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What is Cadmium?

Humans have moved plants around the planet for centuries, both on purpose and by accident. Today, more than 16,000 vascular plant species have naturalized outside their native ranges. Most of this spread has occurred since the 1950s, particularly in regions with the greatest human footprint.



Some of these newcomers establish themselves quietly. Others become invasive, outcompeting native flora and reshaping ecosystems.



But what separates the cosmopolitan climbers from the homebodies? Are successful invaders simply taking advantage of empty niches abroad, or do they already have the right stuff at home?



An international team led by the <a href="https://www.uni-konstanz.de/en/" target="_blank" rel="noreferrer noopener">University of Konstanz</a> tested a deceptively simple idea: plant species that are thriving and expanding within their native habitats are the same ones most likely to take off overseas.



<h2 class="wp-block-heading" id="h-europe-s-role-in-global-spread">Europe’s role in global spread</h2>



Europe is one of the world’s main exporters of naturalized plants, making it an ideal proving ground. 



The researchers compiled decades of distribution records for 3,920 native <a href="https://www.earth.com/news/new-plant-species-has-flowers-with-tiny-horns-ovicula-biradiata/">plant species</a> across ten European regions (countries or subregions). They then reconstructed where each species occurred in an earlier period and where it occurred in a later one.



From those snapshots, they calculated an “occupancy-change” index - essentially, whether a species spread across more grid cells than you’d expect given where it started. 



Then they compared that native-range trajectory to how widely each species has naturalized globally, using a two-part model that accounts for both whether a species naturalizes at all and how many regions it colonizes if it does.



<h2 class="wp-block-heading" id="h-widespread-plants-spread-farther">Widespread plants spread farther</h2>



Two signals popped out across nearly all the regions. First, species that were already widespread in the early time period were more likely to show up as naturalized aliens elsewhere, and to do so in many regions.



Second, species that increased their footprint at home tended to be the very ones that spread abroad - nine of ten regions showed a positive link between “doing better at home” and “going farther away.”



In three regions - the Czech Republic, the Netherlands, and Switzerland - the effect was particularly strong for species that started out common and then expanded further. 



Together, the results suggest that the same biological advantages helping a plant proliferate in its native landscape - tolerance for varied <a href="https://www.earth.com/news/most-species-are-shifting-their-habitats-due-to-climate-change/">habitats</a>, strong dispersal, flexible life histories - also prime it for success overseas.



<h2 class="wp-block-heading" id="h-growth-at-home-signals-risk">Growth at home signals risk</h2>



A striking aspect of the study is that it didn’t rely only on static traits like range size. Many past analyses have shown that widely distributed species are more likely to naturalize.



Here, the “change” dimension mattered too: recent expansions at home carry predictive power, hinting that real-time monitoring of native-range dynamics can flag future invaders before they boom abroad.



The association with change was slightly weaker than the link with initial commonness. This was partly because some already-ubiquitous species had little room left to expand on paper. Even so, the pattern was robust across datasets assembled with different time windows and methods.



<h2 class="wp-block-heading" id="h-traits-of-global-plant-invaders">Traits of global plant invaders</h2>



So what do these winners look like? Broadly, they are big, versatile generalists that thrive in nutrient-rich, human-influenced habitats and compete well. Those traits help them occupy many places at home - and the same traits travel well.



The team also tested “woodiness” (tree or shrub vs. herb) as a coarse biological marker. Woodiness was often associated with increases in native occupancy. Long-lived plants can persist as conditions shift. 



However, woody species that did naturalize tended to do so in fewer regions than herbs. This is likely because they reproduce more slowly and are introduced less often.



The nuance underscores that there isn’t one recipe for success, but a cluster of advantages that often co-occur.



<h2 class="wp-block-heading" id="h-tracking-plants-can-guide-action">Tracking plants can guide action</h2>



If the plant species expanding in their home habitats are the ones most likely to naturalize - and sometimes become <a href="https://www.earth.com/news/growing-threat-of-invasive-species-requires-immediate-action/">invasive</a> - elsewhere, then tracking native-range dynamics becomes a powerful early-warning tool.



Agencies can prioritize surveillance and biosecurity around species currently on the rise in their native regions. This is especially true for species flourishing in disturbed, nutrient-enriched settings that mirror many human-dominated landscapes worldwide.



For exporters and importers, the findings argue for tighter scrutiny of horticultural and trade pathways that disproportionately move “successful” species.



The study also reframes a persistent debate: Are invaders opportunists exploiting empty ecological space, or are they simply robust competitors wherever they go?



The answer, at least for many European exporters, leans toward the latter. Species that are common and spreading don’t succeed abroad because foreign <a href="https://www.earth.com/news/how-environmental-stress-strengthens-ecosystems/">ecosystems</a> are uniquely vulnerable; they succeed because they are already built to win.



<h2 class="wp-block-heading" id="h-native-plant-booms-predict-global-spread">Native plant booms predict global spread</h2>



There’s an urgency to this work. Extinction risks are rising, but so is biotic homogenization - the gradual replacement of distinctive local floras with the same set of hardy generalists.



Watching which native plants are surging in their original habitats can help managers anticipate and mitigate that trend. Because policy resources are finite, insights like these can direct limited testing, regulation, and restoration budgets toward the species and pathways that matter most.



The bottom line is elegantly practical: If you want to know which plants will spread worldwide next, look first at which ones are spreading at home.



For Europe’s <a href="https://www.earth.com/news/plant-life-on-islands-loses-diversity-when-humans-arrive/">flora</a>, that simple lens predicted global outcomes with surprising consistency. It also offers a blueprint any region can adapt. 



The steps are straightforward: gather good time-series data on native occupancy, calculate change, and connect those trends to known naturalizations. Do that, and tomorrow’s invaders may not catch you by surprise.



The study is published in the journal <a href="https://www.nature.com/articles/s41467-025-63293-6" target="_blank" rel="noreferrer noopener">Nature</a>.



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Plants that dominate at home pose the greatest invasive threat abroad

Humans have moved plants around the planet for centuries, both...

We tend to explain the world by pointing to what things are, not what they’re interacting with. A new analysis argues that this bias has repeatedly steered science down blind alleys. 



The pattern shows up in classic missteps and in how people, even experts, reason today. The upshot: human cognition nudges theory toward inherent properties and away from the environment.



A team of psychology researchers from the <a href="https://www.ed.ac.uk/" target="_blank" rel="noreferrer noopener">University of Edinburgh</a> and <a href="https://www.nyu.edu/" target="_blank" rel="noreferrer noopener">New York University</a> mapped this recurring bias across history and in modern minds.



“Early scientific theories across multiple fields share a common pattern, in that they focus too much on built-in features and too little on interactions with surroundings,” said Zachary Horne, a lecturer in psychology at the University of Edinburgh and the paper’s lead author.



“This bias appears throughout the history of science, and its ‘fingerprints’ can even be seen among scientists today.”



<h2 class="wp-block-heading" id="h-the-bias-behind-early-theories"><a></a>The bias behind early theories</h2>



The authors argue that many foundational explanations leaned on assumed inner essences. Medieval accounts of motion, for example, claimed projectiles carried an internal “impetus” that kept them going until it ran out. Only later did Galileo and Newton replace this with dynamics grounded in external forces.



Study co-author Andrei Cimpian highlighted the cost of our default lens: “Some of the most significant achievements have come about as a result of scientific ingenuity," he said.



"But our <a href="https://www.earth.com/news/how-does-the-brain-process-experiences-over-time/">cognitive processes</a>, which favor explaining phenomena in terms of their inherent properties rather than external factors, seem to have historically slowed scientific discovery.” 



The researchers use the label “inherence bias” for this systematic tilt toward built-in features.



<h2 class="wp-block-heading" id="h-repeated-bias-in-science">Repeated bias in science</h2>



To test whether this pattern is widespread, the team surveyed historians of science in the U.S., Canada, and the U.K. Each historian listed major transitions: the initial explanation for an observation and the later, more accurate account. 



One example is the explanation of tides. Early observers described them simply as the “tidal motions of Earth’s large bodies of water.” 



Galileo suggested they were caused by the sloshing of oceans due to Earth’s motion, an idea researchers later categorized as an “inherent” explanation. 



Over time, however, this view was replaced by a more accurate understanding. Johannes Kepler and Isaac Newton demonstrated that tides are driven by the gravitational pull of the Moon - a model coded as “extrinsic” by the researchers.



Doctoral students trained in philosophy of science coded the responses as “inherent” or “extrinsic.” The vast majority of the nearly 80 initial explanations emphasized inherent properties; later explanations showed much less of that emphasis.



<h2 class="wp-block-heading" id="h-brownian-motion-as-a-case-study"><a></a>Brownian motion as a case study</h2>



Robert Brown’s 1827 observations offer a vivid example. Under the microscope, pollen grains suspended in water jittered. 



Early on, many biologists invoked a “vital force” inside living matter. But the pattern didn’t fit the data.



Decades later, the correct mechanism pointed outward: rapid, unseen <a href="https://www.earth.com/news/organic-molecules-found-throughout-the-universe-hint-that-life-began-in-deep-space/">molecules</a> in the surrounding water battering the grains. What looked like life’s essence was really interaction - now textbook “Brownian motion.”



<h2 class="wp-block-heading" id="h-today-s-scientists-fall-for-bias">Today’s scientists fall for bias</h2>



The authors then asked whether contemporary minds fall into the same groove. They ran experiments with practicing scientists, adult non-scientists, and children aged five to nine. Participants received real scientific observations they were unlikely to know and were asked to explain them.



