In a stark update on the deteriorating condition of our planet, an international assembly of climate experts has reported that the Earth’s vital signs have declined to levels never before witnessed in human history. This critical state threatens the very fabric of life on our planet.



<h2 class="wp-block-heading" id="h-unprecedented-scientific-consensus">Unprecedented scientific consensus</h2>



Led by William Ripple, a prominent figure from the Oregon State University <a href="https://www.forestry.oregonstate.edu/" target="_blank" rel="noreferrer noopener">College of Forestry</a>, and Christopher Wolf, formerly associated with OSU, a team comprising 12 scientists has delivered a grim prognosis on Earth&#8217;s vital signs in their paper published in <a href="https://academic.oup.com/bioscience/article-lookup/doi/10.1093/biosci/biad080" target="_blank" rel="noreferrer noopener">BioScience</a>. 



Titled &#8220;The 2023 State of the climate report: Entering uncharted territory,&#8221; the study underscores that a staggering 20 out of 35 planetary vital signs used as barometers for climate health have hit record extremes.



<h2 class="wp-block-heading" id="h-world-on-the-brink">World on the brink</h2>



&#8220;Without decisive steps to address the fundamental issue of humanity&#8217;s overconsumption of the Earth&#8217;s resources, we are navigating towards the potential disintegration of natural and socioeconomic systems,&#8221; Wolf stated, painting a picture of a future marred by intolerable heat, food scarcity, and water shortages.



The authors highlight alarming data from 2023, pointing out that numerous records related to climate and Earth&#8217;s vital signs have been shattered &#8220;by enormous margins.&#8221; This includes unprecedented ocean temperatures, drastic reductions in sea ice, and an extraordinary Canadian wildfire season contributing to record levels of carbon dioxide emissions.



<h2 class="wp-block-heading" id="h-echoes-of-past-warnings">Echoes of past warnings</h2>



This report is not the first of its kind. It follows a significant &#8220;<a href="https://www.earth.com/news/climate-change-has-pushed-earth-to-code-red/" target="_blank" rel="noreferrer noopener">World Scientists’ Warning of a Climate Emergency</a>&#8221; published four years ago, where Ripple, alongside other collaborators, received support from over 15,000 scientists from 161 countries. 



Despite these earlier calls to action, little progress has been made, with Ripple emphasizing, &#8220;Life on our planet is unmistakably under assault.&#8221;



<h2 class="wp-block-heading" id="h-alarming-climate-health-statistics">Alarming climate health statistics</h2>



The report lays bare several shocking statistics that outline why Earth&#8217;s vital signs are at an all-time low.



<ul class="wp-block-list">
<li><a href="https://www.earth.com/news/un-chief-fossil-fuel-era-must-end-for-humanitys-survival/" target="_blank" rel="noreferrer noopener">Fossil fuel</a> subsidies saw a staggering increase from $531 billion to over $1 trillion between 2021 and 2022, incentivizing harmful emissions. </li>



<li><a href="https://www.earth.com/news/wildfires-amplify-risks-for-socially-vulnerable-populations-in-western-states/" target="_blank" rel="noreferrer noopener">Wildfires</a> in Canada alone have already contributed more than 1 gigaton of carbon dioxide to the atmosphere in 2023, surpassing the nation&#8217;s total greenhouse gas emissions the previous year. </li>



<li>A concerning trend in global temperature rise, with 38 days already recorded where temperatures were more than <a href="https://www.earth.com/news/limiting-global-warming-to-1-5-degrees-celsius-would-save-billions-of-lives/" target="_blank" rel="noreferrer noopener">1.5 degrees Celsius</a> above pre-industrial levels. </li>



<li>July experienced the <a href="https://www.earth.com/news/july-was-earths-hottest-month-in-120000-years/" target="_blank" rel="noreferrer noopener">highest average</a> Earth surface temperature on record, likely the most extreme in the last 100,000 years.</li>
</ul>



Wolf expressed deep concern, stating, &#8220;As scientists, the sudden escalation in the frequency and intensity of climate-related disasters is deeply unsettling.&#8221;



The study cautions that these disasters&#8217; frequency and intensity might even be accelerating faster than temperature rises. The paper forecasts a dire future, where 3 to 6 billion people will find themselves in uninhabitable conditions by the end of this century.



<h2 class="wp-block-heading" id="h-earth-s-vital-signs-need-transformative-policies">Earth&#8217;s vital signs need transformative policies</h2>



The scientific community is advocating for policies that address &#8220;ecological overshoot,&#8221; a scenario where humanity&#8217;s demands exceed the Earth&#8217;s capacity, resulting in numerous environmental crises, including a decline in biodiversity.



They argue that solutions focusing solely on carbon or climate will fall short of repairing Earth&#8217;s vital signs unless the overarching pressures on global systems are alleviated. As Ripple puts it, the scientific community has a &#8220;moral duty&#8221; to guide humanity away from potential existential threats and lead action-driven dialogues.



<h2 class="wp-block-heading" id="h-steering-towards-a-just-sustainable-future">Steering towards a just, sustainable future</h2>



The paper calls for a comprehensive overhaul of global economic practices. The authors of the study urge a transition that foregrounds human well-being, curtails excessive consumption, and drastically reduces affluent populations&#8217; emissions.



Key policy recommendations to reverse the decline of Earth&#8217;s vital signs include:



<ul class="wp-block-list">
<li>Eliminating fossil fuel subsidies. </li>



<li>Encouraging shifts towards plant-based diets. </li>



<li>Amplifying efforts to protect global forest areas. </li>



<li>Establishing international treaties focused on eliminating coal and preventing new fossil fuel exploration.</li>
</ul>



The authors underscore the necessity for equity and social justice in all climate-related decisions. They clearly recognize the disproportionate impact of climate calamities on the world&#8217;s most impoverished populations, who have the smallest carbon footprints.



In a world where climate-related disasters are becoming the norm rather than the exception, this clarion call from the scientific community is more urgent than ever. It implores global leaders, decision-makers, and individuals alike to embark on a more sustainable path, with the understanding that the very future of life on Earth hinges on the actions humanity takes now.



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Life under siege: Earth’s vital signs reach an all-time low

Space can surprise even those who spend their lives studying it. People often think of our solar system as just a few planets and a bunch of empty space. 



Yet new observations suggest we have been living inside a hot, less dense region, and that there may even be a strange cosmic channel connecting us to distant stars.



After years of careful mapping, a new analysis reveals what appears to be a channel of hot, low-density plasma stretching out from our solar system toward distant constellations. Astronomers from the <a href="https://www.mpg.de/institutes" target="_blank" rel="noreferrer noopener">Max Planck Institute</a> recently confirmed it using data from the <a href="https://www.aanda.org/articles/aa/full_html/2021/03/aa39313-20/aa39313-20.html" target="_blank" rel="noreferrer noopener">eRosita instrument</a>. Dr. L. L. Sala, lead researcher, and colleagues shared these findings in a paper published in the journal <a href="https://www.aanda.org/articles/aa/full_html/2024/10/aa51045-24/aa51045-24.html" target="_blank" rel="noreferrer noopener">Astronomy &amp; Astrophysics</a>.



<h2 class="wp-block-heading" id="h-looking-beyond-the-familiar">Looking beyond the familiar</h2>



For a long time, scientists have known that our <a href="https://www.earth.com/news/international-space-station-observes-something-unknown-55-miles-above-earth/" target="_blank" rel="noreferrer noopener">solar system</a> sits within a peculiar region of space called the <a href="https://svs.gsfc.nasa.gov/11550" target="_blank" rel="noreferrer noopener">Local Hot Bubble</a>. 



This area, estimated to be <a href="https://www.annualreviews.org/content/journals/10.1146/annurev-astro-081710-102613" target="_blank" rel="noreferrer noopener">about 300 light years across</a>, formed as a result of powerful stellar explosions called supernovas. They heated the surrounding gas, producing a low-density, high-temperature environment. Traces of these distant events still linger as wispy distributions of hot plasma. “We find the temperature of the LHB exhibits a north-south dichotomy at high latitudes,” stated Dr. L. L. Sala, lead author of the study.



<h2 class="wp-block-heading" id="h-a-cosmic-x-ray-explorer">A cosmic X-ray explorer</h2>



To better understand this environment, scientists turned to eRosita. This X-ray observatory, launched as part of the <a href="https://heasarc.gsfc.nasa.gov/docs/srg/" target="_blank" rel="noreferrer noopener">Spectrum-Roentgen-Gamma mission</a>, scoured the sky to capture soft X-ray emissions. One of eRosita’s goals is to chart hot gas in space, learn about supernova remnants, and investigate the surroundings of <a href="https://www.earth.com/news/most-anticipated-comet-of-2024-returns-this-weekend-after-80000-years/" target="_blank" rel="noreferrer noopener">our neighborhood</a>.



