, the animal likely suffered from this disease for a substantial part of its life, possibly rendering its right arm useless."



<h2 class="wp-block-heading" id="h-jurassic-infection-links-dinosaurs-and-humans">Jurassic infection links dinosaurs and humans</h2>



Today, Teoplati stands tall at the entrance of the Natural History Museum at the University of Zurich. 



The skeleton lies in the exact position in which it was found. Next to it stands a life-sized reconstruction that shows what the animal may have looked like in life - including the deformed right arm.



Dennis Hansen, who led the exhibit’s creation at the museum, said the display tells more than just a biological story - it’s a personal one. "We wanted a display that highlights the tragic story of this particular animal," said Hansen.



The exhibit includes a diorama of cracked mud and footprints - some of the dinosaur’s last steps - before it sank beneath the surface.



"Together with the paleo-reconstruction wizards from the Danish company 10 Tons, we created a reconstruction based on the skeleton that also showcases the disease on its right arm and shoulder," said Hansen.



"This makes the display one of the few, worldwide, where the reconstruction of an individual dinosaur includes its pathologies."



In other words, it’s not just a dinosaur. It’s a story of injury, survival, and an unlucky end. Visitors walking into the museum aren’t just meeting an ancient creature - they’re meeting an individual with a history written in its bones.



The full study was published in the journal <a href="https://sjpp.springeropen.com/articles/10.1186/s13358-025-00368-3">Swiss Journal of Palaeontology</a>.



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220-million-year-old Plateosaurus dinosaur died from a crippling bone infection

Every visitor to the Natural History Museum in Zurich is...

Bluebottles - also known as Portuguese man o' war - are jellyfish-like marine creatures with long, stinging tentacles that often wash up on beaches. It's been widely assumed that bluebottles all belong to a single species, but a new global genetic survey has revealed otherwise.



Dr. Samuel H. Church of <a href="https://www.yale.edu/" target="_blank" rel="noreferrer noopener">Yale University</a> coordinated the genome work with Australian colleagues, including Professor Kylie Pitt from Griffith University. Their findings overturn two centuries of scientific classification.



<h2 class="wp-block-heading" id="h-understanding-bluebottles-the-basics">Understanding bluebottles - the basics</h2>



The Portuguese man o’ war (Physalia physalis is the main species name), also known as the bluebottle, is a siphonophore - not a <a href="https://www.earth.com/news/world-jellyfish-day-2024-protecting-the-health-of-our-oceans/">true jellyfish</a>, although it closely resembles one. 



What makes it extraordinary is that it’s not a single organism but a colonial one - comprised of genetically identical individuals called zooids. 



Each zooid performs a specialized role: one floats, another captures prey with stinging tentacles, a third digests, and yet another reproduces. 



These zooids function together as if they were one being, demonstrating a remarkable example of biological division of labor and cooperative survival.



This organism’s iconic translucent float, or <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/pneumatophores" target="_blank" rel="noreferrer noopener">pneumatophore</a>, sits atop the water like a small sail, catching the wind to move it across the ocean’s surface. 



Beneath it trail long, venomous tentacles - sometimes over 30 feet - that contain specialized cells called nematocysts, which fire harpoon-like structures to inject potent venom into prey. 



Despite its beauty, the sting can be extremely painful to humans and potentially dangerous, though rarely fatal. The man o’ war plays a critical ecological role in <a href="https://www.earth.com/news/how-the-sharks-body-grows-with-geometric-precision/">pelagic food webs</a>, preying on small fish and plankton while serving as food for predators like the blanket octopus and loggerhead turtle.



<h2 class="wp-block-heading" id="h-four-species-of-bluebottles">Four species of bluebottles</h2>



The team sorted the <a href="https://oceanservice.noaa.gov/facts/portuguese-man-o-war.html" target="_blank" rel="noreferrer noopener">specimens</a> into Physalia physalis, P. utriculus, P. megalista, and a newly named Physalia minuta, the last discovered in waters south of New Zealand. Each species carries distinctive sail colors and float shapes - traits once dismissed as harmless variation.



Genetic markers show the four <a href="https://www.earth.com/news/world-jellyfish-day-2024-protecting-the-health-of-our-oceans/">lineages</a> do not interbreed, even when they occupy the same stretch of ocean. This pattern means evolution is at work in the open sea, not only along coastlines or around islands.



“We were shocked, because we assumed they were all the same species,” said Professor Pitt. Her remark echoes a long‑held textbook view now overturned.



Every colony is a <a href="https://twilightzone.whoi.edu/explore-the-otz/creature-features/siphonophore/" target="_blank" rel="noreferrer noopener">siphonophore</a> - a floating commune of genetically identical zooids that act as one animal. The arrangement lets a bluebottle grow long feeding tentacles while the gas‑filled float keeps the colony at the surface, a lifestyle that defines the <a href="https://theoceancleanup.com/updates/neuston-in-the-great-pacific-garbage-patch-and-the-impact-of-cleanup/" target="_blank" rel="noreferrer noopener">neuston</a> layer.



<h2 class="wp-block-heading" id="h-differences-beyond-appearance">Differences beyond appearance</h2>



Raw genomes alone rarely hint at an animal’s appearance, so the researchers combed through 4,000 beach photographs. Color signatures and sail angles in the pictures matched the genetic <a href="https://www.earth.com/news/giant-phantom-jelly-discovered-exposed-ecosystem-under-antarctic-iceberg/">lineages</a> one by one.



Citizen scientists had, in effect, been taking field notes for years without knowing it. Their uploads supplied location data that helped map where each species turns up during different wind seasons. 



Machine‑learning tools flagged subtle differences, such as a deep‑purple crest on P. megalista or the small, clear float on P. minuta. Laboratory vouchers later verified those traits under a microscope.



The public photo trove also clarified left‑handed versus right‑handed sails, a feature that decides which way a bluebottle is blown. Such handedness now appears tied to species identity rather than simple developmental chance.



<h2 class="wp-block-heading" id="h-ocean-currents-separate-bluebottle-species">Ocean currents separate bluebottle species</h2>



<a href="https://www.earth.com/news/jellyfish-more-than-just-a-snack-for-predatory-fish/">Ocean</a> circulation models recreated likely drift paths from hatchling to adult, revealing corridors that keep populations apart. 



Prevailing winds in the Pacific sweep P. utriculus west toward Australia, while the South Equatorial Current loops P. megalista into the Atlantic. 



The new species, P. minuta, hugs eddies of the <a href="https://www.sciencedirect.com/science/article/abs/pii/S0924796319300259" target="_blank" rel="noreferrer noopener">Tasman Front</a>, a route that spirals larvae southward before they ever cross open ocean. Because gonads detach and sink below the surface to spawn, deep water layers also partition gene flow.



Subtle climate shifts could shuffle these corridors and mix the species in the future, but for now the lines stay crisp. That stability gives evolutionary forces room to sculpt body size, venom genes, and reproductive timing without interference. 



The finding challenges a common idea that wind‑powered drifters form one gigantic, well‑mixed population. Instead, even a creature built for travel can remain genetically provincial.



<h2 class="wp-block-heading" id="h-bluebottle-stings-vary-by-species">Bluebottle stings vary by species</h2>



<a href="https://sls.com.au/bluebottlewatch-a-new-research-project-to-develop-a-bluebottle-prediction-tool-for-our-beaches/" target="_blank" rel="noreferrer noopener">Surf Life Saving Australia</a> ranks bluebottle contact as a leading reason for first‑aid calls, spurring a research grant to build a beach sting forecast. 