Children, for instance, got: “why a hammer fell at the same speed as a feather on the Moon.” Adult non-scientists were asked to explain sediment appearing in distilled water after boiling. 



Scientists confronted harder puzzles, such as why some <a href="https://www.earth.com/news/astronomers-announce-evidence-suggesting-that-our-solar-system-has-nine-planets-again/">planets</a> lose mass over time, why a planet might have a given magnetosphere size, or why the tadpoles of the poisonous dart frog are not poisonous.



Across groups, first-pass theories leaned inward. When faced with sediment in boiled distilled water, one non-scientist reasoned that “heat caused the water to begin to turn into soil” - a throwback to ancient thinking.



Even experts showed the same pull, if in more technical language. On planetary mass loss, some cited “ejecta from volcanoes” and “transformation of matter on the planet into gas that dissipates away from the planet,” proposals that downplayed complex star-planet interactions.



<h2 class="wp-block-heading" id="h-fixing-science-starts-with-minds">Fixing science starts with minds</h2>



The researchers emphasized that these are not failures of scientists so much as features of human cognition. The world’s messiness tempts us to reach for what seems built in. That tendency can be productive at times, but it also detours progress when the real drivers are external forces and interactions.



“The path from initial explanatory intuitions to mature scientific understanding is rarely straightforward,” the authors wrote.



“This work suggests that one systematic source of detours may lie in our cognitive architecture itself - in the basic <a href="https://www.earth.com/news/how-the-human-brain-processes-visual-information/">information processing</a> constraints that guide how we first attempt to make sense of unfamiliar phenomena." 



"Understanding these constraints is crucial not just for advancing cognitive science, but also for improving how we train future generations of scientists.”



<h2 class="wp-block-heading" id="h-one-bias-shapes-science-s-path">One bias shapes science’s path</h2>



History’s wrong turns were not random. They followed a recognizable bias toward inherent properties. That same bias shows up today in children, laypeople, and trained researchers when they explain unfamiliar phenomena.



Recognizing the pull of “inherence bias” can help teachers and scientists nudge thinking outward - toward context, interaction, and the environment - so our next theories start closer to the truth.



 The study is published in the journal <a href="https://doi.org/10.1073/pnas.2424725122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Centuries of scientific errors reveal a hidden human bias

We tend to explain the world by pointing to what...

Elusive birds can be hard to protect, especially when they move under cover of darkness and lie low in thick desert grass by day. That’s the challenge with the night parrot, a small green-and-yellow species long considered near-mythical across Australia’s interior. 



A focused effort on <a href="https://en.wikipedia.org/wiki/Ngururrpa_Indigenous_Protected_Area" target="_blank" rel="noreferrer noopener">Ngururrpa Country</a> set out to answer three practical questions: where these parrots are living, what threatens them there, and what people can do now to keep them alive.



The approach was hands-on and methodical. Instead of waiting for chance sightings, the team paired local knowledge with tools that work while people sleep. 



The goal was simple: build a clear picture of the night parrot's daily needs and the pressures nibbling at its edges, find them, then save them.



<h2 class="wp-block-heading" id="h-in-search-of-the-night-parrot">In search of the night parrot</h2>



From 2020 to 2023, Indigenous rangers and scientists deployed rugged, weatherproof audio recorders across dozens of sites. 



Night parrots have distinctive calls, so detections on these devices acted like pins on a map. When recordings confirmed <a href="https://www.earth.com/news/parrots-that-learn-like-people-macaws-copy-without-being-taught/">parrots</a> at a location, camera traps followed to learn which predators showed up nearby. 



The team also collected predator scat to identify what those hunters had been eating, then added decades of satellite imagery to track how often fires rolled through the landscape.



Nick Leseberg, an ecologist at the <a href="https://www.uq.edu.au/" target="_blank" rel="noreferrer noopener">University of Queensland</a> and a co-author of the study, helped explain the soundscape these devices captured. 



“One of the night parrot’s diverse array of calls sounded like “didly dip, didly dip,” like a telephone, explains Leseberg. Another sounded like “dink dink,” resembling a bell."



<h2 class="wp-block-heading" id="h-what-they-heard-on-tape">What they heard on tape</h2>



Monitors detected night parrots at more than half of the surveyed sites, stretched across a wide slice of desert. 



That pattern points to a real population, not a stray bird passing through. Follow-up work located the birds’ daytime roosts inside dense, older clumps of spinifex grass. 



In this region the key plant is bull spinifex, also known as <a href="https://keys.lucidcentral.org/keys/v3/AusGrass/key/AusGrass/Media/Html/TRIODIA/TRILONC.HTML" target="_blank" rel="noreferrer noopener">Triodia longiceps</a>, which forms tough, dome-like shelters where a parrot can stay cool and hidden.



These shelters aren’t interchangeable. Younger, sparse spinifex doesn’t offer the same cover. Night parrots depend on mature, tightly packed clumps that take time to form. When those clumps are lost, there’s no quick substitute.



<h2 class="wp-block-heading" id="h-night-parrots-lost-their-shelters">Night parrots lost their shelters</h2>



The Great Sandy Desert sees <a href="https://www.earth.com/news/lightning-is-zapping-forests-harder-than-we-thought/">lightning strikes</a> and long, dry spells that can set off fast-moving fires. When blazes return too often, older spinifex doesn’t get the years it needs to grow into protective domes. 



The study found that country around roosts tends to burn on a cycle of several years, which is quick in plant terms and risks keeping the habitat stuck in a youthful, thinner stage.



There’s a practical fix within reach. Cooler, well-planned burns at the right times can create a patchwork of fuel breaks. 



That mosaic reduces the odds that one high-intensity wildfire will sweep across the sandplains and erase parrot shelter in one go.



<h2 class="wp-block-heading" id="h-predators-and-balance">Predators and balance</h2>



Cameras frequently recorded dingoes near parrot habitat. At face value, a wild dog near a small bird sounds like trouble. But scat analysis told a different story: cat remains showed up often. 



<a href="https://www.earth.com/news/feral-cats-kill-more-native-animals-than-expected/">Feral cats</a> hunt stealthily at night and can wipe out inexperienced fledglings. <a href="https://www.earth.com/news/australian-dingoes-evolved-from-dogs-in-east-asia/">Dingoes</a> appear to keep cat numbers in check, either by direct predation or by making key areas less comfortable for cats.



This balance matters. Push down dingo presence and cats may surge; keep dingoes on the scene and cat pressure may fall. 



For a species that nests and roosts on the ground, fewer cats near those roosts can mean more chicks making it through their earliest weeks.



<h2 class="wp-block-heading" id="h-numbers-don-t-lie">Numbers don't lie</h2>



Based on where birds were heard and how many called at once, the team estimates there could be about 50 night parrots in this protected area. 



For a species with very few confirmed individuals across Australia, that figure carries weight. It points to Ngururrpa Country as an important stronghold.



A stronghold isn’t guaranteed safety. A single rough fire season could knock back the habitat. Predator control programs that harm dingoes could open the door for more cats. 



Fresh disturbances - vehicle tracks, new weeds that change fire behavior, or grazing stock - could tilt the system in the wrong direction.



<h2 class="wp-block-heading" id="h-how-to-save-night-parrots">How to save night parrots</h2>



The recommendations fit the place. <a href="https://www.earth.com/news/experts-have-identified-the-key-driver-of-severe-wildfires-in-canada/">Fire management</a> should lean on the rangers’ deep local knowledge and use modern mapping to guide cooler-season burns. 



Those burns can cut fuel, set natural breaks, and lower the odds of summer wildfires racing across roosting country. 



Predator control should avoid harming dingoes, since dingoes may be doing important work by suppressing cats. 



Keeping the landscape relatively quiet - limiting disturbances and keeping grazing stock out - will help the vegetation hold its form.



The team also pointed to tools that can sharpen future counts and maps. Genetic methods, such as DNA recovered from feathers, could give more precise estimates.



Tiny tracking tags could show how far these parrots travel at night to feed and which patches matter most during the dry months.



<h2 class="wp-block-heading" id="h-what-have-we-learned">What have we learned?</h2>



This work shows what happens when Indigenous rangers and scientists align methods with the land. 



The night parrot needs old, dense spinifex for daytime cover, a fire rhythm that lets that grass mature, and a predator community where cats don’t run the show. 



With careful burns, smart predator management, and steady watchfulness, Ngururrpa Country can keep those needs on the table and give this shy bird a fair shot.



The full study was published in the journal <a href="https://www.publish.csiro.au/WR/WR24083" target="_blank" rel="noreferrer noopener">Wildlife Research</a>.



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Rare and beautiful bird, thought to be extinct, is rediscovered after 100 years of no sightings

Elusive birds can be hard to protect, especially when they...

Hundreds of human bones have been lifted from the River Thames over the past two centuries. A new analysis shows the pattern is not random and that many of these remains belong to people who lived long before Rome reached Britain.



The work uses modern dating to pull scattered finds into a single timeline. Results point strongly to late prehistory, when communities along the river were changing fast.



<h2 class="wp-block-heading" id="h-dating-human-bones-in-the-thames">Dating human bones in the Thames</h2>



Nichola Arthur, a curator at the Natural History Museum in London (<a href="https://www.nhm.ac.uk/" target="_blank" rel="noreferrer noopener">NHM</a>), led the research. Her team set out to anchor each bone in time, then compare the big picture across the entire river corridor.



The study reports 30 new radiocarbon dates and folds in previously reported results to create a stronger chronology. 