By combining these results with older data from <a href="https://science.nasa.gov/mission/rosat/" target="_blank" rel="noreferrer noopener">ROSAT</a>, another X-ray survey, astronomers have pieced together a more detailed picture of our local region. They took on the challenging <a href="https://www.aanda.org/articles/aa/full_html/2013/10/aa22221-13/aa22221-13.html" target="_blank" rel="noreferrer noopener">task</a> of dividing the sky into thousands of bins, extracting subtle signals of warm gas, <a href="https://academic.oup.com/mnras/article/502/4/5779/6131844" target="_blank" rel="noreferrer noopener">dust cavities</a>, and interstellar structures. This painstaking approach helped isolate the faint glow of the surrounding plasma.



<h2 class="wp-block-heading" id="h-puzzling-cosmic-channel">Puzzling cosmic channel</h2>



What stands out is the detection of a channel, or “tunnel,” that appears to stretch toward the Centaurus constellation.



This feature seems to punch through the hot material, connecting our neighborhood to distant star systems.&nbsp;



Another such pathway appears to link toward the vicinity of Canis Major. Data hints these might be just one part of a larger, branching network of channels that run between star-forming regions and pockets of heated gas.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/milky-way_local-hot-bubble_eRosita_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/milky-way_local-hot-bubble_eRosita_1s.webp" alt="3D map of the Milky Way’s Local Hot Bubble (LHB) created from eROSITA data reveals a low-density region around the solar system, heated by ancient supernovas. The bubble shows temperature gradients and an interstellar “tunnel” toward Centaurus, likely formed by young stars’ winds. This bubble may connect to other superbubbles, shaping the Milky Way’s structure. The solar system entered the LHB a few million years ago, adding to our understanding of its cosmic neighborhood. Credit: Max Planck Institute" class="wp-image-1953925"/></a><figcaption class="wp-element-caption">3D map of the Milky Way’s Local Hot Bubble (LHB) created from eROSITA data reveals a low-density region around the solar system, heated by ancient supernovas. The bubble shows temperature gradients and an interstellar “tunnel” toward Centaurus, likely formed by young stars’ winds. This bubble may connect to other superbubbles, shaping the Milky Way’s structure. The solar system entered the LHB a few million years ago, adding to our understanding of its cosmic neighborhood. Credit: Max Planck Institute</figcaption></figure>



Each route may represent a kind of interstellar backroad, a path carved out by dynamic processes and influenced by the long-ago actions of exploding stars.



<h2 class="wp-block-heading" id="h-old-theories-on-cosmic-channels">Old theories on cosmic channels</h2>



Ideas about a network of hot, low-density channels are not new. 



Decades ago, some <a href="https://www.cambridge.org/core/services/aop-cambridge-core/content/view/381679E86154865FF68FE884DA62F1D4/S0074180900089348a.pdf/div-class-title-the-structure-of-the-interstellar-medium-div.pdf" target="_blank" rel="noreferrer noopener">researchers</a> speculated that the space around us could hold labyrinths of connected cavities. But there was never enough data to be sure. Instruments like eRosita have now provided that clarity. By showing tunnels and pockets filled with hot plasma, the findings confirm at least one piece of these older theories.



The presence of dust cavities packed with hot gas supports the notion that supernova events shaped a connected patchwork of interstellar matter.



<h2 class="wp-block-heading" id="h-not-just-empty-space">Not just empty space</h2>



It is tempting to think of <a href="https://www.earth.com/news/biggest-known-space-cloud-of-life-building-complex-chemicals-discovered/" target="_blank" rel="noreferrer noopener">space</a> as nothingness, but that is misleading. 



Even the void between stars contains various materials. The Local Hot Bubble is one example of how dramatic events can sculpt gas into unexpected forms.



Supernovas push out matter and energy that heat and churn the interstellar medium. Over millions of years, these actions create differences in density, temperature, and composition. 



The interplay of dust, plasma, radiation, and magnetic fields leads to an environment with far more complexity than a simple vacuum. The Max Planck Institute’s recent <a href="https://www.aanda.org/articles/aa/full_html/2024/10/aa51045-24/aa51045-24.html" target="_blank" rel="noreferrer noopener">study</a> argues that the average thermal pressure in this bubble is lower than expected, indicating that it might be open in some directions.



<h2 class="wp-block-heading" id="h-cosmic-channels-the-evidence">Cosmic channels: The evidence</h2>



While researchers have mapped parts of this hot region and uncovered these unusual passages, not every aspect is understood. 



Some star lines seem supported by a series of linked cavities. Other regions appear more blocked. The complexity of these patterns requires more sensitive data and further analysis. With time, better models may explain how these structures formed and how they continue to evolve.



Space’s calm appearance is deceiving. Over the past millions of years, our solar system drifted into the Local Hot Bubble. 



At roughly the same time, supernovas occurred nearby. The timing is not a coincidence. Those <a href="https://www.annualreviews.org/content/journals/10.1146/annurev-astro-081710-102613" target="_blank" rel="noreferrer noopener">ancient blasts</a> likely shaped the conditions we find today. The fact that our Sun now sits near the bubble’s center is simply chance, but it makes for an interesting perspective. It is as if we arrived late to a party, only to find a lingering aftermath of dramatic events that took place long before humans even existed.



<h2 class="wp-block-heading" id="h-peering-inside-a-hidden-structure">Peering inside a hidden structure</h2>



Continuing to explore these cosmic channels will require increasingly sensitive instruments. New X-ray missions, deeper surveys, and refined models of hot gas distribution will improve our understanding. Over time, astronomers hope to fill in more of this cosmic map and explain how these tunnels affect everything from local <a href="https://www.earth.com/news/rare-source-of-cosmic-rays-found-after-a-century-long-search/">cosmic rays</a> to dust flow patterns and stellar wind dynamics.



The discovery of these hidden routes and temperature differences offers a reminder that even our own cosmic backyard holds surprises. 



These channels challenge old assumptions and add complexity to the picture of what lies between our Sun and the nearest stars.&nbsp;



As technology advances and new methods improve, these discoveries are bound to raise even more questions. 



Every new piece of evidence will bring us closer to understanding both the <a href="https://www.earth.com/news/curvature-propulsion-warp-drive-krasnikov-tube-future-intergalactic-space-travel/" target="_blank" rel="noreferrer noopener">space</a> we inhabit today and the ancient events that shaped it.



What once seemed distant and unknowable may soon reveal connections that redefine our place in the cosmos.



The full study is published in the journal <a href="https://www.aanda.org/articles/aa/full_html/2024/10/aa51045-24/aa51045-24.html" target="_blank" rel="noreferrer noopener">Astronomy &amp; Astrophysics</a>.



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Astronomers discover an "interstellar tunnel" that connects our solar system to other stars

Space can surprise even those who spend their lives studying...

Cast,Of,Fossilized,Early,Ancient,Man,Skull.,Australopithecus,Afarensis,Is

The story of human evolution is not a simple ladder from early forms to more advanced ones. For decades, fossils shaped a picture of steady, linear progress - one form giving rise to another in a neat sequence.



But science often rewrites its narratives when new evidence appears. Now, remarkable finds in Ethiopia are challenging long-held assumptions and painting a richer, more intricate picture of our <a href="https://www.earth.com/news/big-males-small-females-a-window-into-prehistoric-power-struggles/">origins</a>.



Recent fossil discoveries in Ethiopia suggest that our evolutionary past was far more complex than a simple linear progression. 



Research led by UNLV anthropologist <a href="https://www.unlv.edu/people/brian-villmoare" target="_blank" rel="noreferrer noopener">Brian Villmoare</a>, in collaboration with the <a href="https://shesc.asu.edu/research/projects/ledi-geraru-research-project-0" target="_blank" rel="noreferrer noopener">Ledi-Geraru Research Project</a>, has revealed that Australopithecus and early and unidentified Homo species coexisted between 2.6 and 2.8 million years ago in the same part of Africa.



These findings challenge the traditional “march from ape to human” model and instead support the idea of a branching tree with multiple lineages.



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



Australopithecus walked the African landscape around 3 million years ago, bridging the gap between our <a href="https://www.earth.com/news/big-males-small-females-a-window-into-prehistoric-power-struggles/">ape-like ancestors</a> and modern humans. 



They stood upright, though shorter and smaller-brained than us, and their mix of traits - long arms for climbing, but pelvis and legs built for walking - shows how they lived in both trees and open grasslands. 



Fossils of species like Australopithecus afarensis, best known from the <a href="https://www.earth.com/news/lucy-could-barely-run-what-does-that-say-about-our-ancestors/">famous skeleton "Lucy,"</a> reveal that these early hominins were already experimenting with bipedalism while still relying on arboreal agility.