Knowing which species is likely to arrive could sharpen those alerts, because tentacle length and venom chemistry differ among the four.



During the summer of 2017, more than <a href="https://www.abc.net.au/news/2017-03-01/bluebottle-stings-up-900-per-cent-in-queensland/8313970" target="_blank" rel="noreferrer noopener">38,000 people</a> were treated for bluebottle stings in Queensland alone - a spike of 900 percent over the prior season. 



<h2 class="wp-block-heading" id="h-forecasting-bluebottle-seasons">Forecasting bluebottle seasons</h2>



Public health planners can now add species identity to their toolbox instead of relying on wind direction alone.



Lighter winds often carry the smaller P. minuta onto sheltered south‑facing bays, where novice swimmers gather. 



Lifeguards armed with species‑level forecasts might adjust patrols or signage accordingly. Thermal anomalies that favor jellyfish blooms may not boost every bluebottle equally, given their genetic split.



Future sting seasons could therefore hinge on which lineage catches the breeze rather than on sheer water temperature.



<h2 class="wp-block-heading" id="h-hidden-population-structure-in-the-ocean">Hidden population structure in the ocean </h2>



The bluebottle story joins other case studies of copepods and pteropods that show hidden population structure in the high seas. 



Collectively, these results overturn the old axiom that “everything is everywhere” once an organism can drift. Marine cleanup projects often claim surface life is sparse, implying little ecological risk when skimming plastics. 



Evidence of partitioned diversity urges far more caution before nets sweep across convergence zones.



<h2 class="wp-block-heading" id="h-why-does-any-of-this-matter">Why does any of this matter?</h2>



Pharmaceutical scouts have isolated novel peptide toxins from P. physalis, but untapped species may hold different compounds with medical promise. A four‑species framework sets a clearer path for bioprospecting teams.&nbsp;



Climate models aiming to forecast <a href="https://www.earth.com/news/marine-robots-are-exploring-the-oceans-role-in-climate-control/">oceanic carbon</a> cycling need accurate species counts because each colony’s buoyant gas is nearly 13 percent carbon monoxide. Four distinct production rates could alter estimates of gas exchange at the air–sea interface.



Researchers who track long‑range migrants, from sea turtles to seabirds, can now refine diet studies. Predator scat may tell which bluebottle species dominates a given flyway, adding another layer to ecosystem maps.



<h2 class="wp-block-heading" id="h-toxin-genes-in-bluebottle-species">Toxin genes in bluebottle species </h2>



Work is already under way to test whether the four lineages differ in toxin genes, an angle that could explain regional differences in sting severity. 



Another puzzle lies in the handedness trait, which might be hardwired by alleles rather than molded by early winds.



Field biologists plan to tag floats with tiny temperature loggers to see how much time each species spends in sun‑baked surface water. Results should reveal whether thermal tolerance helped split the lineages in the first place.



The study is published in the journal <a href="https://www.cell.com/current-biology/abstract/S0960-9822(25)00682-7" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Biologists discover that the "Portuguese man o' war" has multiple species

Bluebottles - also known as Portuguese man o' war -...

Child-directed speech, also known as “baby talk,” plays a vital role in human development. Around the world, caregivers use a distinct vocal style to talk to infants. 



These modified speech patterns help young minds absorb vocabulary and structure. But how did this behavior originate? Could it have evolved from our primate ancestors?



A recent study led by researchers from the <a href="https://www.uzh.ch/en.html" target="_blank" rel="noreferrer noopener">University of Zurich</a>, <a href="https://www.unine.ch" target="_blank" rel="noreferrer noopener">University of Neuchâtel</a>, and collaborators across Europe and the U.S. offers new insights. 



The research, published in the journal Science Advances, explores whether great apes use infant-directed vocalizations like humans do.



<h2 class="wp-block-heading" id="h-baby-talk-in-humans-and-apes">Baby talk in humans and apes</h2>



The team observed wild populations of bonobos, chimpanzees, gorillas, and orangutans. They also included data from human infants across diverse cultures: Shipibo-Konibo, Qaqet, Chintang, and Tuatschin.



To quantify communication, they analyzed vocal behavior during two-minute intervals. They categorized each instance as infant-directed, surrounding, or general vocal activity. 



They followed immature individuals closely, noting all relevant sounds from nearby group members.



<h2 class="wp-block-heading" id="h-humans-use-baby-talk-way-more">Humans use baby talk way more</h2>



These results highlight how unique human caregiving behavior is compared to that of our closest relatives. Human <a href="https://www.earth.com/news/how-do-infants-connect-with-the-world-it-all-starts-with-the-feet/">infants</a> are surrounded by vocal input that is not only frequent but also specifically tailored to them. This level of attention likely helps them learn language faster and more efficiently.



Even when focusing only on what mothers said, humans stood out. Mothers spoke directly to their babies far more than ape mothers did. In fact, the difference between human and bonobo mothers was over 400-fold.



Most of the speech around human infants was directed at them. In contrast, great apes showed almost no such targeted communication. 



This suggests that humans may have evolved a special way of teaching language that relies heavily on speaking directly to infants.



<h2 class="wp-block-heading" id="h-not-just-direct-speech">Not just direct speech</h2>



Surrounding speech refers to vocalizations that infants can hear but are not directly addressed to them. This type of input was fairly consistent across humans, <a href="https://www.earth.com/news/chimpanzees-select-the-best-materials-for-termite-fishing/">chimpanzees</a>, and bonobos. 



These species likely live in more socially active environments, where infants overhear conversations or calls.



Orangutans, however, received much less surrounding speech. This fits their more solitary lifestyle, where fewer individuals are nearby to produce vocalizations.



Because infant-directed speech is rare among apes, they may depend more on what they hear in the background. This ambient input could help them learn communication patterns, even without being directly taught.



<h2 class="wp-block-heading" id="h-baby-talk-helped-humans-evolve">Baby talk helped humans evolve</h2>



The data suggest a sharp evolutionary shift. “Our findings suggest that the tendency to direct vocalizations at infants... has been massively expanded in the human lineage,” the authors wrote.



One possible driver is the need to transmit learned communication. Unlike apes, human language is highly flexible and requires teaching. Infant-directed speech helps children grasp words, tone, and context more easily.



Interestingly, gestures may play a more prominent role in great apes. Repetitive <a href="https://www.earth.com/news/wild-bird-uses-wing-gestures-to-politely-say-after-you/">gestures</a> in apes mirror some features of human baby talk. These findings hint that vocal and gestural teaching modes may have evolved in parallel.



<h2 class="wp-block-heading" id="h-are-humans-alone-not-quite">Are humans alone? Not quite</h2>



Other species also engage in infant-directed communication. Dolphins change pitch when around calves. Bats alter calls to suit pups. Cats and monkeys use specific sounds to call or calm infants.



However, these communications likely serve different functions, like identification or retrieval. Only in humans do these vocal patterns appear tightly linked to complex language learning.



<h2 class="wp-block-heading" id="h-studying-apes-to-understand-ourselves">Studying apes to understand ourselves</h2>



The study opens up new paths. The researchers propose exploring who produces surrounding speech in ape societies, siblings, mothers, or others, and whether that affects learning.



Additionally, they call for deeper study of ape gestures directed at infants. “The gestural modality might represent an additional fruitful avenue for future work."