The clearest signal lands in the Bronze Age and Iron Age, two long periods that frame much of Britain’s later prehistory.



<h2 class="wp-block-heading" id="h-why-did-humans-end-up-in-the-thames">Why did humans end up in the Thames</h2>



“The big question for these human <a href="https://www.earth.com/news/organic-molecules-collagen-discovered-in-66-million-year-old-dinosaur-bones/">bones</a> is how they came to be in the river,” said Arthur. The combined dataset spans from roughly 4000 BC to AD 1800, with most dates falling between 2300 to 800 BC and 800 BC to AD 43. 



Many of the finds come from upstream zones rather than tidal reaches, which suggests local choices about where remains entered the water.



Earlier <a href="https://www.cambridge.org/core/journals/antiquity/article/human-skulls-from-the-river-thames-their-dating-and-significance/5CE79BBA69120FA0F0BB199755CDC0E8" target="_blank" rel="noreferrer noopener">research</a> on skulls from the Thames pointed to pattern, not accident. That study argued that dates and findspots show order rather than a simple sweep of the river.



Ideas have shifted over time, from stories of battles to scenarios that involve burial erosion or drownings. The new chronology trims those explanations by showing clear peaks in late prehistory.



<h2 class="wp-block-heading" id="h-why-watery-places-mattered">Why watery places mattered</h2>



Archaeologists sometimes use the term <a href="https://www.jstor.org/stable/4128304" target="_blank" rel="noreferrer noopener">votive deposition</a> for the deliberate placement of valued objects or human remains in rivers, lakes, or bogs. 



The late prehistoric Thames sits within a broader northwest European pattern that includes metalwork, animal remains, and sometimes human bones.



Bodies in wetlands are known from northern Europe as bog bodies, often with forensic signs that point to unusual deaths. 



Museum <a href="https://www.museumsilkeborg.dk/english" target="_blank" rel="noreferrer noopener">Silkeborg</a>’s resources on <a href="https://www.museumsilkeborg.dk/welcome-to-the-story-about-tollund-man" target="_blank" rel="noreferrer noopener">Tollund Man</a> show how waterlogged conditions can preserve skin and soft tissue. This helps investigators reconstruct life and death in the first millennium BC, illustrates the ritual use of wetlands in that era.



<h2 class="wp-block-heading" id="h-patterns-seen-in-the-thames-bones">Patterns seen in the Thames bones</h2>



The team used radiocarbon dating, a method that estimates age by measuring the decay of radioactive carbon in bone collagen. 



With careful lab preparation and calibration against tree ring records, the method can place these remains along a reliable time axis.



“We can now say with confidence that these don't appear to just be bones that have steadily accumulated in the river through time,” said Arthur. 



When the new dates were combined with earlier results, the distribution did not look like a slow, even drip of bones into the river. “



<h2 class="wp-block-heading" id="h-how-to-tell-ritual-from-accident">How to tell ritual from accident</h2>



Archaeologists weigh location, association with other finds, and traces left on bone. Patterns in <a href="https://www.earth.com/news/scientists-discover-a-33-foot-jurassic-giant-twice-as-big-as-its-cousin-xingxiulong/">skeletal</a> trauma can reveal blows, cuts, or projectiles, and weathering can show whether a body decomposed on land before entering the water.



Upstream concentrations and date peaks are clues, not verdicts. They restrict what is plausible, then encourage targeted tests that can separate ceremony from conflict or erosion.



Upstream zones are less likely to collect random debris from the estuary. Clusters there point to choices about where remains were placed or where people died.



Local topography, current lines, and fords could have shaped those choices. Communities may also have used particular bends or islands for repeated acts over generations.



<h2 class="wp-block-heading" id="h-thames-bones-tell-london-s-history">Thames bones tell London's history</h2>



If many of these remains entered the Thames as offerings, then the river was a stage for public acts tied to belief, law, or memory. That reframes the Thames as a social place long before it became a highway of empire and commerce.



If violence played a role, the river becomes a record of territorial stress and the risks that came with controlling access to water. Either way, the chronology lifts scattered <a href="https://www.earth.com/news/giant-long-necked-dinosaurs-struggled-with-fatal-bone-disease/">bones</a> into a coherent history.



“Exploring exactly how the Thames human remains might fit into these practices is one of the next exciting steps of the project,” said Arthur. Trauma analysis is underway, and it will test whether injuries match ritual killing, interpersonal conflict, or accidents.&nbsp;



Future work can add isotopes that track movement and diet, which will show whether the people came from local communities or from far afield. 



Careful mapping of findspots against ancient channels can also reveal whether deposition favored shallow crossings, eddies, or confluences.



Ceremony and conflict are not mutually exclusive. Communities can fold punishment, sacrifice, and display into single acts that leave similar traces in the water.



The new timeline narrows the field and raises sharper questions. That is progress, because good questions lead to tests that separate story from evidence.



The study is published in <a href="https://www.cambridge.org/core/journals/antiquity/article/abs/human-remains-from-the-river-thames-new-dating-evidence/EFB9C3236B3445A93CBC852BC252CDFA" target="_blank" rel="noreferrer noopener">Antiquity</a>.



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The River Thames has been used for human ritualistic sacrifices since the Bronze Age

Hundreds of human bones have been lifted from the River...

Humans often consider tool use a mark of intelligence. Yet many animals find creative ways to solve problems. A new study reveals how carrion crows - which seldom use tools in the wild - can learn to master them when trained.



Their performance suggests that with only small evolutionary changes, they might one day adopt tools as part of their natural behavior.



Researchers from the <a href="https://uni-tuebingen.de/en/" target="_blank" rel="noreferrer noopener">University of Tübingen</a> trained three carrion crows to handle sticks and retrieve food pellets placed inside a transparent Plexiglas box. 



<h2 class="wp-block-heading" id="h-from-beaks-to-borrowed-sticks">From beaks to borrowed sticks</h2>



The birds could not access the pellets with their beaks, so they had to explore with sticks. Success depended on careful manipulation: moving the pellet too quickly risked losing it from the platform.



"Tool use is very rare in the <a href="https://www.earth.com/news/crows-hold-grudges-for-up-to-17-years/">animal kingdom</a>, but relatively common in dexterous generalists such as primates, parrots, and corvids," said lead author Felix&nbsp;Moll.



Only two crow species - the New Caledonian and Hawaiian crow - use tools regularly. This experiment tested whether carrion crows could, with training, refine similar skills.



<h2 class="wp-block-heading" id="h-crows-master-deliberate-tool-actions">Crows master deliberate tool actions</h2>



The crows did more than just copy actions. They aligned sticks carefully with their beaks and guided food into reach.



"The crows first picked up the stick from a holder and adjusted it until they were grasping it so that it was precisely aligned with their beak. Then they used it to guide the pellet within reach," said Moll. They even returned the stick to the holder before eating.



Recordings showed early awkwardness: sticks shoved pellets back and forth with little success. Over time, movements became refined, efficient, and highly repeatable.



"By comparison, recordings of later training sessions showed extremely precise movement patterns. The movements of the stick varied little in standard situations; the crows determinedly guided the food pellet to one side of the box and fished it out," said co-author Julius Würzler.



<h2 class="wp-block-heading" id="h-practice-reveals-hidden-intelligence">Practice reveals hidden intelligence</h2>



The study used pose estimation to analyze thousands of trials. It found that the crows improved through reinforcement learning, a trial-and-error process where variability early on helped them discover effective strategies. 



This variability mirrors processes seen in human <a href="https://www.earth.com/news/dopamine-fuels-learning-in-young-songbirds/">motor learning</a>, where exploration refines skill. 



Such parallels remind us that intelligence does not always require a complex evolutionary leap. Sometimes, it is about applying existing flexibility to new challenges.



<h2 class="wp-block-heading" id="h-crows-show-flexible-problem-solving">Crows show flexible problem-solving</h2>



Each crow developed its own style - some preferred sliding pellets out to one side, while others adjusted depending on pellet position. 



These strategies were consistent and efficient, highlighting not just learned precision but also individuality in problem-solving. The presence of personal approaches suggests that tool use is not a rigid <a href="https://www.earth.com/news/crows-can-recognize-geometric-patterns-in-shapes/">behavior</a> but a dynamic process shaped by learning and constant feedback. 



Mistakes added another layer of insight: when a pellet slipped from control, the crows reacted within fractions of a second, adjusting stick movements to regain control. 



Such rapid corrections revealed continuous monitoring and flexibility, showing a level of awareness that goes beyond instinct and hinted at truly adaptive cognition.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/09/carrion-crows_precise-tool-use_infographic_UTubingen_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/09/carrion-crows_precise-tool-use_infographic_UTubingen_1s.webp" alt="Typical stick-tip trajectories during an early and late training session. The crow can’t reach the food reward without the stick-tool. Credit: University of Tübingen" class="wp-image-1986134"/></a><figcaption class="wp-element-caption">Typical stick-tip trajectories during an early and late training session. The crow can’t reach the food reward without the stick-tool. Click image to enlarge. Credit: University of Tübingen</figcaption></figure>



<h2 class="wp-block-heading" id="h-tool-grip-reveals-hidden-intelligence">Tool grip reveals hidden intelligence</h2>



Another striking behavior was how they adjusted stick orientation before use. Often, the stick was misaligned when pulled from the dispenser. 



The crows tossed and re-gripped it until alignment was perfect. This fine motor adjustment revealed an advanced capacity to prepare tools for effective use.