What makes Australopithecus so fascinating is the story their bones tell about adaptation. They didn’t use tools the way later hominins did, but they set the stage for it by freeing their hands once walking became the norm. 



Their teeth and jaws suggest <a href="https://www.earth.com/news/early-humans-had-surprising-diets-3-5-million-years-ago/">a varied diet</a>, probably fruits, roots, and tougher plants, helping them survive in shifting environments. 



<h2 class="wp-block-heading" id="h-australopithecus-lived-with-others">Australopithecus lived with others</h2>



At the <a href="https://shesc.asu.edu/research/projects/ledi-geraru-research-project-0" target="_blank" rel="noreferrer noopener">Ledi-Geraru site</a>, scientists found 13 teeth. Some belonged to early Homo, while others came from a previously unknown Australopithecus species.



The latter is different from the famous Australopithecus afarensis skeleton, known as “Lucy,” that disappeared from the fossil record around 2.95 million years ago. 



The research showed no evidence of Lucy’s kind aged any younger than 2.95 million years.



“This new research shows that the image many of us have in our minds of an ape to a Neanderthal to a modern human is not correct - evolution doesn’t work like that,” said <a href="https://www.asu.edu" target="_blank" rel="noreferrer noopener">ASU</a> paleoecologist Kaye Reed. 



“Here we have two hominin species that are together. <a href="https://www.earth.com/news/human-ancestor-paranthropus-robustus-walked-upright-2-million-years-ago/">Human evolution</a> is not linear - it's a bushy tree, there are life forms that go extinct.”



<h2 class="wp-block-heading" id="h-site-shows-oldest-homo-and-tools">Site shows oldest Homo and tools</h2>



Ledi-Geraru is already well known in paleoanthropology. It has produced the oldest known Homo jaw fossil, dated to 2.8 million years ago, and the earliest <a href="https://www.earth.com/news/first-tools-ever-made-on-earth-hominins-3-million-years-ago-cradle-of-humankind/">Oldowan stone tools</a>. 



The site’s sediments, which are rich in <a href="https://www.earth.com/news/prehistoric-homo-sapiens-stone-tools-preserved-volcanic-ash-grotta-di-castelcivita/">volcanic ash</a>, allow precise dating.



Crystals in the ash, called feldspars, are key for determining the ages of fossils, as they can be dated from volcanic eruptions above and below the fossil layers. 



This geological context also provides clues about the environment in which these species lived.



<h2 class="wp-block-heading" id="h-australopithecus-territory-had-rivers">Australopithecus territory had rivers</h2>



Two to three million years ago, the Ledi-Geraru area was a dynamic landscape of rivers, vegetation, and shallow lakes that expanded and shrank over time. 



This is a stark contrast to today’s faulted badlands. 



Geological evidence indicates that the region preserved an interpretable record for the period from 2.3 to 2.95 million years ago - a crucial time in terms of <a href="https://www.earth.com/news/early-humans-ate-tough-plants-and-changed-the-world-forever/">human evolution</a>.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/08/new-hominin-species_fossil-teeth_LGRP_credit-Nature_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/08/new-hominin-species_fossil-teeth_LGRP_credit-Nature_1s.webp" alt="New hominin species fossil teeth from the LGRP. Credit: Nature" class="wp-image-1982136"/></a><figcaption class="wp-element-caption">New hominin species fossil teeth from the LGRP. Click image to enlarge. Credit: Nature</figcaption></figure>



<h2 class="wp-block-heading" id="h-multiple-lineages-multiple-niches">Multiple lineages, multiple niches</h2>



The study concluded that before 2.5 million years ago, eastern Africa may have had as many as four hominin lineages: early Homo, Australopithecus garhi, the newly discovered Ledi-Geraru Australopithecus, and potentially others in nearby regions.



“We used to think of human evolution as fairly linear, with a steady march from an ape-like ancestor to modern Homo sapiens," Villmoare said. 



Instead, humans branched out multiple times into different niches.



"Our pattern of evolution is not particularly unusual, and what has happened to humans has happened to every other tree of life.” 



<h2 class="wp-block-heading" id="h-tooth-enamel-holds-hidden-answers">Tooth enamel holds hidden answers</h2>



Detailed analysis of the teeth showed differences from known Australopithecus and Homo specimens. 



These distinctions suggest the Ledi-Geraru Australopithecus was neither a late-surviving A. afarensis nor A. garhi, but rather a previously unknown species. 



However, the team has not yet named it, as more fossils are needed for a full classification.



Researchers are now studying the <a href="https://www.earth.com/news/tooth-enamel-analysis-suggests-early-eurasians-were-multiple-species-paranthropus-robustus/">tooth enamel</a> to understand diet and possible interactions between early Homo and this Australopithecus species. 



<h2 class="wp-block-heading" id="h-more-study-is-needed">More study is needed</h2>



Key questions remain: Did they compete for food or share resources? How often did they encounter each other? Who were their ancestors?



“Whenever you have an exciting discovery, if you’re a paleontologist, you always know that you need more information,” Reed explained. “You need more fossils.”



“That’s why it’s an important field to train people in - and for people to go out and find their own sites and explore places where we haven’t yet found fossils.”



More finds could reveal not just how these species lived but also why some survived while others vanished.



The study is published in the journal <a href="https://www.nature.com/articles/s41586-025-09390-4" target="_blank" rel="noreferrer noopener">Nature</a>.



Image Credit: Kaye Reed, <a href="https://www.asu.edu/" target="_blank" rel="noreferrer noopener">Arizona State University</a>.



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New early Homo species discovered that challenges 'ape-to-human' evolution theory

The story of human evolution is not a simple ladder...

For many people, mornings don’t really begin until the first sip of coffee. That drink doesn’t just wake the body - it flips a switch in the mind. Researchers at Bielefeld University and the University of Warwick wanted to know why coffee feels so uplifting in the morning compared with the afternoon.



The team followed young adults in Germany for several weeks. Each person tracked their mood and reported whether they had consumed caffeine in the last 90 minutes. 



The results were clear. <a href="https://www.earth.com/news/drinking-coffee-may-reduce-frailty-in-aging-adults/">Coffee</a> and other caffeinated drinks boosted happiness and enthusiasm. The effect was strongest within two and a half hours of waking. Later in the day, the effect weakened.



<h2 class="wp-block-heading" id="h-morning-coffee-resets-our-mood">Morning coffee resets our mood</h2>



<a href="https://www.earth.com/news/coffee-helps-bacteria-resist-antibiotics-in-your-gut/">Caffeine</a> didn’t only improve positive feelings. It also reduced negative ones like sadness and being upset. But that change was smaller and less reliable. Unlike the morning lift in happiness, this effect didn’t depend on the time of day.



The difference may lie in how caffeine works. It blocks adenosine receptors in the brain. This lifts energy and increases dopamine activity. 



Dopamine is tied to alertness and mood. Together, these changes explain why the morning cup feels like such a mental reset.



<h2 class="wp-block-heading" id="h-do-people-react-differently">Do people react differently?</h2>



The team expected to see differences based on mental health, anxiety, or caffeine habits. But they didn’t. 



"We were somewhat surprised to find no differences between individuals with varying levels of caffeine consumption or differing degrees of depressive symptoms, anxiety, or sleep problems," noted Justin Hachenberger from <a href="https://www.uni-bielefeld.de" target="_blank" rel="noreferrer noopener">Bielefeld University</a>.



"The links between caffeine intake and positive or negative emotions were fairly consistent across all groups."



This result suggests that caffeine’s emotional effects are widely shared. People who react badly to caffeine may avoid it, so they were not strongly represented in the study. 



<h2 class="wp-block-heading" id="h-the-withdrawal-question">The withdrawal question</h2>



Scientists also debated whether the morning boost is real or simply relief from overnight withdrawal. 



"<a href="https://www.earth.com/news/coffee-may-help-you-live-longer-if-you-drink-it-this-way/">Caffeine</a> works by blocking adenosine receptors, which can increase dopamine activity in key brain regions - an effect that studies have linked to improved mood and greater alertness," explained Professor Anu Realo from the <a href="https://warwick.ac.uk" target="_blank" rel="noreferrer noopener">University of Warwick</a>.



"Even people with moderate caffeine consumption can experience mild withdrawal symptoms that disappear with the first cup of coffee or tea in the morning." 



In other words, coffee may feel good not only because of brain chemistry but also because it takes away the drag of going without caffeine during sleep.



<h2 class="wp-block-heading" id="h-mood-changes-depend-on-coffee-use">Mood changes depend on coffee use</h2>



The research showed that tiredness and social setting also change how caffeine feels. When people were more tired than usual, <a href="https://www.earth.com/news/can-caffeine-slow-down-aging-yeast-may-hold-the-answer/">caffeine</a> gave them a bigger mood boost. 