This research provides strong support that child-directed speech may have evolved to support <a href="https://www.earth.com/news/babies-can-naturally-learn-multiple-languages-from-birth/">language learning</a>. Our ancestors likely began with ambient communication, then shifted toward more intentional, tailored speech as language grew more complex.



By comparing the way species talk, or don’t talk, to their young, we gain a clearer view of what makes human language so powerful and so unique.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.adt7718" target="_blank" rel="noreferrer noopener">Science Advances</a>.



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Baby talk may explain what sets humans apart from apes

Child-directed speech, also known as “baby talk,” plays a vital...

The monarch may steal the spotlight, yet an ongoing crisis is affecting nearly every butterfly <a href="https://www.earth.com/news/butterflies-can-adapt-quickly-but-evolution-has-its-limits/">species</a> in the lower 48. Between 2000 and 2020, total abundance fell by 22 percent, according to the largest survey ever assembled.



That national <a href="https://naba.org/wp-content/uploads/2025/03/Rapid-butterfly-declines-across-the-United-States-during-the-21st-century_Science_03072025.pdf" target="_blank" rel="noreferrer noopener">dip</a> works out to 1.3 percent each year, a slow‑motion slide that rarely makes headlines but never takes a day off.



<h2 class="wp-block-heading" id="h-butterfly-species-decline-and-habitat-loss">Butterfly species decline and habitat loss</h2>



Roughly a third of the 342 <a href="https://www.earth.com/news/butterfly-migration-habits-are-not-determined-by-their-dna/">species</a> with solid data are shrinking fast, and 107 have already slipped by more than half of their former counts. 



Habitat carved into parking lots, hotter summers driven by climate change, and heavy use of pesticides each gnaw at different life stages, yet together they form a three‑pronged squeeze.



Even the unglamorous caterpillar matters here: without the right host leaves, no egg survives, no adult emerges, and no pollination happens. 



Cheryl Schultz of <a href="https://wsu.edu/">Washington State University</a> helped write the new recovery roadmap. She says the clock is ticking for the insects she has studied for three decades.



<h2 class="wp-block-heading" id="h-long-term-drop-in-butterfly-numbers">Long-term drop in butterfly numbers</h2>



The Science team pulled 12.6 million field observations from 76,000 surveys, then wrangled conflicting protocols into one set of trend lines.



Patterns varied by region, but the Southwest stood out as hardest hit, while the Pacific Northwest held steady only because one irruptive tortoiseshell species briefly boomed.



The authors stress that <a href="https://www.earth.com/news/butterfly-hovering-technique-could-revolutionize-drone-design/">butterflies</a> act as living barometers: when they vanish, so do many less‑monitored insects doing similar ecological work. 



Losing butterflies also removes food for birds and other wildlife that depend on soft‑bodied prey each spring.



<h2 class="wp-block-heading" id="h-cleaning-data-to-track-real-trends">Cleaning data to track real trends</h2>



Tracking butterfly abundance across hundreds of species isn't easy. Observations often come from community science platforms like iNaturalist, where users sometimes upload misidentified species or report tropical butterflies from butterfly houses as wild sightings.



To clean the data, researchers used <a href="https://txtav.com/en/range-map" target="_blank" rel="noreferrer noopener">range maps</a> to flag out-of-place records and exclude bad data from their models. 



Eliza Grames, an assistant professor at <a href="https://www.binghamton.edu/">Binghamton University</a>, said this step was key to making sure the trends reflected actual changes in nature rather than errors in reporting. Professor Grames specializes in using <a href="https://libguides.uta.edu/quantitative_and_qualitative_research/quant" target="_blank" rel="noreferrer noopener">quantitative methods</a>, evidence synthesis, and long-term datasets to understand how climate, habitat loss, and species interactions are affecting biodiversity. 



Her work focuses on combining scattered data sources like historical surveys and citizen science to track insect declines and guide effective conservation.



<h2 class="wp-block-heading" id="h-restoring-habitats-for-butterfly-species">Restoring habitats for butterfly species</h2>



Scott Black is the director of the <a href="https://www.xerces.org/">Xerces Society</a> and a co‑author of the recovery roadmap.



"Butterflies need host plants on which to lay eggs, wildflowers on which to feed, a refuge from pesticides, and sites to overwinter. There is hope for these animals if we focus on providing habitat for butterflies across all landscapes,” said Black. 



Providing season‑long bloom is key, and <a href="https://xerces.org/pollinator-conservation/habitat-restoration/management" target="_blank" rel="noreferrer noopener">Xerces</a> maintains region‑specific plant lists that match native flowers with local nectar feeders.



Land managers are urged to skip blanket spraying and instead spot‑treat weeds, mow outside bloom windows, and leave leaf litter for overwintering adults or chrysalids. 



Protecting habitat also buffers butterflies against flash droughts and early frosts that are becoming more common as weather swings widen.



<h2 class="wp-block-heading" id="h-green-spaces-support-butterfly-species">Green spaces support butterfly species</h2>



The recovery roadmap emphasizes that conservation must happen everywhere, not just in protected wilderness. Even small green spaces can play a huge role when stitched together across cities, suburbs, and farms.



Pollinator corridors, like roadside flower strips or native plant buffers on farmland, let butterflies travel, feed, and lay eggs without interruption. 



When neighbors and land managers coordinate efforts, isolated patches of habitat can become a functioning network that supports entire species.



<h2 class="wp-block-heading" id="h-butterfly-species-and-cotton-yields">Butterfly species and cotton yields</h2>



Economics add weight to conservation: research in <a href="https://cns.utexas.edu/news/research/supporting-pollinators-could-have-big-payoff-texas-cotton-farmers" target="_blank" rel="noreferrer noopener">Texas</a> shows that <a href="https://www.earth.com/news/national-learn-about-butterflies-day-an-enchanting-world-awaits/">butterflies</a> translate into about $100 million in annual pollination value for cotton alone.



When rows of nectar plants bordered the fields, cotton set more bolls, and farmers noticed a boost in yield without another drop of chemical inputs.



<h2 class="wp-block-heading" id="h-how-to-help-butterfly-species">How to help butterfly species</h2>



Homeowners can swap a slice of turf for milkweed, asters, and goldenrod. City planners can seed bloom strips along bike paths and medians instead of short mowed grass.



Rural roadsides double as corridors when mowing heights stay above six inches and herbicide use is limited to targeted patches, a change that costs little but scales quickly.



Even small pollinator islands in solar arrays or utility rights‑of‑way create stepping‑stones that let populations recolonize after drought or fire.



Success stories already exist. The Fender’s blue butterfly, once presumed lost, bounced back enough for the <a href="https://oregoncapitalchronicle.com/2023/10/16/pink-wildflower-in-oregon-and-southwest-washington-removed-from-federal-protection/" target="_blank" rel="noreferrer noopener">U.S. Fish &amp; Wildlife Service</a> to reclassify it from endangered to threatened in 2023.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adp4671" target="_blank" rel="noreferrer noopener">Science</a>.



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Butterfly species are declining fast across the United States

The monarch may steal the spotlight, yet an ongoing crisis...

Relocating elephants to fresh herds can boost genetics and social health - but what if the animals can’t “talk” to their new hosts? 



Field biologists have discovered that elephant groups separated by only a few hundred miles emit subtly different low-frequency rumbles. Those dialects might complicate friendships, alliances, or alarm calls when animals are translocated. 