"Animal tool use is supported by a number of enabling factors: motivation, conceptual knowledge and advanced <a href="https://www.earth.com/news/ravens-develop-sophisticated-cognitive-skills-by-the-age-of-four-months/">cognitive skills</a>, as well as fine motor control," said co-author Andreas&nbsp;Nieder.



The carrion crows displayed all of these, suggesting their brains integrate the stick as part of their own body. Similar processes occur in primates, where neurons adapt to represent the working end of tools.



<h2 class="wp-block-heading" id="h-crows-hint-at-evolution">Crows hint at evolution</h2>



The findings show that non-habitual tool users can still reach high levels of dexterity. This supports the idea of “tooling,” where animals treat body and object as one system. 



Such results deepen our understanding of cognition in <a href="https://www.earth.com/news/crows-count-out-loud-just-like-toddlers/">birds</a> and may guide future research into neural mechanisms.



"If woodpeckers didn't already - with their highly-specialized long tongues - fish beetle larvae out of their burrows in dead wood, this nutritious source of protein might one day be exploited by carrion crows using tools," Moll adds. 



These experiments suggest that with only small evolutionary nudges, carrion crows could naturally evolve into regular tool users. 



The work also invites reflection on intelligence across species: when given the right opportunities, animals may reveal skills that once seemed uniquely human.



Click here to <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(25)01100-5" target="_blank" rel="noreferrer noopener">watch videos of carrion crows using precision tools...</a>



The study is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(25)01100-5" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Carrion crows can create, prepare, and use tools with great precision

Humans often consider tool use a mark of intelligence. Yet...

A recent analysis of the Sapphire Canyon mudstone core, drilled by NASA’s Perseverance rover in July 2024, adds new and convincing evidence to the ongoing search for life on Mars.



The study describes minerals and textures that - on Earth - are often linked to microbial activity. At the same time, the authors stress that some unknown, nonbiological chemistry could also explain the signals.



“This finding by Perseverance is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars,” said acting NASA Administrator Sean Duffy. 



“NASA’s commitment to conducting Gold Standard Science will continue as we pursue our goal of putting American boots on Mars’ rocky soil.”



The core was taken from a rock named "<a href="https://www.earth.com/news/perseverance-rover-finds-best-evidence-yet-life-on-mars-cheyava-falls-rock/">Chevaya Falls</a>" in Neretva Vallis, an ancient river channel about a quarter mile wide that once fed Jezero Crater’s lake. 



After drilling, <a href="https://www.earth.com/news/perseverance-rover-captures-a-surprise-dust-devil-while-taking-high-resolution-selfie-on-mars/">Perseverance</a> sealed the sample for possible return to Earth, where laboratory instruments can perform tests far beyond the rover’s onboard capabilities.



<h2 class="wp-block-heading" id="h-inside-the-martian-mudstone">Inside the Martian mudstone</h2>



Lead author Joel A. Hurowitz of <a href="https://www.stonybrook.edu/" target="_blank" rel="noreferrer noopener">Stony Brook University</a> (SBU) reports a fine-grained mudstone with circular reaction fronts informally called leopard spots, plus small nodules embedded in layered sediments.



Perseverance’s <a href="https://www.nasa.gov/centers-and-facilities/jpl/the-detective-aboard-nasas-perseverance-rover/" target="_blank" rel="noreferrer noopener">SHERLOC</a> and <a href="https://www.jpl.nasa.gov/news/heres-how-ai-is-changing-nasas-mars-rover-science/" target="_blank" rel="noreferrer noopener">PIXL</a> instruments mapped organic carbon with phosphate, iron, and sulfur arranged in distinct, repeating patterns.



Two minerals stand out: vivianite and greigite. Vivianite is an iron phosphate, while greigite is an iron sulfide associated with iron and sulfur cycling in oxygen-poor settings.



These features show up in rocks that settled from<a href="https://www.earth.com/news/wave-ripples-discovered-mars-surface-indicate-liquid-water-present-4-billion-years-ago/"> water</a>, not in lavas. The site on Mars lies along Bright Angel, a set of outcrops that preserve layers and veins consistent with slow changes after the mud was laid down.



Textures and chemistry point to low temperature reactions that reorganized elements already present in the mud. 



That detail matters because low temperatures fit environments that life can handle, while very hot conditions tend to erase delicate signals.



<h2 class="wp-block-heading" id="h-earth-microbes-leave-similar-traces">Earth microbes leave similar traces</h2>



On Earth, vivianite often forms where microbes reduce iron in water-rich sediments and trap phosphorus in blue-green nodules. 



Laboratory and field work document biologically mediated vivianite through extracellular electron transfer.



<a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/greigite" target="_blank" rel="noreferrer noopener">Greigite</a> frequently appears where sulfate reducing bacteria drive chemistry in anoxic muds. In controlled experiments, greigite was detected only in live biotic setups after months of incubation.



The Martian rock shows rims rich in vivianite surrounding small cores enriched in greigite. That bullseye pattern matches a sequence of electron transfer reactions seen in some Earth sediments.



None of this proves metabolism happened in Bright Angel mud, but it shows the chemistry is right for it. That is a subtle point, and it is the reason scientists keep the language cautious.



<h2 class="wp-block-heading" id="h-evidence-of-life-on-mars">Evidence of life on Mars</h2>



A potential biosignature is a feature that might have a biological origin but still needs more data to rule out nonbiological sources. 



NASA points mission teams and the public to the Confidence of Life Detection, or CoLD scale, which encourages staged claims and independent checks.



The CoLD mindset is simple in practice. First detect a signal, then exclude contamination, then tackle alternatives, and only then talk about life on Mars with high confidence.



The Bright Angel work sits early on that ladder. It clears several necessary steps but leaves demanding tests for the lab.



Organic compounds can also arrive by <a href="https://www.earth.com/news/what-meteorites-tell-us-about-their-birthplace-in-space/">meteorites</a> or form without biology. The authors note those routes and describe how future analyses could tell paths apart.



<h2 class="wp-block-heading" id="h-organic-signals-but-no-certainty">Organic signals, but no certainty</h2>



The Mars rover detected organic carbon in several targets within Bright Angel. Reaction fronts rimmed with vivianite surround cores richer in greigite, a pairing consistent with iron and sulfur cycling recorded in the paper.



Mineral veins include calcium sulfate, while the mudstone remains fine-grained and low in magnesium and manganese. There is no sign of intense heating that would reset the rock or scramble tiny textures.



The outcrop sits within layered sediments deposited by water flowing through Neretva Vallis. That channel spans roughly a quarter mile across, which implies sustained flow into Jezero’s ancient lake.



Low temperature context favors life-compatible chemistry, but it does not require life. Abiotic organics and <a href="https://www.earth.com/news/mineral-discovery-sheds-light-on-mars-fiery-past/">mineral</a> reactions can sometimes copy the same shapes and signals.



<h2 class="wp-block-heading" id="h-not-proof-but-potential-life-on-mars">Not proof, but potential life on Mars</h2>



“It’s not life itself,” said Nicky Fox, associate administrator for NASA’s Science Mission Directorate, stressing that this is a potential biosignature, not proof of life. The lead author echoed that caution.&nbsp;



“We cannot claim this is more than a potential biosignature,” said Hurowitz. Other officials also underscored the stakes and the limits.&nbsp;



“[But] this very well could be the clearest sign of life that we’ve ever found on Mars,” said Sean Duffy, acting NASA administrator. 



Caution is not hedging for its own sake. It is how science avoids false alarms when the question is this important.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/09/mars-life_olivine_leopard-spot_Cheyava-Falls_Perseverance-rover_NASA_1big.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/09/mars-life_olivine_leopard-spot_Cheyava-Falls_Perseverance-rover_NASA_1s.webp" alt="NASA’s Perseverance rover discovered leopard spots on a reddish rock nicknamed “Cheyava Falls” in Mars’ Jezero Crater in July 2024. Scientists think the spots may indicate that, billions of years ago, the chemical reactions in this rock could have supported microbial life; other explanations are being considered. Credit: NASA/JPL-Caltech/MSSS" class="wp-image-1985874"/></a><figcaption class="wp-element-caption">NASA’s Perseverance rover discovered leopard spots on a reddish rock nicknamed “Cheyava Falls” in Mars’ Jezero Crater in July 2024. Scientists think the spots may indicate that, billions of years ago, the chemical reactions in this rock could have supported microbial life; other explanations are being considered. Click image to enlarge. Credit: NASA/JPL-Caltech/MSSS</figcaption></figure>



<h2 class="wp-block-heading" id="h-implications-for-habitability">Implications for habitability</h2>



If the vivianite and greigite formed through microbe-like metabolisms, then <a href="https://www.earth.com/news/perseverance-rover-begins-steep-climb-up-martian-crater-rim-jezero-crater/">Bright Angel</a> captures a period when surface waters supported the same chemical strategies some cells use for energy today. 



That would extend Mars's habitability into a window when this part of Jezero was still wet.



If abiotic paths made the same pattern, the rock still records redox organization of iron, sulfur, and phosphorus in Martian mud. That is a window into how the planet cycles key elements without biology.



Either outcome matters for the bigger story. Mars did not just dry out, it changed its chemistry over time, and these samples let researchers track that change layer by layer.



The work also flags what to measure next. Isotopes, microtextures, and the exact structure of <a href="https://www.earth.com/news/carbon-atoms-in-your-body-took-a-400000-light-year-journey-through-space/">carbon</a> in the core can separate metabolic signatures from chemical lookalikes.