When people were around others, the effect weakened. Social interactions may have already shaped mood, leaving caffeine less noticeable.



Negative feelings like worry didn’t shift much. Researchers think these emotions are tied to long-term stress or life events. That makes them harder to change with one drink. Positive emotions, on the other hand, respond more quickly to stimulation.



<h2 class="wp-block-heading" id="h-global-link-between-coffee-and-mood">Global link between coffee and mood </h2>



"Around 80 percent of adults worldwide consume caffeinated beverages, and the use of such stimulating substances dates far back in human history," said Professor Sakari Lemola from Bielefeld University, the study’s senior author. 



"Even wild animals consume caffeine; bees and bumblebees prefer nectar from plants that contain caffeine."



Coffee is more than a drink. It is part of daily routines across cultures. Yet researchers warn against drinking too much. High doses can disturb sleep and increase dependence. Over time, stopping suddenly can trigger headaches, irritability, and fatigue.



<h2 class="wp-block-heading" id="h-mood-boost-from-morning-coffee">Mood boost from morning coffee</h2>



The study shows caffeine works best early in the day. It makes people feel happier, more awake, and more enthusiastic. But the effect doesn’t grow stronger with each cup. It fades as the day goes on.



For most people, moderation is the key. That first cup can brighten the morning, but too much can backfire. 



Coffee may not solve deeper worries or stress, but it can lift the mood enough to start the day with energy.



The study is published in the journal <a href="https://www.nature.com/articles/s41598-025-14317-0" target="_blank" rel="noreferrer noopener">Scientific Reports</a>.



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Mood boost: How coffee makes us happier in the morning

For many people, mornings don’t really begin until the first...

In 2024, the world’s climate continued to break records, with greenhouse gas concentrations and global temperatures reaching unprecedented highs.



The oceans absorbed more heat than ever before. Sea levels climbed to their highest point on record, and glaciers shed more ice than in any prior year.



This year’s State of the Climate report, published by the <a href="https://www.ametsoc.org/ams/">American Meteorological Society</a>, brought together 589 scientists from 58 countries. 



The experts used data from satellites, weather stations, ocean buoys, and ice-core records. For decades, this report has been the go-to snapshot of Earth’s climate - tracking key changes and <a href="https://www.earth.com/news/2024-confirmed-as-earths-hottest-year-in-recorded-history/">extreme events</a> across the globe.



<h2 class="wp-block-heading" id="h-greenhouse-gases-hit-highest-levels">Greenhouse gases hit highest levels</h2>



Carbon dioxide, methane, and nitrous oxide all set new records in 2024. Average CO2 levels reached 422.8 parts per million, up 52% from pre-industrial times. The jump from 2023 matched the fastest increase seen in the past 60 years.



Fossil fuel burning and agriculture remain the biggest sources. Rising greenhouse gases are locking in more heat, driving stronger feedback loops like higher water vapor in the <a href="https://www.earth.com/news/climate-extremes-in-2024-what-have-we-learned/">atmosphere</a> and changes in how land stores carbon.



<h2 class="wp-block-heading" id="h-heat-breaks-climate-records-again">Heat breaks climate records again</h2>



For the second year in a row, the planet broke its surface temperature record. Readings were up to 0.72°C (1.30°F) above the 1991-2020 average. 



A strong El Niño that began in mid-2023 and ended in spring 2024 helped push temperatures higher.



Heat extremes weren’t limited to the tropics. Europe, Asia, and South America saw their hottest years yet. Heatwaves lasted longer and struck at times of year when they used to be rare.



<h2 class="wp-block-heading" id="h-extreme-rain-and-drought">Extreme rain and drought</h2>



Warmer air holds more moisture, and in 2024 it showed. The atmosphere carried record levels of water vapor. One in five areas on Earth hit all-time highs, double the share from 2023.



Heavy rain events set records too. Dubai saw 250 mm in one day - three times its yearly average. While some places were drowning, others faced persistent droughts and extreme heat.



<h2 class="wp-block-heading" id="h-ocean-heating-breaks-climate-records">Ocean heating breaks climate records</h2>



From January through June, sea surface temperatures refused to budge from record-breaking highs. 



The global average edged past the 2023 mark by 0.06°C (0.11°F) - a small number on paper, but significant in climate terms. A potent El Niño, layered on top of decades of steady warming, drove the surge.



Vast stretches of ocean endured marine heatwaves - bleaching coral reefs, pushing fish into new territories, and unsettling entire food webs. On average, the seas sweltered through 100 heatwave days in 2024, while cold spells were rare - just nine days across the year.



<h2 class="wp-block-heading" id="h-sea-levels-keep-rising">Sea levels keep rising</h2>



Oceans absorb over 90% of excess heat from greenhouse gases. In 2024, heat content down to 2,000 meters (6,562 feet) reached its highest ever. 



Global sea level hit a new high for the 13th year straight - over 10 centimeters (3.94 inches) above 1993 levels.



Warmer water expands, and melting ice from Greenland, Antarctica, and glaciers adds more volume. The result is higher flood risks and saltwater intrusion into freshwater supplies.



<h2 class="wp-block-heading" id="h-record-heat-at-the-poles">Record heat at the poles</h2>



The Arctic experienced its second-warmest year on record, with autumn setting an all-time high for temperatures.



In August, parts of the North American Arctic endured record high temperatures, and Norway topped 30°C (86°F) in September for the first time that late in the year.



Antarctica’s sea ice stayed far below average. Minimum and maximum extents were the second lowest ever recorded, continuing a run of poor ice years since 2016.



For the second consecutive year, all 58 reference glaciers lost ice in 2024. It was the worst year for glacier loss in the 55-year record. Venezuela lost its last glacier. In Colombia, the Conejeras Glacier vanished completely.



These losses threaten water supplies for farming, hydropower, and drinking water in many mountain regions.



<h2 class="wp-block-heading" id="h-storms-bring-destruction">Storms bring destruction</h2>



There were 82 named tropical cyclones in 2024, fewer than average but still deadly. Hurricane Helene flooded parts of the U.S., killing more than 200 people. 



Hurricane Milton hit Florida less than two weeks later - setting a state record for the shortest gap between two major hurricanes.



In Asia, Super Typhoon Yagi tore through China and Vietnam, leaving more than 800 dead. Many storms intensified unusually quickly, fueled by warmer <a href="https://www.earth.com/news/astonishing-global-heat-in-january-2025-defied-climate-expectations/">ocean</a> waters.



<h2 class="wp-block-heading" id="h-our-changing-climate-reality">Our changing climate reality</h2>



“The State of the Climate report is an annual scientific landmark,” said American Meteorological Society President David J. Stensrud. 



"It is a truly global effort, in which hundreds of researchers from universities, government agencies, and more come together to provide a careful, rigorously peer-reviewed report on our planet’s climate."



"High-quality observations and findings from all over the world are incorporated, underscoring the vital importance of observations to monitor, and climate science to understand, our <a href="https://www.earth.com/news/earth-is-just-three-years-away-from-dangerous-carbon-milestone/">environment</a>." 



According to Stensrud, the results affirm the reality of our changing climate, as global temperatures continue to reach record highs.



The research is published in the <a href="https://www.ametsoc.org/ams/publications/bulletin-of-the-american-meteorological-society-bams/state-of-the-climate/" target="_blank" rel="noreferrer noopener">Bulletin of the American Meteorological Society</a>.



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State of the Climate 2024: Record heat and rising seas

In 2024, the world’s climate continued to break records, with...

If you live around Naples, you know the ground breathes. Streets crack, the harbor silts up, steam curls from the earth, and swarms of small quakes rattle windows. All that action comes from Campi Flegrei, a wide “supervolcano” caldera that last erupted in 1538.



For years, many scientists have read these signals as classic signs of magma on the move. But two recent studies - one in March 2023 and another in May 2025 - have reshaped the picture.



Together, they tell a story that is both sobering and surprisingly hopeful: Campi Flegrei is still dangerous, but some of its most disruptive <a href="https://www.earth.com/news/volcano-eruptions-alerts-shear-wave-signals-discovered-that-could-transform-early-warning-systems/">behavior may be managed</a>.



<h2 class="wp-block-heading" id="h-studying-campi-flegrei-in-2023">Studying Campi Flegrei in 2023</h2>



The <a href="https://pubs.geoscienceworld.org/gsa/geology/article/51/4/397/620796/Discriminating-carbon-dioxide-sources-during" target="_blank" rel="noreferrer noopener">2023 paper</a> focused on carbon dioxide (CO₂), a gas that volcanoes <a href="https://www.earth.com/news/volcanic-cooling-not-warming-caused-a-major-mass-extinction/">release in large amounts</a>. CO₂ matters because it often increases when magma rises and starts to degas, which can precede eruptions. 