The puzzle is part of a broader realization that many species possess local traditions - learned behaviors that function much like human culture.



To help researchers explore that idea, scientists at the <a href="https://www.arizona.edu/">University of Arizona</a> have launched the first open-access, global catalog of animal <a href="https://www.earth.com/news/saving-the-cultural-legacy-of-wild-animals/">cultures</a>.



<h2 class="wp-block-heading" id="h-mapping-animal-cultures">Mapping animal cultures</h2>



The <a href="https://viz.datascience.arizona.edu/ACDB/">Animal Culture Database</a> brings together hundreds of peer-reviewed reports on socially learned behaviors - from whales’ evolving migration routes to chimpanzees’ stone-tool know-how.



Kiran Basava is the paper’s lead author and a postdoctoral research associate at the University of Arizona.



“There is a consensus among animal behavior researchers that cultural traditions and socially learned behaviors are important to conservation,” said Basava. "There are decades of research investigating these behaviors across different species that are scattered throughout the literature."



"We synthesized that work to facilitate creative research and discussions about how culture is defined across different species, as well as how animals respond to different environmental disturbances caused by humans.”



<h2 class="wp-block-heading" id="h-animal-culture-by-region">Animal culture by region</h2>



The database centers on an interactive world map dotted with pins. Click on a marker and you can read about orangutans’ nesting tricks in Borneo, humpback <a href="https://www.earth.com/news/hidden-patterns-in-whale-songs-predict-ecosystem-shifts/">whales</a>’ complex songs off Tonga, or urban crows that drop nuts at traffic lights so cars will crack them open.



A search panel lets visitors filter by species, behavior type, or geographic region. For example, it reveals how rats in European forests learned to peel pinecones, or how certain <a href="https://www.earth.com/news/some-birds-trick-their-way-into-mating-by-removing-testosterone-from-their-bodies/">birds</a> remodeled mating dances after wildfires changed their habitat.



<h2 class="wp-block-heading" id="h-building-a-living-archive">Building a living archive</h2>



To assemble the resource, Basava and colleagues combed through thousands of journal articles published over several decades. 



The experts screened more than 1,000 promising papers. From those, they coded 121 into the pilot version - covering 30 mammalian, 30 avian, and one insect species. The team is adding 600 more studies and will soon let other scientists upload their own findings.



Study co-author Cristian Román-Palacios, an assistant professor of information science, said the tool could transform how researchers study cultural evolution.



“You can investigate the origins of culture by not just tracing it back to humans, but by seeing how much variance there is between different species and asking what drives those differences,” explained Professor Román-Palacios.



“Culture is not just a human phenomenon, and this database can help investigate what drives culture across the animal kingdom.”



<h2 class="wp-block-heading" id="h-cultural-loss-risks-extinction">Cultural loss risks extinction</h2>



Understanding animal culture is more than academic curiosity. Conservationists are realizing that an <a href="https://www.earth.com/news/elephants-may-be-the-first-non-human-animals-to-call-each-other-by-names/">elephant dialect</a>, a whale migration route, or a songbird melody can be as crucial as genetics for a population’s survival.



Human-driven habitat loss, noise pollution, and climate change threaten to erase those traditions. If relocated elephants cannot communicate with resident herds, or if dam construction blocks a salmon run taught across generations, restoration projects may fail.



By pooling case studies in one searchable hub, the database helps practitioners identify culturally important behaviors that need protection - much like <a href="https://www.unesco.org/en">UNESCO</a>’s list of human cultural heritage.



The data can also reveal patterns: Are populations with richer cultural repertoires more resilient to disturbance? Do species that lose key traditions decline faster?



<h2 class="wp-block-heading" id="h-science-meets-animal-tradition">Science meets animal tradition</h2>



The experts hope educators will use the site to teach evolutionary biology, while data scientists mine the entries for global trends. Basava envisions adding tools to visualize how behaviors spread over time, akin to epidemiological models for disease.



Future iterations may incorporate audio clips of vocalizations or video of <a href="https://www.earth.com/news/some-fish-use-tools-to-crack-open-prey/">tool use</a>, creating a multimedia atlas of animal ingenuity. 



The designers also plan multilingual interfaces to attract contributions from researchers worldwide, including Indigenous observers whose knowledge often predates academic studies.



<h2 class="wp-block-heading" id="h-culture-isn-t-just-human">Culture isn’t just human</h2>



The project resonates with a paradigm shift in biology: culture is no longer viewed as uniquely human. 



From dolphins that pass down signature whistles to capuchin monkeys that adopt local grooming fashions, <a href="https://www.earth.com/news/food-availability-influences-social-learning-among-orangutans/">social learning</a> pervades the animal kingdom. Recognizing those parallels can inform debates about animal welfare and cognitive rights, the authors note.



And it may reshape how humans see ourselves. If elephants currently need a translator, perhaps conservation must consider not just where animals live. It should also account for how they live - their languages, crafts, and customs forged over millennia.



For now, the Animal Culture Database offers anyone with an internet connection a front-row seat to those hidden worlds. The database preserves animal-taught traditions and reminds us that culture extends beyond just the human species.



The study is published in the journal <a href="https://www.nature.com/articles/s41597-025-05315-y">Nature Scientific Data</a>.



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From rumbles to rituals: Scientists map the cultures of the animal kingdom

Relocating elephants to fresh herds can boost genetics and social...

Bird species add color, movement, and sound to our world. They pollinate plants, control pests, and spread seeds. But their future is in danger.



A new study from the <a href="https://www.reading.ac.uk" target="_blank" rel="noreferrer noopener">University of Reading</a> warns that climate change and habitat destruction threaten global bird diversity. 



The loss of unique birds like the bare-necked umbrellabird, helmeted hornbill, and yellow-bellied sunbird-asity would shrink the variety of bird forms that support <a href="https://www.earth.com/news/big-brains-and-wide-ranges-cant-save-birds-from-climate-change/">ecosystems</a>.



This projection triples all recorded bird extinctions since 1500 CE. Even with protection from hunting, habitat loss, and climate change, 250 species may still disappear. Some birds are now too fragile to survive without direct help.



“Many birds are already so threatened that reducing human impacts alone won't save them. These species need special recovery programs, like breeding projects and habitat restoration, to survive,” explained Kerry Stewart, lead author of the study.



“We face a bird extinction <a href="https://www.earth.com/news/birds-are-struggling-to-keep-pace-with-a-warming-climate/">crisis</a> unprecedented in modern times. We need immediate action to reduce human threats across habitats and targeted rescue programs for the most unique and endangered species.”



<h2 class="wp-block-heading" id="h-large-bird-species-are-most-at-risk">Large bird species are most at risk</h2>



The researchers studied nearly 10,000 bird species using IUCN Red List data and advanced models. 



The results showed that large-bodied birds are especially at risk. These birds struggle more with hunting pressure and climate stress. Birds with broad wings face severe danger from habitat destruction, especially in forests.



The study went beyond just species counts. It measured the expected loss of “functional diversity,” a term describing the variety of bird shapes, diets, and behaviors. 



Under current trends, global bird functional diversity could fall by about 3.2% in the next 100 years. This drop may sound small, but it would seriously damage ecosystems. 



Large, distinct <a href="https://www.earth.com/news/bird-evolution-timeline-pushed-back-20-million-years-by-baminornis-zhenghensis-discovery/">species</a> often provide unique services. Their disappearance would leave functional gaps that smaller or similar birds cannot fill.