<h2 class="wp-block-heading" id="h-search-for-life-on-mars-moves-forward">Search for life on Mars moves forward</h2>



The authors lay out lab experiments and field analogs on Earth to test whether nonbiological reactions can reproduce these textures and mineral pairings. 



They also point to analyses that require the sample in a clean Earth lab, including isotope ratios that biology tends to skew.



Sample return planning will shape how fast those tests happen. Meanwhile, the rover can keep mapping where these features cluster and how they relate to other rock units nearby.



PIXL and SHERLOC have shown enough sensitivity to guide that search. The pairing of elemental maps and Raman detections gives a consistent picture that can be applied to other outcrops.



As new targets are logged, the CoLD framework will help communicate progress without getting ahead of the data. That is how a potential biosignature becomes a result people can trust.



<figure class="wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://youtu.be/ieJKWW8sp2A
</div><figcaption class="wp-element-caption">This animation depicts water disappearing over time in the Martian river valley Neretva Vallis, where NASA's Perseverance Mars takes the rock sample named “Sapphire Canyon” from a rock called “Cheyava Falls,” which was found in the “Bright Angel” formation. Credit: NASA/JPL-Caltech</figcaption></figure>



The study is published in the journal <a href="https://www.nature.com/articles/s41586-025-09413-0" target="_blank" rel="noreferrer noopener">Nature</a>.



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NASA announces "groundbreaking discovery" of life on Mars

A recent analysis of the Sapphire Canyon mudstone core, drilled...

Bees can turn awkward spaces into tidy hives. New research shows how they adapt their comb-building playbook when surfaces become irregular, using clever fixes that keep the hive functional.



The behavior resembles a distributed construction crew. It could even inspire better ways to print objects layer by layer.



A team of researchers at the <a href="https://www.colorado.edu/" target="_blank" rel="noreferrer noopener">University of Colora</a><a href="https://www.colorado.edu/">do Boulder</a> explored how bees coordinate to build usable honeycomb on imperfect foundations. Their experiments revealed robust, rule-like strategies that emerged from many tiny actions by individual bees.



<h2 class="wp-block-heading" id="h-beeswax-is-the-hive-s-concrete">Beeswax is the hive’s concrete</h2>



“Building a hive is a beautiful example of honeybees solving a problem collectively,” said Orit Peleg, an associate professor in CU Boulder’s Department of Computer Science. “Each bee has a little bit of wax, and knows where to deposit it, but we know very little about how they make these decisions.”



A colony builds on a precious budget. Bees spend warm months foraging nectar. Enzymes in saliva help convert that nectar into honey, which then dries and thickens inside cells. The economics are demanding: it takes roughly two million flower visits to make a pound of honey.



Then each worker eats about eight ounces of <a href="https://www.earth.com/news/natures-sweet-remedy-honey-is-a-microbial-marvel/">honey</a> to secrete a single ounce of wax. Wax is the concrete of the hive. The more efficiently bees use it, the more room they have for food and brood.



<h2 class="wp-block-heading" id="h-the-power-of-hexagons">The power of hexagons</h2>



Under ideal conditions, bees favor near-perfect <a href="https://www.earth.com/news/bees-and-wasps-use-the-same-nest-building-tricks-despite-independent-evolution/">hexagons</a>. The geometry is famous for efficiently packing space while using minimal material.



Natural nest sites, however, rarely offer perfect planes. Hollow trees, attic voids, and box frames introduce ripples, gaps, and curves.



On rough terrain, ideal cells become costly. Irregular sizes require more wax and reduce storage and brood efficiency. The hive still has to function - so the bees adjust.



<h2 class="wp-block-heading" id="h-bees-tackle-structural-challenges">Bees tackle structural challenges</h2>



The team set out to observe how those adjustments unfold. “We wanted to find the rules of decision-making in a distributed colony,” said Golnar Gharooni Fard, the study’s lead author.



They 3D-printed comb “foundations” with shallow hexagon guides in several sizes - smaller than normal, larger than normal, and near average.



These panels were placed into live hives near Boulder Creek, where forager bees mingled with returnees and the walls of hexagons began to rise.



After the bees built, the researchers scanned the new comb with X-ray microscopy to map its fine structure. The result was a catalog of on-the-fly building tactics that allowed colonies to bridge mismatches between the guided pattern and what their bodies and <a href="https://www.earth.com/news/when-bees-arrive-late-flowers-may-vanish/">behaviors</a> preferred.



<h2 class="wp-block-heading" id="h-bee-workarounds-keep-hives-thriving">Bee workarounds keep hives thriving</h2>



On small-cell guides, bees merged adjacent cells to recover usable volume. On larger guides, they tilted walls, layered cells, or introduced transitions to step down toward their favored size. Across patterns, the bees blended strategies. They didn’t abandon the site. They made it work.



“All those things happen in nature. If they're building honeycomb on a tree, and at some point they get to the end of the branch, the branch might not be super flat, and they need to figure that out,” said Fard.



The picture that emerges is not a top-down blueprint but a set of local rules distributed across many workers. Individuals add tiny wax deposits, sense geometry and neighbors, and adjust. The <a href="https://www.earth.com/news/science-is-giving-beekeepers-a-better-way-to-fight-colony-collapse/">colony</a>, in aggregate, solves the constraint.



The study stops short of pinning down the “why” behind each tactic. Some choices may balance strength, storage, and brood needs. Others may reflect limits of body size or heat flow. 



The authors want to probe the decision logic further - how bees switch tactics, how they partition labor, and how information spreads without a foreman.



<h2 class="wp-block-heading" id="h-beehive-wisdom-for-new-tech">Beehive wisdom for new tech</h2>



The implications extend beyond entomology. Honeycomb already inspires lightweight, stiff structures in aerospace and architecture. The new results add a dynamic twist: how to morph a repeating pattern across irregular boundaries without wasting material.



López Jiménez of CU Boulder’s Aerospace Engineering Sciences Department also sees lessons for additive manufacturing.



“The bees take turns, and they organize themselves, and we don't know how that happens,” he said. “Can we learn from how the bees organize labor or how they distribute themselves?”



If <a href="https://www.earth.com/news/walking-robots-can-step-right-off-the-3d-printer-powered-by-air/">3D printers</a> borrowed even a fraction of that adaptability - changing layer orientation or cell size on the fly to bridge defects - engineers could cut waste and improve reliability. The hive suggests a path: simple local rules scaled across many agents can yield resilient global structures.



<h2 class="wp-block-heading" id="h-architecture-born-from-evolution">Architecture born from evolution</h2>



Bees do not wait for perfect scaffolds. They treat irregular surfaces as puzzles and solve them with a toolkit of merges, tilts, and layers.



The work demonstrates how efficient architecture can emerge from countless small acts, each guided by limited information but tuned by evolution for thrift. That is good biology - and it might also be good engineering.



The study is published in the journal <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003253" target="_blank" rel="noreferrer noopener">PLOS Biology</a>.



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From hives to high-tech: How bees are transforming 3D printing

Bees can turn awkward spaces into tidy hives. New research...

Evolution is often framed as a slow process encoded into our DNA. Yet some scientists argue we may be witnessing a shift of a different kind - one driven not by biology but by culture. This idea challenges traditional views of how our species adapts and survives.



At the <a href="https://umaine.edu" target="_blank" rel="noreferrer noopener">University of Maine</a>, researchers Timothy M. Waring and Zachary T. Wood believe culture is overtaking genetics as the main force of human evolution. Their work suggests that humanity may be experiencing a transition rivaling some of the greatest shifts in evolutionary history.



"We find that culture solves problems much more rapidly than genetic evolution," said Waring. "This suggests our species is in the middle of a great evolutionary transition.”



<h2 class="wp-block-heading" id="h-evolution-s-new-driving-force">Evolution’s new driving force</h2>



From <a href="https://www.earth.com/news/early-neolithic-mountain-settlers-used-complex-farming-methods/">farming methods</a> to legal codes, cultural practices adapt far faster than biological evolution. These changes allow human groups to solve problems and adjust to environments in ways genetics cannot match. 



Waring and Wood argue that this transition is not new but is accelerating and could define humanity for millennia. “Cultural evolution eats genetic evolution for breakfast,” said Wood. “It’s not even close.”



Modern life illustrates this vividly. Eyeglasses, surgery, and fertility treatments intervene in challenges once governed by natural selection. Hospitals, schools, and governments have become cultural infrastructures that determine survival more than genetic traits.



“Ask yourself this: what matters more for your personal life outcomes, the genes you are born with, or the country where you live?” Waring said. 



“Today, your well-being is determined less and less by your personal biology and more and more by the cultural systems that surround you - your <a href="https://www.earth.com/news/community-sleep-health-predicts-success-among-children/">community</a>, your nation, your technologies. And the importance of culture tends to grow over the long term because culture accumulates adaptive solutions more rapidly.”



<h2 class="wp-block-heading" id="h-culture-moves-faster-than-dna">Culture moves faster than DNA</h2>



Culture is not just personal; it thrives on shared practices. Evidence from history and anthropology shows that group-level cultural adaptation has long shaped humanity, from the rise of agriculture to the creation of states. 



Health systems, sanitation, and education now contribute more to survival than individual intelligence or genetic luck.



The researchers suggest this reliance on shared systems means humans are evolving through culture to become more group-oriented and dependent. Our survival may hinge on cultural evolution and collective adaptation rather than individual genetic advantage.