At the Campi Flegrei caldera, CO₂ measurements at the <a href="https://www.researchgate.net/figure/a-Geologic-map-of-the-Solfatara-Pisciarelli-area-from-this-study-UTM-projection_fig2_351100327" target="_blank" rel="noreferrer noopener">Solfatara-Pisciarelli zone</a> rose during the current unrest (which began in 2005), reaching roughly 4,000-5,000 tons per day - among the highest volcanic CO₂ fluxes on Earth. 



If one looked only at that trend, one might conclude that magma was moving upward and a countdown to an eruption had begun.



The authors investigated further. They examined gases such as nitrogen and helium alongside CO₂ and compared the real data to what their models predicted if magma degassing were the only driver. 



The numbers did not line up. 



Beginning in 2005, the gas ratios drifted away from the “<a href="https://www.earth.com/news/the-sun-affects-magma-formation-deep-within-the-earth/">pure magma</a>” pattern, matching two surface indicators: hydrothermal temperatures and the steady ground uplift known locally as bradyseism.



<h2 class="wp-block-heading" id="h-where-was-the-gas-coming-from">Where was the gas coming from?</h2>



What was adding CO₂ if not just magma? The 2023 study pointed to a second source: <a href="https://www.earth.com/news/plants-and-trees-predict-volcano-eruptions-when-viewed-from-space-satellites/">the hydrothermal system</a> heating the rocks themselves. 



In plain language, hot, reactive fluids were <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/decarbonation" target="_blank" rel="noreferrer noopener">decarbonating calcite</a> (a carbonate-rich mineral) in the shallow reservoir rocks and releasing additional CO₂. The team estimated that this non-magmatic source contributed about 20-40% of total CO₂. 



That finding did not make the volcano harmless - far from it - but it did change how scientists interpret gas alarms.



A spike in CO₂ at Campi Flegrei does not automatically mean magma is surging. Sometimes it means the hydrothermal system is getting hotter and more pressurized, which can still be hazardous but in a different way.



<h2 class="wp-block-heading" id="h-studying-campi-flegrei-in-2025">Studying Campi Flegrei in 2025</h2>



Fast forward 14 months to May 2025. A second group of scientists <a href="https://www.science.org/doi/10.1126/sciadv.adt2067" target="_blank" rel="noreferrer noopener">published a study</a> that asked a bigger question: what, exactly, is driving the recent bursts of earthquakes and the dramatic rise and fall of the ground? 



They pulled together two major episodes of unrest - 1982-1984 and 2011-2024 - then compared the patterns of uplift, seismicity, and subsurface imaging. 



In the lab, they simulated the rocks above the caldera using a setup like a moka pot, the stovetop espresso maker. 



A heated lower chamber (representing a <a href="https://www.earth.com/news/geothermal-energy-is-cheap-and-clean-and-having-its-moment/">geothermal reservoir</a>) pushed fluid into a cracked “lid” made of Campi Flegrei-like materials. The result of all that detective work was a new model with a crucial twist.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/supervolcano_campi-flegrei_location-satellite-view_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2024/12/supervolcano_campi-flegrei_location-satellite-view_1s.webp" alt="Satellite view Phlegraean Fields and Solfatara crater showing a massive caldera supervolcano named Campi Flegrei west of Naples, Italy. It is part of the Campanian volcanic arc, which includes Mount Vesuvius. Credit: Geology" class="wp-image-1982065"/></a><figcaption class="wp-element-caption">Satellite view Phlegraean Fields and Solfatara crater showing a massive caldera supervolcano named Campi Flegrei west of Naples, Italy. It is part of the Campanian volcanic arc, which includes Mount Vesuvius. Click image to enlarge. Credit: Geology</figcaption></figure>



<h2 class="wp-block-heading" id="h-how-supervolcano-pressure-builds">How supervolcano pressure builds</h2>



The central actor behind the building pressure inside Campi Flegrei is not a blob of rising magma in the upper crust; it is a capped geothermal reservoir sitting beneath the town of Pozzuoli. The caprock above it is fibrous and “self-healing,” which means cracks can seal up quickly. 



When the lid seals, water and steam trapped below it build pressure. Pressure builds until the rocks fracture, the water flashes to steam, producing a burst of shaking and noise - a pattern residents report. 



Interestingly, the <a href="https://www.earth.com/news/volcanic-tremors-can-now-be-detected-to-forecast-eruptions/">earthquakes in these sequences</a> tend to start shallow and then deepen over time, which is the opposite of what you would expect if magma or its gases were pushing upward from depth. 



After big episodes, the land actually sinks a bit, consistent with fluids discharging and pressure dropping.



<h2 class="wp-block-heading" id="h-why-does-any-of-this-matter">Why does any of this matter?</h2>



Here is the hopeful part. If the main driver of unrest is pressure in a closed, fluid-filled reservoir, then you can manage the fuel. 



You cannot turn off the “burner” heating the system - the deep magmatic heat source - but you can reduce the amount of water available to pressurize the reservoir. 



The researchers propose practical steps: restore and maintain surface-water channels so heavy rains do not funnel into the system; monitor and control <a href="https://www.earth.com/news/groundwater-has-a-vital-role-in-ecosystem-survival/" target="_blank" rel="noreferrer noopener">groundwater levels</a>; and, where appropriate, relieve pressure by withdrawing fluids through wells. 



Think of it like tending a radiator: keep the system from clogging or overfilling, and bleed off pressure before it blows a gasket.



<h2 class="wp-block-heading" id="h-campi-flegrei-eruption-risk">Campi Flegrei eruption risk</h2>



What does that mean for eruption risk? It does not mean Campi Flegrei is safe. A <a href="https://www.nhm.ac.uk/discover/what-is-a-supervolcano.html" target="_blank" rel="noreferrer noopener">supervolcano caldera</a> with Campi Flegrei’s eruptive history still sits atop a large population. Magma is still present at depth. 



The 2023 work showed that the hydrothermal system has been heating and releasing CO₂ in ways that track with ground uplift, while the 2025 work argues that pressure in the sealed geothermal reservoir can trigger swarms of shallow quakes and potentially steam-driven explosions (phreatic blasts). 



Both of those issues can be destructive, even without lava.



The new approach does not “turn off” a magmatic eruption if deep melt intrudes; it aims to prevent or reduce the kind of fluid-pressure crises that have damaged buildings and frightened residents for decades.



<h2 class="wp-block-heading" id="h-shifting-focus-and-mindset">Shifting focus and mindset</h2>



The key takeaway is a shift in mindset. For decades, <a href="https://www.usgs.gov/observatories/cvo/science/volcano-monitoring" target="_blank" rel="noreferrer noopener">volcano monitoring</a> focused on watching and warning: measure gases, track quakes, map ground motion, and be ready to evacuate. That is still essential. 



But if groundwater and surface runoff are a big part of the problem, civil engineers and geoscientists can work together on prevention.



They can unclog centuries-old drainage canals, divert stormwater, measure groundwater levels like a cardiologist tracking blood pressure, and - where science and policy align - use wells as pressure valves. 



None of this is a silver bullet for Campi Flegrei, or anywhere else. It requires careful design, community buy-in, and constant monitoring. 



But this appears to be a rare case in which a supervolcano’s most pressing threat is not an unstoppable magma surge; it is a pressure system that we might learn to regulate.



The full 2023 study was published in the journal <a href="https://pubs.geoscienceworld.org/gsa/geology/article/51/4/397/620796/Discriminating-carbon-dioxide-sources-during" target="_blank" rel="noreferrer noopener">Geology</a>.



The full 2025 study was published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.adt2067" target="_blank" rel="noreferrer noopener">Science Advances</a>.



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Supervolcano shows signs of waking up, which is not a good thing, but scientists have a plan

If you live around Naples, you know the ground breathes....

Extreme heat pushes the heart to work harder. On humid days, that strain can quickly shift from tolerable to dangerous - and a new analysis shows just how steeply the risk of weather-related heart problems rises.



Researchers in Dhaka, Bangladesh report that the chance of a cardiovascular emergency visit rises sixfold on days that are both extremely <a href="https://www.earth.com/news/astonishing-global-heat-in-january-2025-defied-climate-expectations/">hot</a> and very humid, compared with hot days when the air is much drier.



<h2 class="wp-block-heading" id="h-how-humidity-makes-heat-worse">How humidity makes heat worse</h2>



First author Mostafijur Rahman, an assistant professor of environmental health sciences at the Celia Scott Weatherhead School of Public Health (<a href="https://sph.tulane.edu/" target="_blank" rel="noreferrer noopener">SPH</a>) and Tropical Medicine at <a href="https://sph.tulane.edu/trmd/home" target="_blank" rel="noreferrer noopener">Tulane</a> University, led the research with collaborators in Bangladesh and the United States.