<h2 class="wp-block-heading" id="h-limits-of-protection-alone">Limits of protection alone</h2>



The researchers tested three future scenarios: complete, partial, and minimal threat abatement. In the best case, where all human threats were removed across species ranges, around 250 species would still go extinct. That is nearly half of all projected losses, even with ideal conservation.



Some birds, like the Cebu flowerpecker, remain highly vulnerable despite facing few listed threats. With fewer than 70 individuals left, they may vanish without specific recovery steps like habitat restoration or captive breeding.



The study shows that reducing threats is not enough. Many species are already too close to the brink. Past damage, small populations, and isolated habitats all contribute to ongoing <a href="https://www.earth.com/news/birds-are-molting-earlier-in-the-fall-as-seasons-shift/">risks</a>.



<h2 class="wp-block-heading" id="h-threats-to-rare-bird-species">Threats to rare bird species</h2>



The research evaluated six main threats: habitat loss, hunting, climate change, invasive species, disturbance, and pollution. 



Habitat loss contributed the most to species decline, affecting over 1,600 species. Yet when it comes to preserving unique bird traits, other threats matter more.



Driver-specific results showed that reducing hunting or accidental deaths helped conserve rare bird features more effectively, even if fewer total species were saved. That means some threats disproportionately affect birds with uncommon traits.



Birds with long tails and short beaks, for example, benefited more from reduced hunting. Birds with broad wings responded better to protection from habitat destruction. These patterns help tailor conservation actions to bird traits most at risk.



<h2 class="wp-block-heading" id="h-strategic-recovery-of-unique-species">Strategic recovery of unique species</h2>



One solution stood out: target the most unique birds for rescue. The researchers created a list of 200 functionally unique species. Protecting just the top 100 could conserve over two-thirds of global bird functional diversity.



These birds include nectar-feeders, scavengers, and seed dispersers. From the Sulu hornbill to the southern royal albatross, many are island-dwelling, wide-ranging, or limited to one location. They carry traits that help regulate temperature, shape ecosystems, and fill rare ecological roles.



Preventing the extinction of around 37 of these birds could achieve this 68% protection goal. Since past efforts have already saved 21 to 32 bird species since 1993, this new goal appears feasible with commitment.



<h2 class="wp-block-heading" id="h-what-must-be-done-now">What must be done now</h2>



Even in optimistic futures, threats cannot be erased quickly or completely. Species recovery programmes, including in-situ and ex-situ measures, are needed for the most vulnerable.



“Stopping threats is not enough,” said Professor Manuela Gonzalez-Suarez. “Prioritizing conservation programs for just 100 of the most unusual threatened birds could save 68% of the variety in bird shapes and sizes. This approach could help to keep ecosystems healthy.”



Habitat protection remains key. But to safeguard ecosystem resilience, conservationists must also think about functional diversity, not just species counts.



The coming century will test humanity’s will to preserve Earth's avian legacy. Without sharp decisions and bold action, we risk losing many birds and the ecological balance they help maintain.



The study is published in the journal <a href="https://www.nature.com/articles/s41559-025-02746-z" target="_blank" rel="noreferrer noopener">Nature Ecology &amp; Evolution</a>.



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Hundreds of bird species could vanish in the next century

Bird species add color, movement, and sound to our world....

Anyone who has watched a cat sleep knows they do so with remarkable consistency. From curled tails to neatly tucked paws, their resting positions often seem almost ritual-like. But new research suggests the sleeping positions of cats are not just habits.



A global research team has found that most <a href="https://www.earth.com/news/cats-can-tell-people-apart-by-sniffing-them/">cats</a> prefer to sleep on their left side. By analyzing 408 YouTube videos, the researchers confirmed a significant bias toward this sleeping position. 



About 65% of the cats were seen resting with their left shoulder down, while only 35% chose the right side. "Sleeping on the left side can therefore be a survival strategy,” noted the researchers.



<h2 class="wp-block-heading" id="h-cats-sleep-left-to-react-faster">Cats sleep left to react faster</h2>



When a cat sleeps on its left, it wakes up using its left visual field. This field is processed in the brain’s right hemisphere, which handles spatial awareness, fear response, and fast movement coordination. 



“Asymmetries in behavior can have advantages because both hemispheres of the brain specialize in different tasks,” explained study co-author Onur Güntürkün.



Left-side sleeping allows cats to respond faster to threats from below or from the left. This sleep posture aligns with <a href="https://www.earth.com/news/international-lynx-day-2025-protecting-the-silent-hunters/">cats</a>’ tendency to rest in high places. 



Elevated locations limit predator access and provide better visibility. Combined with leftward sleeping, this may give cats a stronger edge when suddenly waking.



<h2 class="wp-block-heading" id="h-a-strong-left-side-bias">A strong left-side bias</h2>



The team examined only clear, unaltered videos showing single <a href="https://www.earth.com/news/how-and-why-do-cats-purr-scientists-finally-found-the-answers-genetic-dna/">cats</a> lying fully visible on one side for at least 10 seconds. Videos that were mirrored, low-resolution, or cropped were excluded. 



The results were statistically significant (χ² = 37.7, df = 1, p &lt; 0.001), showing a clear left-side preference.



This bias may not be random. It fits well with patterns seen in many species, where the right brain hemisphere plays a major role in detecting danger. 



Animals generally react faster to threats coming from their left side, suggesting an adaptive benefit to this positioning.



<h2 class="wp-block-heading" id="h-the-right-brain-helps-detect-danger">The right brain helps detect danger</h2>



“By specializing on one limb or one side of its sensory system, the contralateral hemisphere goes through life-long cycles of motor and perceptual learning,” wrote the study authors.



This helps speed up brain processing, cut down reaction times, and enhance accuracy. Sleeping with the left shoulder down lets the brain’s stronger threat-response side engage instantly when the cat awakens.



The right amygdala, which helps process fear, is more active in the right side of the brain. Since the right side also handles things like noticing space and spotting danger, this supports the idea that sleeping on one side may be linked to fear.



<h2 class="wp-block-heading" id="h-other-causes-for-cat-sleep-bias">Other causes for cat sleep bias</h2>



Could other factors influence sleep position? Maybe, but they are unlikely to change the overall pattern. For instance, pregnant cows lie on their left with moderate frequency. However, pregnancy rates alone cannot explain the strong leftward bias in this cat sample.



Another possible explanation is “pawedness,” preference for using one paw over the other. Around 78% of cats show some degree of paw preference. But left- and right-pawed cats occur in equal numbers. So paw dominance does not match the 65% left-sleeping pattern seen here.



Still, researchers caution that more studies are needed. The team had no access to sex or pregnancy data for the cats in the videos. But the strong population-level trend remains clear.



<h2 class="wp-block-heading" id="h-cats-sleep-habits-reveal-brain-evolution">Cats sleep habits reveal brain evolution</h2>



This finding adds to the growing evidence that cats, like many <a href="https://www.earth.com/news/cats-have-become-one-of-the-worlds-most-invasive-predators/">animals</a>, use subtle behavioral traits to stay safe. It also supports broader patterns of brain lateralization seen across mammals and birds.



The researchers believe these insights can help researchers understand how such asymmetries emerge. 



“Although this finding is subject to debate, it could provide an excellent opportunity to study the emergence of asymmetries at the population level,” they wrote.



For pet owners and scientists alike, this sleepy behavior may offer surprising clues about how brains and bodies work together to enhance survival and adaptation.