<h2 class="wp-block-heading" id="h-groups-evolve-beyond-genetics">Groups evolve beyond genetics</h2>



Evolutionary history includes dramatic reorganizations of life, like single cells forming multicellular organisms or insects becoming highly cooperative <a href="https://www.earth.com/news/ant-colonies-behave-like-neural-networks-when-making-decisions/">colonies</a>. Waring and Wood argue humans could be undergoing a similar individuality transition.



“Cultural organization makes groups more cooperative and effective. And larger, more capable groups adapt - via cultural change - more rapidly,” said Waring. “It’s a mutually reinforcing system, and the data suggest it is accelerating.”



Societal complexity makes even genetic engineering possible, showing how culture controls biology itself. If this transition continues, future humans may resemble societal “super-organisms” shaped more by cultural systems than genetic evolution.



<h2 class="wp-block-heading" id="h-putting-culture-to-the-test">Putting culture to the test</h2>



The researchers stress that their theory is testable. They are developing mathematical models and long-term data collection to measure how quickly culture is overtaking <a href="https://www.earth.com/news/tens-of-thousands-of-hidden-dark-genes-discovered-in-humans/">genes</a>. Importantly, they caution against viewing cultural evolution as inevitable progress.



“We are not suggesting that some societies, like those with more wealth or better technology, are morally ‘better’ than others,” Wood said. “Evolution can create both good solutions and brutal outcomes. We believe this might help our whole species avoid the most brutal parts.”



At the University of Maine’s Applied Cultural Evolution Laboratory, Waring’s team continues to expand this work, exploring how cultural patterns can inform humanity’s future.



<h2 class="wp-block-heading" id="h-future-of-culture-and-evolution">Future of culture and evolution</h2>



The implications are vast. If cultural inheritance keeps dominating, human destiny may rest less on <a href="https://www.earth.com/news/ancient-dna-shows-what-really-spread-the-farming-revolution/">DNA</a> and more on the resilience of our communities, technologies, and institutions.



“If cultural inheritance continues to dominate, our fates as individuals, and the future of our species, may increasingly hinge on the strength and adaptability of our societies,” Waring noted.



In this view, evolution’s future may not be written in genes but in the shared systems and stories that bind us together, shaping our communities, guiding innovation, and influencing how societies survive, grow, and adapt.



The study is published in the journal <a href="https://academic.oup.com/bioscience/advance-article-abstract/doi/10.1093/biosci/biaf094/8230384?redirectedFrom=fulltext&amp;login=false" target="_blank" rel="noreferrer noopener">BioScience</a>.



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Culture is driving human evolution faster than our genes

Evolution is often framed as a slow process encoded into...

Every spring and fall, the clock shifts forward or backward one hour, throwing off sleep patterns and daily routines. A new analysis suggests that daylight saving time harms human health beyond the one or two days it normally takes for internal body clocks to adjust.



Researchers at <a href="https://med.stanford.edu/" target="_blank" rel="noreferrer noopener">Stanford Medicine</a> modeled how three policies - permanent standard time, permanent daylight saving time, and the twice-yearly switch - would shape <a href="https://www.earth.com/news/colors-of-sunset-and-sunrise-reset-our-circadian-rhythms/">circadian rhythms</a> and downstream health.



The study was led by graduate student Lara Weed in collaboration with Dr. Jamie Zeitzer, the study's senior author.



“We found that staying in standard time or staying in daylight saving time is definitely better than switching twice a year,” said Dr. Zeitzer.



<h2 class="wp-block-heading" id="h-why-daylight-saving-hurts-health">Why daylight saving hurts health</h2>



The team focused on circadian rhythm, the body’s nearly 24-hour clock that orchestrates sleep, <a href="https://www.earth.com/news/human-metabolism-has-evolved-to-become-energetically-unique/">metabolism</a>, immune function, and more. This clock is adjusted by light: exposure in the morning shifts it earlier, while light in the evening delays it.



“When you get light in the morning, it speeds up the circadian cycle. When you get light in the evening, it slows things down,” said Dr. Zeitzer. 



“You generally need more morning light and less evening light to keep well synchronized to a 24-hour day.”



The current policy forces a biannual lurch. That jolt has been tied to spikes in heart attacks and fatal crashes right after the spring jump. 



The new analysis looks beyond that acute window to the year-round misalignment that comes from toggling the clock.



<h2 class="wp-block-heading" id="h-standard-time-aligns-with-biology">Standard time aligns with biology</h2>



Using county-level sunrise and sunset times, the researchers translated predicted light exposure under each policy into “circadian burden,” the amount the body clock must shift to stay aligned with a 24-hour day.



On average, people would bear the least circadian burden under permanent standard time, which prioritizes morning light. Geography within a time zone matters, as does chronotype.



Early birds - about 15 percent of people - actually fare best under permanent daylight saving time because a bit more evening light stretches their naturally shorter internal day closer to 24 hours. 



For everyone else, the <a href="https://www.earth.com/news/keeping-standard-time-all-year-could-greatly-improve-our-health/">standard-time</a> bias toward morning light wins out.



<h2 class="wp-block-heading" id="h-new-data-for-a-heated-debate">New data for a heated debate</h2>



The debate, of course, is heated. “You have people who are passionate on both sides of this, and they have very different arguments,” noted Dr. Zeitzer.



Backers of permanent daylight saving time tout brighter evenings for energy, safety, and leisure, though a 1974 trial fizzled within a year as dark winter mornings drew public pushback. 



Medical and sleep organizations have rallied behind year-round standard time on theoretical grounds.



“It’s based on the theory that early morning light is better for our overall health,” Dr. Zeitzer said of the endorsements. “The problem is that it’s a theory without any data. And finally, we have data.”



<h2 class="wp-block-heading" id="h-clock-policy-shifts-disease-risk">Clock policy shifts disease risk</h2>



To link misalignment to real conditions, the team connected circadian burden with county-level prevalence of stroke, <a href="https://www.earth.com/news/obesity-is-driven-by-stress-and-inequality-not-just-diet-and-exercise/">obesity</a>, diabetes, depression, coronary heart disease, COPD, cancer, and arthritis.



The model suggests permanent standard time would trim obesity prevalence by 0.78 percent - about 2.6 million fewer people - and reduce stroke prevalence by 0.09 percent - roughly 300,000 fewer cases - each year across the United States.



Permanent daylight saving time would deliver smaller, but still notable, gains: a 0.51 percent drop in obesity (about 1.7 million people) and a 0.04 percent drop in stroke (around 220,000 cases). 



As expected, conditions with no clear circadian link, such as arthritis, did not budge in the model.



<h2 class="wp-block-heading" id="h-simulating-how-light-shapes-health">Simulating how light shapes health</h2>



The researchers assumed a fixed, <a href="https://www.earth.com/news/colors-of-sunset-and-sunrise-reset-our-circadian-rhythms/">circadian</a>-friendly pattern to isolate the time-policy effect: sleep from 10 p.m. to 7 a.m., sunlight before and after work and on weekends, and typical indoor lighting from 9 a.m. to 5 p.m. and after sunset.



That created a clean test bed for comparing policies. But real life is messier. Shift work, late-night screens, and indoor living pull people away from morning light and toward evening glow.



“The more light exposure you get at the wrong times, the weaker the circadian clock. All of these things that are downstream - for example, your immune system, your energy - don’t match up quite as well,” Zeitzer said.



<h2 class="wp-block-heading" id="h-testing-daylight-saving-time-health-impacts">Testing daylight saving time health impacts</h2>



Zeitzer stresses that the model almost certainly paints a best-case scenario for light hygiene. 



“People’s light habits are probably much worse than what we assume in the models,” Zeitzer said. “Even in California, where the weather is great, people spend less than five percent of their day outside.”



Weather, latitude, building design, <a href="https://www.earth.com/news/51-percent-of-the-world-relies-on-car-commutes-every-day/">commute</a> patterns, and behavior could all blunt or amplify the benefits of a given policy. 



The study also doesn’t weigh economic, crime, or social outcomes; those need their own evidence-driven analyses.



<h2 class="wp-block-heading" id="h-standard-time-is-the-best-fit">Standard time is the best fit</h2>



Even if lawmakers pick a time and stop switching, winter will still be dark and summer bright. Changing the policy only relabels the sun’s schedule. 



“That’s the sun and the position of Earth,” said Dr. Zeitzer. “We can’t do anything about that.”



If the goal is better health, the model’s message is straightforward. Permanent standard time aligns better with human biology for most people, and any permanent choice beats the twice-yearly flip. 



The path forward is a policy decision, but this time, it comes with data.



The research is published in the journal <a href="https://www.pnas.org/doi/10.1073/pnas.2508293122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Daylight saving time really does harm your health

Every spring and fall, the clock shifts forward or backward...

Today, the World Health Organization released new <a href="https://www.who.int/publications/i/item/9789240111608" target="_blank" rel="noreferrer noopener">guidelines</a> that add twice yearly lenacapavir as an additional <a href="https://www.hiv.gov/hiv-basics/hiv-prevention/using-hiv-medication-to-reduce-risk/pre-exposure-prophylaxis" target="_blank" rel="noreferrer noopener">pre-exposure prophylaxis</a> option and support simple rapid diagnostic test pathways as another HIV prevention tool.



These updates aim to keep progress in HIV prevention and treatment from stalling and to make care simpler in clinics and communities.



<a href="https://clinicalinfo.hiv.gov/en/drugs/lenacapavir/patient" target="_blank" rel="noreferrer noopener">Lenacapavir</a> is a long acting shot given twice a year that blocks HIV at a very early stage by targeting the virus’s protective shell, called the capsid. 