Humidity matters because sweat must evaporate to cool the body, and water-laden air stalls evaporation. The resulting strain raises body <a href="https://www.earth.com/news/more-heat-cleaner-air-the-surprising-ozone-connection/">temperature</a>, increases skin blood flow, and can load the heart with extra work that some people cannot sustain.



As humidity climbs, the same thermometer reading feels much hotter to the body. That mismatch helps explain why ordinary heat advisories sometimes fail to capture the real risk for people with heart disease.



“These findings show we need to consider heat and humidity together when we discuss any kind of climate change policy,” said Rahman, who noted that the size of the effect surprised the team.



<h2 class="wp-block-heading" id="h-heart-risks-intensified-by-high-humidity">Heart risks intensified by high humidity</h2>



The researchers counted 340,758 emergency department visits for heart conditions during the hot months from 2014 to 2019 and matched those days to weather records. 



Heat alone raised risk on low humidity days, but risk jumped far higher on the muggiest days when relative humidity exceeded roughly 82 percent.



High heat in the analysis was defined as above 84 degrees Fahrenheit, which raised heart related emergency visits even without intense humidity. There was no separate link between humidity alone and heart emergencies, yet humidity amplified heat <a href="https://www.earth.com/news/extreme-temperatures-are-killing-thousands-across-india/">effects</a> across age and sex groups.



“Hopefully governments will be spurred to develop systems to warn cities of dangerous heat and humidity. We know extreme heat can have a negative health impact, but I never expected such a dramatic increase in risk when high humidity is also factored in,” said Rahman.



The pattern is consistent with clinical experience. When sweat fails to evaporate, the heart must move more blood toward the skin for cooling, while dehydration and electrolyte loss further stress the system.



<h2 class="wp-block-heading" id="h-humidity-and-public-health-warnings">Humidity and public health warnings</h2>



Hot extremes are becoming more frequent and more intense as the planet warms, and that trend is evident with every additional 0.9 degrees Fahrenheit of global warming, according to the Intergovernmental Panel on Climate Change (<a href="https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf" target="_blank" rel="noreferrer noopener">IPCC</a>).



Independent research also links moist summer air to higher rates of heart, coronary, and stroke hospitalizations in older adults in the United States, even after accounting for temperature. 



A long-term analysis of about 63 million Medicare beneficiaries found higher cardiovascular hospitalization risks with higher summer-specific humidity.



Laboratory and field <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC10231239/" target="_blank" rel="noreferrer noopener">studies</a> add biological context. They show that humid heat undermines sweat evaporation and raises the physiologic load on the heart, validating the Dhaka pattern.



These threads point to one conclusion. Health systems and public warnings need to treat humidity as a co-equal driver of heat danger, not just a background variable.



<h2 class="wp-block-heading" id="h-access-to-cooling-matters">Access to cooling matters</h2>



Dhaka’s results are particularly relevant in places where home air conditioning is rare. Recent national survey <a href="https://www.seforall.org/taxonomy/term/38" target="_blank" rel="noreferrer noopener">reporting</a> in Bangladesh shows that only about 2.28 percent of households owned an air conditioner in 2023, a small rise from 1.6 percent in 2021.



Global analyses identify Bangladesh among countries with large populations at high risk due to a lack of access to affordable, sustainable cooling. Those gaps create exposure that individuals cannot easily avoid during multi day hot spells.



“There are billions around the world, from Southeast Asia to Africa, who are directly impacted by rising temperatures but have little access to air conditioning,” said Rahman. 



Equity is central here. The people least able to afford cooling often live and work in buildings and neighborhoods that trap heat, and they may have the most to lose from heart strain.



<h2 class="wp-block-heading" id="h-adapting-to-heat-and-humidity">Adapting to heat and humidity</h2>



Clinicians already flag combined heat and humidity as a risk for people with heart disease, heart failure, high blood pressure, prior stroke, and older age. 



Public guidance now acknowledges that humid heat can drive blood pressure swings and raise hospitalizations for those with cardiovascular conditions.



City agencies should tune heat warnings to humidity, not just temperature thresholds. Emergency managers could extend hours for cooling centers, stagger outdoor work schedules, and coordinate hydration and medication checks with community groups.



Individuals should plan around the weather forecast on humid <a href="https://www.earth.com/news/earth-is-just-three-years-away-from-dangerous-carbon-milestone/">hot</a> days. Small steps such as shortening exertion, spacing outdoor tasks, and favoring shaded or air conditioned spaces can spare the heart avoidable stress.



Health systems can prepare for surges. Hospitals and ambulance services can adjust staffing based on heat and humidity forecasts, which now provide advance warning of the most extreme events.



<h2 class="wp-block-heading" id="h-heart-risks-of-humidity-are-clear">Heart risks of humidity are clear</h2>



The Dhaka study is observational, and it uses outdoor weather to represent exposure, which cannot capture every indoor environment or personal behavior. 



Even so, the same day link between humid heat and heart emergencies aligns with physiology and persisted across sensitivity tests in the analysis.



Public agencies should incorporate humidity explicitly in heat alert systems. Common composites such as the <a href="https://journals.ametsoc.org/view/journals/apme/61/10/JAMC-D-22-0021.1.xml" target="_blank" rel="noreferrer noopener">heat index</a> were not designed for extreme combinations of temperature and humidity, and updated methods could improve their performance.



The Dhaka data highlight a simple truth: on hot, muggy days, the heart works overtime, and treating humidity as a key hazard in planning can save lives.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/pii/S0048969725018601?via%3Dihub" target="_blank" rel="noreferrer noopener">Science of The Total Environment</a>.



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Extreme heat and humidity sharply raise heart risks

Extreme heat pushes the heart to work harder. On humid...

River otters have roamed the shores and inlets of Chesapeake Bay for a long time. But there’s still a lot we don’t know about how they interact with their environment. What do they eat? Where do they hang out? And oddly enough - where do they go to the bathroom?



To answer these questions, researchers in Maryland spent nearly a year observing river otters and collecting data on their habits. 



The team, based at the <a href="https://serc.si.edu/" target="_blank" rel="noreferrer noopener">Smithsonian Environmental Research Center</a> (SERC), analyzed scat samples and habitat use to better understand the otters’ diet, behavior, and exposure to parasites.



Study senior author Dr. Katrina Lohan is a parasite ecologist and head of the Coastal Disease Ecology Laboratory at SERC.



“River otters in the Chesapeake Bay eat a wide range of animals, including those that live in the water and on land. <a href="https://www.earth.com/news/parasites-help-worker-ants-live-much-longer-lives/">Parasites</a>, too, are crucial parts of their diet,” said Dr. Lohan. "We also found that river otters use manmade structures for latrines or choose areas with specific characteristics.”



<h2 class="wp-block-heading" id="h-otter-poop-on-the-dock">Otter poop on the dock</h2>



It all started with an email. A colleague spotted some odd, watery scat on a dock and sent a message to Dr. Lohan. Inside the scat was a bright red worm. 



Cameras later confirmed that the dock had become a favorite toilet spot for a local river otter. This was the beginning of a full-scale study.



Graduate researcher Calli Wise took the lead on collecting samples. Over 11 months, she gathered scat from 18 active otter latrines. On average, each latrine held about 28 scat piles.



“Scats usually smelled strongly of fish and were full of scales or <a href="https://www.earth.com/news/new-invasive-crustacean-species-discovered-in-the-mediterranean/">crustacean</a> shells,” Wise said. “We wore gloves and used sterile tools and tubes to collect scat samples, to avoid contamination with other DNA.”



<h2 class="wp-block-heading" id="h-otter-toilets-are-social-hotspots">Otter toilets are social hotspots</h2>



The latrines aren’t just toilets. Otters use them to mark territory with urine and feces, but they’re also social spaces. 



Otters gather there to eat, play, and rest. The latrines often show signs of repeated use: flattened grass, worn vegetation, and nearby cover.



Most were located near the shoreline. The researchers found that otters liked areas with woody debris and easy access to the water. 



Some latrines stood out. Five were found directly on man-made features like docks, boardwalks, or stairs leading to the water.



<h2 class="wp-block-heading" id="h-what-the-otter-poop-reveals">What the otter poop reveals</h2>



The team used two main methods to analyze the samples: metabarcoding, which identifies DNA fragments, and traditional microscopy. Both approaches helped piece together what the otters had been eating - and what else they might be spreading.



“We collected most scats in the summer, when river otter diet is likely diverse,” Wise said. “We found evidence of invasive species like common carp and white river <a href="https://www.earth.com/news/bright-coloration-in-crayfish-does-not-serve-an-evolutionary-purpose/">crayfish</a> in river otters’ diet.”