The study was led by researchers from the&nbsp;<a href="https://www.uniba.it/" target="_blank" rel="noreferrer noopener">University of Bari Aldo Moro</a>,&nbsp;<a href="http://www.ruhr-uni-bochum.de/en" target="_blank" rel="noreferrer noopener">Ruhr University Bochum</a>,&nbsp;<a href="https://www.medicalschool-hamburg.de/" target="_blank" rel="noreferrer noopener">Medical School Hamburg</a>, and other international partners.



The study is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(25)00507-X" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Cats clearly prefer sleeping on their left side, here's why

Anyone who has watched a cat sleep knows they do...

For over a century, scientists have debated how mammals shifted from sprawling like reptiles to walking upright. This transition marked one of the most significant events in vertebrate evolution. It shaped how mammals, from bats to humans, move through their world.



While earlier views suggested a simple step-by-step progression, new research suggests a very different path. 



A study led by Dr. Robert Brocklehurst of the <a href="https://www.reading.ac.uk" target="_blank" rel="noreferrer noopener">University of Reading</a> shows that upright posture evolved through a complex branching <a href="https://www.earth.com/news/pet-dogs-severely-harm-wildlife-even-when-leashed/">process</a>.



<h2 class="wp-block-heading" id="h-evolution-of-upright-posture-in-mammals">Evolution of upright posture in mammals </h2>



“The evolution of mammals has previously been characterized as a series of steps from sprawling, to semi-sprawling, to upright,” said Dr. Brocklehurst. “However, what we discovered was a more nonlinear evolutionary progression throughout mammalian <a href="https://www.earth.com/news/dog-nose-shapes-could-help-explain-human-birth-defects/">history</a>.”



The researchers analyzed over 200 species of tetrapods. They compared humerus bones across fossilized synapsids and modern animals like salamanders, reptiles, monotremes, and upright mammals. 



The team examined traits such as bone length, torsion, bending strength, and muscle leverage.



Rather than showing a clear ladder of progress, the data revealed bursts of change. Different mammalian ancestors experimented with varying forelimb functions. These experiments shaped the eventual rise of upright walking.



<h2 class="wp-block-heading" id="h-mapping-the-mechanics-of-movement">Mapping the mechanics of movement</h2>



The researchers used a computational model to connect bone shape with function and posture. They created adaptive landscapes that linked bone mechanics to different walking <a href="https://www.earth.com/news/dogs-can-recognize-familiar-human-voices-even-in-recordings/">styles</a> - sprawled or upright.



“By correlating bone shape and limb biomechanics with posture, we could test how well the fossil bones were optimized for specific functional tasks, like upright walking versus sprawled walking,” said Dr. Brocklehurst.



“We expected to see a neat progression - from sprawling pelycosaurs to a bit more upright therapsids, then cynodonts, then fully upright mammals. Instead, we found bursts of innovation.”



The team discovered that while early synapsids did have sprawling limbs, they didn’t function like modern reptiles. 



“They’re not just copies of reptiles, but distinctive animals in their own right that are a little different from anything that’s alive today," said said Dr. Kenneth Angielczyk of the University of Chicago.



<h2 class="wp-block-heading" id="h-mammals-tried-many-movement-styles">Mammals tried many movement styles</h2>



This research challenges the idea of direct, staged transitions. Instead of rigid postural categories, the ancestors of <a href="https://www.earth.com/news/why-do-cats-outlive-dogs-clues-found-in-their-genes/">mammals</a> explored many forms of limb use.



“Previous hypotheses posit the synapsid ‘sprawling-parasagittal’ transition as a series of discrete postural shifts; our study supports the view of synapsid evolution as a series of successive radiations, with major clades exhibiting considerable functional (and postural) variation,” the researchers wrote.



“While the ancestors of mammals did generally get more upright as time went on, there was a lot of variation in each major group of mammalian ancestors.”



Professor Stephanie Pierce of <a href="https://www.harvard.edu" target="_blank" rel="noreferrer noopener">Harvard University</a> noted that the path to upright posture wasn’t a straight line. "The ancestors of mammals weren’t steps on a ladder with modern mammals at the top."



<h2 class="wp-block-heading" id="h-muscles-behind-mammalian-motion">Muscles behind mammalian motion</h2>



The upright posture of modern mammals required deep musculoskeletal changes. This included shifts in bone shape and how muscles interacted with the skeleton. 



The study showed that parasagittal posture - the fully upright limb arrangement - appeared relatively late in mammal history.



“Our work challenges the idea that posture changed gradually and early on,” said Professor Pierce. “Instead, it shows that upright posture and locomotion were a late evolutionary innovation, not an early defining trait of the mammalian lineage.”



“Understanding how mammals came to walk upright isn’t just about bones. It’s about uncovering the dynamic history of life on Earth," said Dr. Brocklehurst.



The researchers acknowledge some limitations in their study. These include uncertainties in evolutionary timelines and divergence dates. However, the large dataset and mechanical modeling provide a strong framework for future research.



<h2 class="wp-block-heading" id="h-tracing-upright-posture-in-mammals">Tracing upright posture in mammals</h2>



To compare hundreds of bones from vastly different animals, the team had to innovate. Traditional shape analysis tools failed. So, they retooled an R software package into a “slice-based” landmarking system.



This approach allowed for precise measurement of traits even across species separated by millions of years. Former undergraduate Magdalen Mercado helped assemble the dataset, contributing to the massive scope of the project.



Professor Pierce reflected on the legacy of Harvard researchers who tackled similar questions decades ago. “Now, with new tools and data, we can revisit those ideas and see the story more clearly.”



“This delayed acquisition [of upright posture] ultimately laid the foundation for the extraordinary ecological success of mammals,” said Pierce.



<h2 class="wp-block-heading" id="h-new-chapter-in-mammalian-evolution">New chapter in mammalian evolution</h2>



This study is the first of its kind to use large-scale biomechanics to trace mammalian posture. It reveals that upright walking didn’t come early, but evolved after numerous experiments in movement.



As the team continues modeling limb function in fossil species, they aim to unlock more details about how ancient creatures lived and moved.



“The origin of upright mammalian posture is a key part of their evolutionary story,” said Dr. Brocklehurst. 



“People have been working on this problem for over 100 years. We knew we needed to see as many fossils as possible, and really get to grips with bone function and mechanics, not just shape.”



With this broader view, scientists now see evolution not as a tidy path, but as a dynamic landscape full of surprises.



The study is published in the journal <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003188" target="_blank" rel="noreferrer noopener">PLOS Biology</a>.



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Mammals tried different ways to move before walking upright

For over a century, scientists have debated how mammals shifted...

Gorillas, often thought of as ground dwellers, spend much more time in the trees than previously assumed. This finding from the Max Planck Institute challenges long-standing ideas about the anatomy and evolution of gorillas.



Western and Bwindi mountain <a href="https://www.earth.com/news/gorillas-are-digging-for-a-surprising-food-in-the-jungle-soil/">gorillas</a>, studied across Gabon and Uganda, were observed over many years. Even the largest males, weighing up to 170 kg, showed substantial tree use. 



Adult females in Loango spent 34% of their time in trees, while Bwindi females clocked 21%. That is a huge jump from the 7% figure for Virunga gorillas.



Study lead author Dr. Martha M. Robbins is a zoologist in the Department of Primate Behavior and Evolution at the <a href="https://www.eva.mpg.de/index/">Max Planck Institute</a> for Evolutionary Anthropology.