It joins daily pills, an injectable given every two months, and a vaginal ring, so people and programs can choose what fits.



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



By the end of 2024, an estimated 40.8 million people were living with HIV and about 1.3 million people acquired HIV that year, according to a WHO <a href="https://www.who.int/news/item/14-07-2025-who-recommends-injectable-lenacapavir-for-hiv-prevention" target="_blank" rel="noreferrer noopener">update</a>.&nbsp;



“We have the tools and the knowledge to end AIDS as a public health problem,” said <a href="https://www.iasociety.org/conferences/ias2023/about/organizing-committee/meg-doherty" target="_blank" rel="noreferrer noopener">Dr. Meg Doherty</a>, Director of <a href="https://www.who.int/teams/global-hiv-hepatitis-and-stis-programmes/hiv/overview" target="_blank" rel="noreferrer noopener">WHO</a>’s Department of Global HIV, Hepatitis and STI Programmes.



Fewer clinic visits can mean better adherence and more privacy for people who cannot manage daily pills or frequent pickups. Two visits a year can also help programs plan outreach and track follow up without overloading staff.



Importantly, this is an extra choice, not a replacement for other methods. Daily antiretroviral therapy (<a href="https://hivinfo.nih.gov/understanding-hiv/fact-sheets/hiv-treatment-basics" target="_blank" rel="noreferrer noopener">ART</a>) remains the standard for people living with <a href="https://www.earth.com/news/a-smarter-shot-scientists-explore-single-dose-vaccine-power/">HIV</a>, and oral and injectable PrEP still matter for prevention.



<h2 class="wp-block-heading" id="h-hiv-prevention-with-lenacapavir">HIV prevention with lenacapavir</h2>



The medicine is a capsid inhibitor, a class that binds to the protein shell that surrounds HIV and interferes with steps the virus needs to copy itself. 



By blocking multiple steps, the drug keeps the virus from establishing infection after exposure.



In a large <a href="https://www.nejm.org/doi/10.1056/NEJMoa2407001">trial</a> of cisgender women in South Africa and Uganda, no participants who received twice yearly lenacapavir acquired HIV during the analysis period. 



The lenacapavir group showed a lower incidence of infection than background rates and daily oral PrEP comparators.



Two clinic visits per year can fit school, work, or caregiving schedules that make frequent appointments hard. Sites can add safety checks, counseling, and STI screening to those visits so the prevention package stays comprehensive.



<h2 class="wp-block-heading" id="h-how-testing-will-work">How testing will work</h2>



The WHO guidance supports using simple rapid <a href="https://www.earth.com/news/dementia-is-going-undiagnosed-for-years-especially-in-young-patients/">diagnostic</a> test checks to start, continue, or pause long acting PrEP. 



This removes complex lab steps that have slowed access, and it enables delivery through pharmacies, clinics, and telehealth.



Home tests can play a role at key decision points, provided programs confirm results and link people to follow up. 



Clear instructions, quality kits, and documented training will keep mistakes rare and allow same day starts in many settings.



Programs will still need periodic clinic testing to confirm HIV negative status before each injection. They will also need systems to monitor missed visits and manage switches between options without gaps.



<h2 class="wp-block-heading" id="h-access-and-price-pressures">Access and price pressures</h2>



“We have seen services vanish overnight,” said <a href="https://www.unaids.org/en/aboutunaids/unaidsleadership/bios/winnie-byanyima" target="_blank" rel="noreferrer noopener">Winnie Byanyima</a>, Executive Director of <a href="https://www.unaids.org/en" target="_blank" rel="noreferrer noopener">UNAIDS</a>. The United States Food and Drug Administration has <a href="https://www.unaids.org/en/resources/presscentre/pressreleaseandstatementarchive/2025/june/20250618_lenacapavir" target="_blank" rel="noreferrer noopener">approved</a> lenacapavir for HIV prevention, and the company reported a U.S. list price of 28,218 dollars per person per year. 



That figure mirrors existing prevention medicines in the U.S., yet most countries will need prices closer to cost and reliable supply.



Lower prices, not for profit supply agreements, and faster registration can help scale access beyond pilot sites. Community based delivery will also matter so people who face stigma or criminalization can reach care safely.



<h2 class="wp-block-heading" id="h-next-steps-for-hiv-prevention">Next steps for HIV prevention</h2>



Countries will need to update national guidelines, train providers, and set up procurement and cold chain plans that match twice yearly delivery. 



Pharmacovigilance, data systems, and community feedback loops should be in place before scale up.



Lenacapavir should be offered within combination prevention that includes <a href="https://www.earth.com/news/millions-of-u-s-teens-lack-reliable-sex-education-in-the-classroom/">condoms</a>, testing, treatment as prevention, harm reduction, and options like cabotegravir and the dapivirine ring. 



Matching tools to local patterns of risk will make prevention fair and effective.



Equity should stay front and center so adolescents, sex workers, men who have sex with men, transgender people, and people who inject drugs can choose what works for them. 



Good policy can turn a promising tool into real protection, person by person.



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Historic breakthrough: WHO promotes new tool to curb HIV infection rates

Today, the World Health Organization released new guidelines that add...

Sad,Young,African,Woman,Touching,Back,Feeling,Backache,Morning,Discomfort

Most of us judge a night’s rest by how long we slept. However, studies confirm that the position in which you sleep also plays a significant role in human health - especially for your stomach and your heart.



Body position changes the path of acid in your esophagus, the way your lungs and diaphragm move, and even the balance of your nervous system. Small tweaks can pay off in comfort and in health.



One body of work that gets right to the point comes from Daniel Martin Simadibrata of the <a href="https://www.ui.ac.id/" target="_blank" rel="noreferrer noopener">University of Indonesia</a>. 



His team pulled together the best available evidence on sleeping position and reflux symptoms to see what actually helps.



They compared left side sleeping with the right side and with lying on your back. They also looked at whether nudging people to stay on their left side at night would reduce symptoms.



<h2 class="wp-block-heading" id="h-digestion-and-sleep-position">Digestion and sleep position</h2>



Gastroesophageal reflux disease (<a href="https://www.hopkinsmedicine.org/health/conditions-and-diseases/gastroesophageal-reflux-disease-gerd" target="_blank" rel="noreferrer noopener">GERD</a>) flares when stomach acid flows up into the esophagus. Sleeping on your left side, the left lateral decubitus <a href="https://www.researchgate.net/figure/Example-of-lateral-decubitus-position_fig1_335584367" target="_blank" rel="noreferrer noopener">position</a>, keeps the stomach below the esophagus, which makes reflux less likely.



A 2023 <a href="https://pubmed.ncbi.nlm.nih.gov/37969463/" target="_blank" rel="noreferrer noopener">meta-analysis</a> found left side sleeping cut acid exposure time by about 2 percentage points compared with the right side and back sleeping, and shortened acid clearance by roughly 75 to 82 seconds. Those changes were linked with better symptom scores at night.



“Current evidence suggests that sleeping on the left side could reduce nocturnal reflux and improve GERD-related quality of life,” stated Simadibrata. 



The analysis also reported no real advantage of laying on the right side over laying on the back for acid exposure or clearance.



Left side sleeping does not fix all reflux by itself. It reduces the odds that acid lingers where it should not.



<h2 class="wp-block-heading" id="h-wearing-devices-for-treatment">Wearing devices for treatment</h2>



Researchers also tested whether a gentle wearable can train position. In a double blind randomized <a href="https://pubmed.ncbi.nlm.nih.gov/35301135/" target="_blank" rel="noreferrer noopener">trial</a>, a small device vibrated to discourage right side sleeping and encouraged time on the left.



After two weeks, treatment success, defined as a 50 percent or greater drop in the nocturnal reflux score, occurred in 44 percent of the device group versus 24 percent of the sham group. 



The device group spent about 61 percent of the night on the left and only 2 percent on the right, and logged more reflux free nights.



These wearables do not add drug side effects. They simply steer you away from positions that make reflux worse.



<h2 class="wp-block-heading" id="h-side-sleep-positions-and-gut-health">Side sleep positions and gut health</h2>



On the right side, acid can collect near the junction where the esophagus meets the stomach. The meta-analysis showed longer acid exposure and slower clearance compared with the left, which explains the bump in symptoms.



<a href="https://www.earth.com/news/one-particular-sleep-stage-slow-wave-deep-is-most-important-for-preventing-dementia/">Sleeping</a> on your back, the supine position, did not beat the right side for reflux measures. If reflux wakes you, rolling to your left is a simple move that often helps.



Your gut microbiome is not silent during sleep. A 2022 <a href="https://pubmed.ncbi.nlm.nih.gov/36183306/" target="_blank" rel="noreferrer noopener">review</a> reported that shorter sleep in older adults was tied to more pro-inflammatory bacteria, while higher sleep quality tracked with more Verrucomicrobia and Lentisphaerae.



Causation is harder to prove, but a 2023 <a href="https://pubmed.ncbi.nlm.nih.gov/37754355/" target="_blank" rel="noreferrer noopener">study</a> using two sample <a href="https://www.nature.com/articles/s43586-021-00092-5" target="_blank" rel="noreferrer noopener">Mendelian randomization</a> found specific gut taxa that were causally linked with sleep traits, including sleep duration and chronotype. Some short chain fatty acid producers were associated with longer sleep.



These findings support the idea that better sleep habits can improve the mix of microbes that support gut health. They also show why sleep problems can ripple into digestion in ways you can measure.