The otters also ate American blue crabs, other fish, and crustaceans. Occasionally, they even consumed <a href="https://www.earth.com/news/how-ducks-balance-water-pressure-while-diving/">ducks</a> or <a href="https://www.earth.com/news/over-40-of-amphibians-face-extinction-due-to-escalating-climate-threats/">amphibians</a>.



But diet was just one layer. The scat also showed which parasites the otters were exposed to - either through their prey or directly. Most parasites infected teleost fish, the primary type of fish eaten by otters. A few may have infected the otters themselves.



“It is possible that river otters, like other top predators, wouldn’t be able to find enough food to eat without parasites,” noted Dr. Lohan.



<h2 class="wp-block-heading" id="h-why-parasites-might-be-a-good-thing">Why parasites might be a good thing</h2>



The researchers couldn’t identify every parasite. Gaps in DNA databases made some sequences impossible to match. They also couldn’t link poop to specific otters, so individual diets remain a mystery.



Still, the findings suggest otters might be playing an even bigger role in the ecosystem than we thought.



“Since so many of the parasites are actually infecting otters’ prey, it could mean that river otters are culling sick individuals from the populations they are preying upon,” explained Dr. Lohan.



Removing infected animals could reduce the spread of disease and even affect the gene pool of prey species. Sick animals don’t get to reproduce if they’re eaten. There’s also a potential connection to human health.



“Some of the parasites that infect river otters could potentially also infect humans, who also are mammals,” said Dr. Lohan. “Thus, we could use river otters as ‘disease sentinels,’ and study them to learn about what public health threats occur in certain areas.”



This study opens new questions about how river otters influence, and are influenced by, their environment. Their poop tells stories about what they eat, where they go, what parasites they host, and what role they might play in managing disease in coastal ecosystems.



And in Chesapeake Bay, it turns out those stories often start at a latrine - sometimes even on a dock.



The full study was published in the journal <a href="https://www.frontiersin.org/journals/mammal-science/articles/10.3389/fmamm.2025.1620318/full">Frontiers in Mammal Science</a>.



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What river otter poop reveals about life in Chesapeake Bay

River otters have roamed the shores and inlets of Chesapeake...

Sometimes, a white dwarf isn’t just a white dwarf. What seems ordinary at first glance can have a much more dramatic origin. That’s what astronomers discovered when they took a closer look at a star called WD 0525+526.



This compact, Earth-sized star appeared to be typical - but it wasn’t. Scientists found that it’s actually the aftermath of a stellar collision: two stars that crashed together and merged into one.



<h2 class="wp-block-heading" id="h-white-dwarf-with-a-violent-history">White dwarf with a violent history </h2>



White dwarfs mark the final stage of life for stars like our Sun. These stellar remnants are incredibly compact. One can pack more mass than the <a href="https://www.earth.com/news/team-creates-video-showing-the-sun-in-gamma-rays-over-a-14-year-period/">Sun</a> into a body no bigger than our planet. Most white dwarfs are born when a single star burns through its fuel and collapses.



But there’s another, rarer path. Sometimes two stars - often in a close <a href="https://www.earth.com/news/first-binary-star-system-d9-found-near-supermassive-black-hole-sagittarius-a-milky-way/">binary system</a> - collide and merge. The result is an ultra-massive white dwarf. That’s what happened with WD 0525+526, and this is the first time scientists have confirmed a merger origin based on ultraviolet evidence.



“It's a discovery that underlines things may be different from what they appear to us at first glance,” said Boris Gaensicke, principal investigator of the Hubble program at the <a href="https://warwick.ac.uk/" target="_blank" rel="noreferrer noopener">University of Warwick</a>. 



“Until now, this appeared as a normal white dwarf, but Hubble's ultraviolet vision revealed that it had a very different history from what we would have guessed.”



<h2 class="wp-block-heading" id="h-white-dwarf-transformed-by-a-merger">White dwarf transformed by a merger </h2>



Located 128 light-years from Earth, WD 0525+526 is 20% more massive than the Sun. Visually, it looks like any other white dwarf. But scientists used NASA’s Hubble Space Telescope and its ultraviolet capabilities to peer deeper into the star’s composition.



<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/nyWuLSIoosk?si=LgE0ox4Vv6Ojgx-Q
</div><figcaption class="wp-element-caption">Astronomers using NASA’s Hubble Space Telescope have found a rare ultra massive white dwarf formed from a stellar merger.</figcaption></figure>



The ultraviolet spectrum revealed something unexpected: <a href="https://www.earth.com/news/webb-finds-largest-amount-of-carbon-ever-seen-in-a-planet-forming-disk/">carbon</a> in the star’s atmosphere. Normally, white dwarfs formed from a single star have atmospheres made up of hydrogen and helium. Their carbon and oxygen are buried in the core, hidden under thick atmospheric layers.



Mergers, however, change the outcome. When two white dwarfs - or one and another type of star - crash into each other, the resulting explosion can strip away much of that outer hydrogen and <a href="https://www.earth.com/news/global-helium-supply-running-low-race-is-on-to-prevent-the-next-shortage/">helium</a>. What’s left is a thinner atmosphere, where carbon can leak up from the core and become visible.



<h2 class="wp-block-heading" id="h-detecting-carbon-in-the-star-s-atmosphere">Detecting carbon in the star's atmosphere</h2>



WD 0525+526 is hotter and more massive than the handful of other known merger-born white dwarfs. At nearly 21,000 kelvins (around 37,000 degrees Fahrenheit), it’s too hot for convection - the usual process that stirs carbon up into a white dwarf’s outer layers.



So how did the carbon get there? The researchers think a more subtle mechanism called semi-convection is at play. It’s a gentler process, but still powerful enough to pull a small trace of carbon to the surface.



What’s truly remarkable is how little carbon is in this star’s atmosphere - about 100,000 times less than what’s been observed in other merger remnants. This made it nearly impossible to spot without the right tools.



“Hubble's Cosmic Origins Spectrograph is the only instrument that can obtain the superb quality ultraviolet spectroscopy that was required to detect the carbon in the atmosphere of this white dwarf,” said study lead author Snehalata Sahu from the University of Warwick.



<h2 class="wp-block-heading" id="h-hidden-white-dwarf-mergers">Hidden white dwarf mergers </h2>



The discovery builds on a 2019 study using ESA’s <a href="https://www.earth.com/news/gaia-reveals-moons-around-hundreds-of-asteroids/">Gaia mission</a>, which identified a group of unusually blue white dwarfs. Some of those were later confirmed as the products of mergers. WD 0525+526 is now the hottest and most massive member of that group.



Because carbon in ultra-hot white dwarfs is easier to detect in ultraviolet than visible light, it’s possible many more of these cosmic collision survivors are out there - hiding in the data, waiting to be found.



“We would like to extend our research on this topic by exploring how common carbon white dwarfs are among similar white dwarfs, and how many stellar mergers are hiding among the normal white dwarf family,” said study co-author Antoine Bedrad.



“That will be an important contribution to our understanding of white dwarf binaries, and the pathways to <a href="https://www.earth.com/news/the-true-nature-of-dark-matter-may-be-revealed-in-a-supernova/">supernova</a> explosions.”



The research is published in the journal <a href="https://www.nature.com/articles/s41550-025-02590-y" target="_blank" rel="noreferrer noopener">Nature Astronomy</a>.



Image Credit: NASA, ESA, STScI, Ralf Crawford (STScI)



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Hubble spots a white dwarf created in a violent star collision

Sometimes, a white dwarf isn’t just a white dwarf. What...

Millions of adults will lose at least one permanent tooth, and many will lose several more as the years go by. In the United States alone, an estimated 178 million people are missing at least one tooth, which explains why dentures and titanium implants replacements are so common.



Dentistry is now aiming for something better, a living replacement that feels and functions like the original. The idea is not science fiction anymore, and it is moving from animal studies toward carefully designed human trials.



<a href="https://dental.tufts.edu/people/faculty/pamela-yelick" target="_blank" rel="noreferrer noopener">Pamela C. Yelick</a> of <a href="https://dental.tufts.edu/" target="_blank" rel="noreferrer noopener">Tufts University</a> School of Dental Medicine leads one of the teams moving this vision toward the clinic. A recent study from her and colleague <a href="https://dental.tufts.edu/people/faculty/weibo-zhang" target="_blank" rel="noreferrer noopener">Weibo Zhang</a> have pushed the conversation onto the main stage.



<h2 class="wp-block-heading" id="h-dentures-as-tooth-replacements">Dentures as tooth replacements</h2>



Tooth loss is not rare, and the burden rises with age worldwide. About 7 percent of people 20 or older have complete tooth loss, and that figure reaches 23 percent for those 60 or older.