“Adult females spent 20% to 30% of their time in the trees, while silverbacks spent 18% to 20% of their time being arboreal, which is much more than 2 to 7% found previously in the Virunga mountain gorillas,” said Dr. Robbins.



<h2 class="wp-block-heading" id="h-different-gorillas-different-tree-habits">Different gorillas, different tree habits</h2>



The Virunga population shaped our early understanding of <a href="https://www.earth.com/news/some-gorillas-get-sick-from-being-too-social/">gorilla</a> habits. These highland gorillas live in fruit-scarce zones and rarely climb. But the new study included data from five groups in Bwindi and one in Loango, totaling nearly 5,200 observation days.



The findings are clear: tree use varies widely between populations. Even juveniles and subadults in Bwindi and Loango spent 32% to 43% of their time in trees - double the rate seen in Virunga’s younger gorillas.



The researchers also found that body size plays a role but does not prevent tree climbing. 



“This demonstrates that the large body size of gorillas is not necessarily a limiting factor to tree climbing and that gorillas can be just as arboreal as some chimpanzee populations,” said co-author Rhianna Drummond-Clarke.



<h2 class="wp-block-heading" id="h-climbing-is-not-just-about-fruit">Climbing is not just about fruit</h2>



The researchers expected fruit to be the main driver behind climbing. While gorillas did climb more while eating fruit, the full story is more complex. In Loango, adult females were more arboreal when eating leaves than fruit. In Bwindi, the reverse was true.



Even silverbacks, the heaviest individuals, climbed trees to eat fruit. At Bwindi, silverbacks were arboreal 82% of the time they ate fruit. But fruit formed just 14% of their diet, meaning most of their tree time involved eating leaves.



At Loango, gorillas often ate fallen fruit from the ground. This shows fruit-eating can be a terrestrial act too. Meanwhile, western gorillas also ate lots of tree leaves, about 30% of their diet, driving folivorous tree use, similar to some monkeys.



<h2 class="wp-block-heading" id="h-feeding-is-the-main-reason-to-climb">Feeding is the main reason to climb</h2>



What were the <a href="https://www.earth.com/news/male-infertility-humans-linked-same-genes-gorilla-small-penises/">gorillas</a> doing in trees? Mostly feeding. Adult female gorillas were far more likely to climb while feeding than when resting or traveling.



Even when eating nonfruit, Loango females climbed more than Bwindi ones. This likely reflects differences in diet and foraging strategy. The energy payoff from fruit seems to outweigh the climbing cost, especially for massive silverbacks.



Also, Loango females were heavier climbers than their Bwindi peers when not eating fruit. This surprising reversal shows that even leaf-seeking gorillas may spend considerable time off the ground.



<h2 class="wp-block-heading" id="h-what-this-means-for-ape-evolution">What this means for ape evolution</h2>



These results have big implications. <a href="https://www.earth.com/news/most-endangered-primate-species-identified-in-new-report/">Gorillas</a> have long been labeled as terrestrial because of their bulk and plant-heavy diets. But that view no longer holds. The study shows gorilla arboreality spans all life stages, from infants to adults.



That shift affects how we interpret the fossil record. Gorilla-like bones have been taken to suggest ground-based life. But frequent tree climbing changes the picture. 



“We demonstrate that large body size and a largely folivorous diet in apes are also consistent with frequent arboreality,” noted the study authors.



Studies of limb proportions and bone strength now suggest a range, from more tree-based western gorillas to more ground-based Virunga ones. 



This means our models of ancient human relatives may need adjustment. Gorilla-like features may not imply they lived solely on the ground.



<h2 class="wp-block-heading" id="h-gorillas-are-tree-climbers-not-just-walkers">Gorillas are tree climbers, not just walkers</h2>



Gorillas are not just forest-floor giants. They climb often and for various reasons. From feeding on leaves to exploring the canopy, these behaviors offer key insights into how apes, including humans, evolved.



Future research may look into how such large animals navigate trees. They might distribute their weight across branches or use special movement strategies, similar to orangutans or chimpanzees. 



This research opens new doors in our understanding of ape mobility and evolutionary history.



The study is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(25)00590-1" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Gorillas spend much more time in trees than we previously thought

Gorillas, often thought of as ground dwellers, spend much more...

When humans burst into laughter together, moods lift almost automatically. New research shows that a similar boost happens in our closest cousins.



An international team led by <a href="https://bloomington.iu.edu/">Indiana University</a> scientists has discovered that <a href="https://www.earth.com/news/bonobos-group-cohesion-common-enemy-effect-do-not-kill-inside-their-species/">bonobos</a> become more upbeat after hearing the giggles of their companions. This finding pushes the evolutionary history of positive emotions back millions of years.



<h2 class="wp-block-heading" id="h-laughter-changed-ape-choices">Laughter changed ape choices</h2>



To explore laughter’s influence, the researchers designed a cognitive-bias test often used in animal psychology to gauge optimism or pessimism.



First, they trained bonobos at the <a href="https://www.apeinitiative.org/">Ape Initiative</a> in Des Moines, Iowa, to recognize two kinds of boxes: black ones that always contained a delicious snack and white ones that were always empty.



Once the apes consistently chose black and ignored white, the experimenters introduced a third, ambiguous gray box. They then played one of two sounds: recorded bonobo laughter or a neutral control noise.



“We know that other apes, like chimpanzees, have contagious laughter during play," said lead author Sasha Winkler, a primatologist at <a href="https://duke.edu/">Duke University</a>. "We were wondering if that behavior could be explained by positive emotions produced from the sound itself.” 



If the bonobos felt a surge of good feeling after hearing laughter, the team expected them to treat the uncertain gray box as if it were the rewarding black one.



That is exactly what happened. “Think of it like the rose-colored glasses effect,” Winkler said. “The bonobos were much more likely to approach the gray boxes after hearing laughter, treating them like the rewarded boxes, and indicating a more optimistic expectation of finding a treat.”



<h2 class="wp-block-heading" id="h-tracing-optimism-to-our-ancestors">Tracing optimism to our ancestors</h2>



This study is the first experimental proof that great-ape laughter can shift mood and cognition the way human laughter does.



“The tendency to behave more optimistically after hearing laughter suggests that the sound alone induced a positive emotional state in bonobos,” said senior author Erica Cartmill, the director of Indiana University’s Cognitive Science Program.



“This is the first study of which we're aware to measure a positive affect shift in nonhuman primates from a brief experimental intervention.”



Great apes -&nbsp; bonobos, <a href="https://www.earth.com/news/what-wild-chimpanzees-can-teach-us-about-parenting/">chimpanzees</a>, gorillas, orangutans - all emit play calls that acoustically resemble human chuckles. Earlier work tied those sounds to a common evolutionary origin. The new findings add a cognitive twist.



“Our results suggest that laughter in other apes shares not only phylogenetic and behavioral similarities with human laughter but also perhaps some of the same cognitive-emotional underpinnings,” Winkler noted.



“This emotional contagion appears to have been present in the primate lineage long before the evolution of language.”



<h2 class="wp-block-heading" id="h-laughter-empathy-and-apes">Laughter, empathy, and apes</h2>



Emotional contagion is often described as a foundational element of <a href="https://www.earth.com/news/little-benjamina-the-oldest-evidence-of-social-empathy-in-humans/">empathy</a> - the capacity to share another’s feelings. As Winkler put it, “studies like ours can help to untangle the evolutionary building blocks of empathy, communication, and cooperation in humans.”