<h2 class="wp-block-heading" id="h-peptic-ulcers-and-night-shifts">Peptic ulcers and night shifts</h2>



Shift work scrambles the circadian rhythm, and the stomach pays attention to that clock. 



A 2024 <a href="https://jhsss.sums.ac.ir/article_50452.html" target="_blank" rel="noreferrer noopener">review</a> found that five of eight included studies reported higher peptic ulcer risk in shift workers, with some studies showing more than double the prevalence versus day workers.



The authors also called for practical fixes at work, like steadier schedules and better meal timing, to reduce risk. That advice pairs well with personal sleep hygiene at home.



<h2 class="wp-block-heading" id="h-heart-health-and-sleep-positions">Heart health and sleep positions</h2>



For people with heart failure, the left side can feel uncomfortable because of pressure from an enlarged, pounding apex of the heart. 



A classic 2001 <a href="https://pubmed.ncbi.nlm.nih.gov/11401112/" target="_blank" rel="noreferrer noopener">study</a> found patients with heart failure spent about twice as much time on the right as on the left or back, and the right side normalized an off-balance autonomic nervous system.



Side sleeping also tends to lessen snoring. Back sleeping can worsen sleep disordered breathing, which stresses the heart over time.



If you live with a <a href="https://www.earth.com/news/easiest-habit-for-taking-care-of-your-heart-and-living-longer-walk-brisk-pace/">cardiac condition</a> or have an implanted device, ask your clinician which position works best for your symptoms. Personal advice beats one size fits all rules for the heart.



Many people without heart or lung disease do well on the left for reflux and on either side for breathing. If you have positional sleep apnea, your sleep doctor may coach you toward side <a href="https://www.earth.com/news/stress-hijacks-the-brain-disrupting-sleep-and-memory/">sleeping</a> more generally.



<h2 class="wp-block-heading" id="h-practical-ways-to-sleep-smarter">Practical ways to sleep smarter</h2>



If reflux wakes you, favor the left side and give dinner at least 3 hours before bedtime. Use a pillow setup that keeps your neck and hips supported so your spine stays neutral.



If heart failure makes the left side unpleasant, the right side is a reasonable choice. Keep the room dark, quiet, and cool, and stick to a steady schedule to help your body clock guide healthy digestion and cardiovascular rhythms.



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Sleep position directly impacts the health of your heart and stomach

Most of us judge a night’s rest by how long...

A new study pooled results from dozens of prior investigations to test whether small, everyday portions of processed meat, sugary drinks, and industrial trans fats are tied to common diseases. 



The analysis found that even modest daily intake is associated with higher risks of <a href="https://www.earth.com/news/scientists-identify-a-cellular-switch-mitochondria-that-could-reverse-type-2-diabetes/">type 2 diabetes</a>, colorectal cancer, and ischemic heart disease.



The estimates were not huge, but they were consistent, and they appeared even at low levels of intake such as a single hot dog or a 12 ounce soda. The researchers emphasized how risk rose with more consumption across the board.



Lead author <a href="https://www.researchgate.net/profile/Demewoz-Haile" target="_blank" rel="noreferrer noopener">Dr. Demewoz Haile</a> is a research scientist at the Institute for Health Metrics and Evaluation at the University of Washington in Seattle (<a href="https://www.healthdata.org/" target="_blank" rel="noreferrer noopener">IHME</a>).



<h2 class="wp-block-heading" id="h-processed-meat-and-daily-habits">Processed meat and daily habits</h2>



Experts who were asked to weigh in stressed how steady habits add up over time, and they pointed to the reliability of the pattern across many datasets.&nbsp;



“Habitual consumption of even small amounts of processed meat, sugary drinks, and trans fatty acids is linked to increased risk of developing type 2 diabetes, <a href="https://www.heart.org/en/health-topics/heart-attack/about-heart-attacks/silent-ischemia-and-ischemic-heart-disease" target="_blank" rel="noreferrer noopener">ischemic heart disease</a> and colorectal cancer,” said Dr. Haile.



Another nutrition scientist urged people to limit these foods for the long haul rather than chase perfection.&nbsp;



Current research, consistent with earlier findings, indicates that the best way to improve health is to avoid or keep intake of processed meat, sugar-sweetened beverages, and industrially produced trans fats as low as possible.



<h2 class="wp-block-heading" id="h-how-the-study-was-done">How the study was done</h2>



The team used a Burden of Proof approach, a type of meta-analysis that models how risk changes across the full range of intake while grading the consistency of the evidence. 



Most associations in this paper received two stars in that framework, which the authors describe as weak but still meaningful, with <a href="https://www.earth.com/news/processed-meat-can-cause-health-issues-even-in-tiny-amounts/">hot dogs</a> and other processed meat and ischemic heart disease receiving one star.



The dose response curves rose steadily, and they rose fastest at the low end of intake. That shape helps explain why small daily portions can move risk in population studies even if the per person effect looks modest.



<h2 class="wp-block-heading" id="h-what-counts-as-processed-meat">What counts as "processed meat"</h2>



Processed meat includes products preserved by smoking, curing, salt, or chemical preservatives, such as hot dogs, bacon, sausages, and deli meats. 



Processed meat is classified as carcinogenic to humans by the International Agency for Research on Cancer (<a href="https://www.iarc.who.int/wp-content/uploads/2018/11/Monographs-QA_Vol114.pdf" target="_blank" rel="noreferrer noopener">IARC</a>), with colorectal cancer as the main concern.



Sugar sweetened beverages cover regular sodas, fruit drinks that are not 100 percent juice, energy drinks, sports drinks, and sweetened coffees and teas. 



The 12 ounce can is a common serving, and that size showed measurable links with type 2 diabetes and ischemic heart disease in the analysis.



<h2 class="wp-block-heading" id="h-how-these-foods-may-harm-the-body">How these foods may harm the body</h2>



Processed meats often contain nitrite that can form <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/nitrosamine" target="_blank" rel="noreferrer noopener">nitrosamines</a>, compounds that can damage cells in the digestive tract. 



High heat cooking of meats can also produce polycyclic aromatic hydrocarbons and heterocyclic amines, which have been tied to tumor formation in prior lab and epidemiology work.



Sugar sweetened beverages deliver large amounts of rapidly absorbed sugar without much satiety, which drives excess calorie intake and strains insulin regulation over time. 



Industrial <a href="https://www.earth.com/news/junk-food-diet-triggers-lasting-changes-in-the-brain/">trans fatty</a> acids raise LDL cholesterol and lower HDL cholesterol, a pattern known to promote plaque buildup in arteries and increase cardiovascular risk.



<h2 class="wp-block-heading" id="h-what-the-evidence-shows">What the evidence shows</h2>



Observational data cannot prove causation, and dietary questionnaires can be imprecise, so caution is warranted when interpreting the size of the effects.&nbsp;



“When we look at the actual data there, it’s really remarkably consistent and remarkably strong, and even in the lower dose of consumption, we can still see an increased risk of disease,” said <a href="https://hsph.harvard.edu/profile/mingyang-song/" target="_blank" rel="noreferrer noopener">Dr. Mingyang Song</a>, associate professor of clinical epidemiology and nutrition at the Harvard T.H. Chan School of Public Health (<a href="https://hsph.harvard.edu/" target="_blank" rel="noreferrer noopener">HSPH</a>).



Others reminded readers to avoid fear and to keep diet in perspective alongside activity, stress, and access to care. 



The limitations of recall based diet tools and differences in study design leave some uncertainty, but none of that erases the pattern that higher intake tracks with higher disease risk.



<h2 class="wp-block-heading" id="h-processed-meat-and-human-health">Processed meat and human health</h2>



Global guidance suggests keeping free sugars to less than 10 percent of daily calories and ideally closer to 5 percent, and that directly targets sugar sweetened drinks, as laid out in a World Health Organization <a href="https://www.who.int/publications/i/item/9789241549028" target="_blank" rel="noreferrer noopener">guideline</a>. 



In the United States, the Dietary Guidelines also advise limiting added sugars to under 10 percent of calories across the life span, a point detailed in the federal <a href="https://health.gov/dietaryguidelines/2015/resources/2015-2020_dietary_guidelines.pdf" target="_blank" rel="noreferrer noopener">guidelines</a>.



Many countries are now removing industrial trans fats from the food supply, and the World Health Organization’s <a href="https://www.who.int/teams/nutrition-and-food-safety/replace-trans-fat" target="_blank" rel="noreferrer noopener">REPLACE</a> policy provides a template for doing it. 



That means fewer packaged foods will contain partially hydrogenated oils, but checking labels remains wise because trace amounts can still show up.



“The goal shouldn’t be perfection but rather a healthy and sensible dietary pattern that allows room for enjoyment,” said <a href="https://www.reading.ac.uk/food/our-staff/gunter-kuhnle" target="_blank" rel="noreferrer noopener">Dr. Gunter Kuhnle</a>, professor of nutrition and food science at the <a href="https://www.reading.ac.uk/" target="_blank" rel="noreferrer noopener">University of Reading</a> in the United Kingdom. 



Progress does not require a perfect diet or a strict set of rules. Small, steady changes, like swapping a daily soda for water or seltzer and choosing unprocessed proteins more often, can bring intake closer to those targets. 



The study is published in <a href="https://www.nature.com/articles/s41591-025-03775-8" target="_blank" rel="noreferrer noopener">Nature Medicine</a>.



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This could happen to your body if you eat just one hot dog every day

A new study pooled results from dozens of prior investigations...

What is Cadmium?

News coming your way