By revealing that a simple vocal cue can brighten outlooks in bonobos, the research suggests that the mechanisms linking social sound to positive mood were already in place in a common ancestor millions of years ago.



Cartmill added that the work answers a long-standing bias in emotion research. “Our emotions influence many aspects of cognition, including memory, attention, and decision-making, but research has historically focused on negative emotions with clear behavioral correlates, like <a href="https://www.earth.com/news/brain-pathway-discovered-that-suppresses-fear/">fear</a> and aggression.”



“We wanted to better understand the relationship between positive affect and cognition in our closest living relatives.”



<h2 class="wp-block-heading" id="h-kanzi-and-the-future-of-empathy">Kanzi and the future of empathy</h2>



The experiments involved four bonobos, including the celebrated language-using ape Kanzi, who recently passed away.



“I feel incredibly grateful to have had the opportunity to work with Kanzi while he was still alive,” Winkler said. 



“We hope this brings greater public awareness of the remarkable similarities between us and bonobos, who are an endangered species. We have so much to learn from these incredible animals.”



Future studies will test whether laughter exerts similar cognitive effects in chimpanzees and other primates. They will also explore how social context - for example, hearing laughs from friends versus strangers - modulates optimism.



For now, the discovery that bonobo giggles brighten expectations highlights a shared emotional heritage and hints that a simple laugh has been boosting group spirits since long before humans walked the Earth.



The study is published in the journal <a href="https://www.nature.com/articles/s41598-025-02594-8">Nature Scientific Reports</a>.



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Laughter lifts bonobo moods, offering clues to human emotion

When humans burst into laughter together, moods lift almost automatically....

Rodents don’t usually evolve overnight. Like most species, they change slowly through tiny shifts passed down over thousands or millions of years. But when the world changes fast, like it has in cities over the past century, some animals keep up. 



In fact, some animals even adapt to urbanization in real time. A team of researchers recently spotted signs of that kind of <a href="https://www.earth.com/news/invasive-species-are-driving-rapid-evolution/">rapid evolution</a>. The clues were found in hundreds of skills sitting quietly in drawers at the Field Museum in Chicago.



The skulls weren’t newly collected specimens - they spanned more than a century. And hidden in their measurements were subtle changes that told a bigger story.



By comparing the skulls of eastern chipmunks and eastern meadow voles collected over the past 125 years, scientists at the Field Museum uncovered signs of these animals adjusting to an increasingly <a href="https://www.earth.com/news/ants-can-effectively-adapt-to-urban-environments/">urban environment</a>.



<h2 class="wp-block-heading" id="h-a-time-machine-in-a-museum">A time machine in a museum</h2>



“Museum collections allow you to time travel,” said Stephanie Smith, a mammalogist and XCT laboratory manager at the Field Museum. 



"Instead of being limited to studying specimens collected over the course of one project, or one person’s lifetime, natural history collections allow you to look at things over a more evolutionarily relevant time scale.”



The Field Museum’s mammal collection includes over 245,000 specimens from around the world, but its home city is especially well represented. These Chicago-area animals offer a rare chance to study changes across both time and space - right in the scientists’ backyard.



“We’ve got things that are over 100 years old, and they're in just as good of shape as things that were collected literally this year,” said Smith. “We thought, this is a great resource to exploit.”



<h2 class="wp-block-heading" id="h-comparing-rodents-in-the-city-of-chicago">Comparing rodents in the city of Chicago</h2>



The team focused on two rodent species that still call Chicago home. <a href="https://www.earth.com/news/small-mammals-play-a-vital-role-in-maintaining-forest-health/">Chipmunks</a>, which live above ground and eat a wide range of food, and <a href="https://www.earth.com/news/social-behavior-of-voles-linked-to-oxytocin-levels/">voles</a>, which live underground and mostly stick to plants. The contrast between them was part of the point.



“We chose these two species because they have different biology, and we thought they might be responding differently to the stresses of urbanization,” said Anderson Feijó, assistant curator of mammals at the Field Museum.



Two interns with the Field Museum Women in Science program - Alyssa Stringer and Luna Bian - played a central role in the work. 



<h2 class="wp-block-heading" id="h-rodent-skulls-and-city-adaptations">Rodent skulls and city adaptations</h2>



The researchers measured the skulls of 132 chipmunks and 193 voles. The skulls hold clues about diet, body size, and even sensory abilities.



“From the skulls, we can tell a little bit about how animals are changing in a lot of different, evolutionary relevant ways - how they're dealing with their environment and how they're taking in information,” said Smith.



Stringer and Bian measured basic features of each rodent skull, like overall length and the length of the tooth rows. 



The researchers also used 3D scanning to digitally map 82 chipmunk and 54 vole skulls. This allowed them to compare tiny differences in shape across specimens using a method called geometric morphometrics.



The results revealed small but telling shifts. Chipmunks showed an increase in skull size, but their tooth rows got shorter. 



Voles developed smaller bony structures in their skulls that are tied to hearing. The changes weren’t random - but they also weren’t clearly linked to temperature or climate.



<h2 class="wp-block-heading" id="h-rodents-respond-to-a-louder-bigger-city">Rodents respond to a louder, bigger city</h2>



To dig deeper, the team used satellite data to track how the city grew over time. They looked at building coverage starting in the 1940s and matched those trends to the locations where specimens were collected. 



Older specimens came from areas known to be wild back then - or from downtown areas that were already developed.



“We tried very hard to come up with a way to quantify the spread of urbanization,” said Feijó. “We took advantage of satellite images showing the amount of area covered by buildings, dating back to 1940.”



<h2 class="wp-block-heading" id="h-changes-driven-by-urbanization">Changes driven by urbanization </h2>



<a href="https://www.earth.com/news/urbanization-is-a-threat-to-78-of-the-worlds-bird-species/">Urbanization</a>, not climate, seemed to drive the rodent skull changes. And the way each species adapted may reflect how it lives.



“Over the last century, chipmunks in Chicago have been getting bigger, but their teeth are getting smaller,” said Feijó. “We believe this is probably associated with the kind of food they're eating."



"They're probably eating more human-related food, which makes them bigger, but not necessarily healthier. Meanwhile, their teeth are smaller - we think it's because they're eating less hard food, like the nuts and seeds they would normally eat.”



As for the voles? The parts of their skulls that hold the inner ear - the auditory bullae - have shrunk. “We think this may relate to the city being loud - having these bones be smaller might help dampen excess environmental noise,” said Smith.



<h2 class="wp-block-heading" id="h-a-warning-not-a-win">A warning, not a win</h2>



It might be tempting to see this as a success story - rodents adjusting to city life. But the scientists see it differently. 



The adaptations may help, but they’re not necessarily positive. Smaller teeth and smaller ear bones are symptoms of change, not signs of health.



“These findings clearly show that interfering with the environment has a detectable effect on wildlife,” said Feijó.



“Change is probably happening under your nose, and you don't see it happening unless you use resources like museum collections,” said Smith.



The full study was published in the journal <a href="https://academic.oup.com/icb/advance-article-abstract/doi/10.1093/icb/icaf081/8158706?redirectedFrom=fulltext">Integrative and Comparative Biology</a>.



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Chicago’s rodents are evolving with the city

Rodents don’t usually evolve overnight. Like most species, they change...

species in Grapsidae

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