Modern implants are anchored directly to the jaw through osseointegration, a concept that traces back to Per Ingvar Brånemark’s mid twentieth century work with titanium and bone. 



The history matters because it explains why implants are stable, and also why they do not feel like natural teeth.



Natural teeth are suspended in the socket by the periodontal ligament, which provides sensation and micro movement control that <a href="https://www.earth.com/news/scientists-successfully-grow-human-teeth-in-a-laboratory-for-the-first-time/">implants</a> lack. That difference shows up as reduced tactile sensitivity with implants compared with natural teeth.



Load also travels differently through an implant than through a tooth root cushioned by ligament fibers. Over time, that can contribute to bone loss around the fixture and biological complications that sometimes lead to failure.



<h2 class="wp-block-heading" id="h-two-routes-to-living-teeth">Two routes to living teeth</h2>



One route grows a replacement as a tissue, using a scaffold that guides cells to assemble into a tooth. 



In a recent large animal <a href="https://pubmed.ncbi.nlm.nih.gov/39729491/" target="_blank" rel="noreferrer noopener">study</a>, researchers used decellularized tooth bud scaffolds seeded with human dental pulp cells, porcine dental epithelial cells, and endothelial cells. 



They then implanted these constructs into adult minipig jaws where they formed tooth like tissues including periodontal ligament. 



The other route tries to spark tooth development in place by presenting the right developmental signals to adult cells. 



<a href="https://pubmed.ncbi.nlm.nih.gov/40120109/" target="_blank" rel="noreferrer noopener">Teams</a> mapping the choreography of early human tooth formation are building a playbook that identifies the epithelial and mesenchymal cues needed to kick off organized growth.



<h2 class="wp-block-heading" id="h-tooth-roots-and-ligaments">Tooth roots and ligaments</h2>



The scaffold approach matters because the emerging structures were not inert. 



They developed <a href="https://www.earth.com/news/dental-pulp-stem-cells-from-extracted-wisdom-teeth-can-treat-multiple-diseases/">tooth</a> supporting ligament and mineralized tissues in the socket and progressed over a period of months, which brings the approach closer to human scale.



“Even creating a tooth root that you could put an artificial crown on, with living dental pulp in the middle, secured by periodontal ligaments instead of being screwed into the jaw, could be a huge improvement to a person’s oral health and in turn, systemic health,” said Yelick.



<h2 class="wp-block-heading" id="h-protein-helps-tooth-replacement">Protein helps tooth replacement</h2>



A separate line of work targets a specific protein, <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC7880588/" target="_blank" rel="noreferrer noopener">USAG-1</a>, that suppresses tooth formation. Blocking USAG-1 in mice rescued missing teeth caused by different genetic problems, and the same strategy produced new incisors in ferrets, which share a human-like replacement pattern.



“Moreover, a single administration was enough to generate a whole tooth,” stated <a href="https://toregem.co.jp/en/about" target="_blank" rel="noreferrer noopener">Katsu Takahashi</a>, whose group <a href="https://www.kyoto-u.ac.jp/en/research-news/2021-03-31" target="_blank" rel="noreferrer noopener">reported</a> the antibody treatment while at <a href="https://www.kyoto-u.ac.jp/en" target="_blank" rel="noreferrer noopener">Kyoto University</a>.



A humanized anti USAG-1 antibody has been advanced by industry collaborators, with investigators reporting that a phase 1 protocol has been finalized and preparations for future studies are underway. 



That marks the shift from animal proof of concept to testing for safety, dosing, and early signals of activity in people.



Financing updates from partners indicate plans to run the first in human study and to prepare for subsequent pediatric trials if early results support it. 



The initial clinical focus is congenital tooth agenesis in young children, where a therapy that triggers tooth development could change lifelong care. 



<h2 class="wp-block-heading" id="h-what-would-count-as-success">What would count as success</h2>



A living <a href="https://www.earth.com/news/tooth-enamel-analysis-suggests-early-eurasians-were-multiple-species-paranthropus-robustus/">tooth</a> would restore ligament mediated sensation, which helps people modulate bite force and detect grit or high spots. It would also reconnect to bone through tissues that are built to bear chewing loads.



Those features could reduce pain and bone loss around a replacement compared with a rigid post. 



They could also lengthen functional life compared with today’s devices, which often need repair or replacement after years of wear.



<h2 class="wp-block-heading" id="h-what-about-cost-and-complexity">What about cost and complexity</h2>



Cell based therapies will only reach clinics if they can be produced reliably and priced within reach of today’s prosthetic options. 



Sourcing compatible epithelial cells at the right developmental stage is a known challenge, and that is why teams built their scaffolds around young pig tooth buds while they refine ways to recruit a patient’s own cells.



Work with induced pluripotent stem cells (<a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9065891/" target="_blank" rel="noreferrer noopener">iPSC</a>s) is also moving forward, including efforts to make enamel forming cells and repair enamel defects. 



As methods improve, the main questions will be safety, quality control, and whether costs can compete with implant dentistry.



<h2 class="wp-block-heading" id="h-tooth-replacement-and-future-tech">Tooth replacement and future tech</h2>



An atlas of human fetal tooth development now details epithelial subpopulations and their signaling to mesenchyme. 



That resource gives researchers the specific factors and timing likely needed to nudge adult cells toward making a new tooth unit.



If those cues can be delivered precisely, either by a staged therapy in the jaw or by organoid-like constructs that finish maturing in the socket, dentists could one day replace a lost tooth with a living one that integrates, remodels, and feels like it belongs.



The study is published in <a href="https://academic.oup.com/stcltm/article/14/2/szae076/7933795" target="_blank" rel="noreferrer noopener">Stem Cells Translational Medicine</a>.



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The end of dentures: Science is about to help you regrow your own teeth

Millions of adults will lose at least one permanent tooth,...

On May 12, 2008, central China was hit by one of the deadliest earthquakes in recent memory. The magnitude 7.9 Wenchuan Earthquake struck along the edge of the Tibetan Plateau, triggering violent landslides across the steep slopes of the Longmen Shan - known as the Dragon’s Gate Mountains.



The disaster killed more than 69,000 people, but nearly a third of those deaths weren't from shaking alone. They came from geohazards - including more than 60,000 landslides that came tumbling down the mountains in the hours and days that followed.



Now, after nearly two decades of research, scientists at <a href="https://www.ucsb.edu/" target="_blank" rel="noreferrer noopener">UC Santa Barbara</a> and the University of Southern California say the story of that earthquake still isn’t over. Their recent study shows that the debris shaken loose by the quake is still working its way through the region’s rivers. 



The team tracked how sediment surged into the Min River and how it changed the river’s behavior - possibly for decades. And their work could help answer a deeper question: Do earthquakes build mountains, or wear them down?



<h2 class="wp-block-heading" id="h-a-river-loaded-with-debris">A river loaded with debris</h2>



When the quake hit, millions of tons of rock and soil collapsed into nearby streams. Much of it ended up in the Min River, which runs through the Longmen Mountains. The river became a conveyor belt for that debris.



Geologists call this "<a href="https://www.earth.com/news/rivers-show-widespread-change-from-human-activity/">sediment flux</a>" - the amount of material a river carries. It shows up in two forms. The first is suspended sediment, fine particles carried in the water, easy to measure. The second is bedload - coarser stuff like gravel and boulders that roll or bounce along the bottom. That’s harder to track.



“Before our work, people mostly focused on the sediment of very fine size,” said Gen Li, an assistant professor in UC Santa Barbara’s Department of Earth Science.



Suspended sediment is routinely measured by agencies around the world. But bedload? That’s trickier. You can’t collect it with a bottle. And during an event like the Wenchuan Earthquake, there's suddenly a lot of it.



Scientists have long suspected that this surge in bedload plays a big role in <a href="https://www.earth.com/news/mega-tsunamis-triggered-by-earthquakes-could-wipe-part-of-us-off-the-map/">post-quake flooding</a>. The idea is simple: if a riverbed fills with debris, the channel gets shallower. Then, when a flood comes, it spills over more easily. But proving this has been a challenge.



<h2 class="wp-block-heading" id="h-how-a-dam-became-a-natural-lab">How a dam became a natural lab</h2>



Back in 2001, the Sichuan Provincial Electric Power Company started building the Zipingpu Dam. By 2006, the reservoir began filling, just 20 kilometers downstream from where the Wenchuan Earthquake would later strike. It was an unintentional stroke of luck for science.



That dam turned into the perfect sediment trap. Shortly after the quake, Li and his collaborators - including researchers from the <a href="http://www.cjh.com.cn/eng/" target="_blank" rel="noreferrer noopener">Chinese Bureau of Hydrology</a> - began surveying it.



Daily data already existed for suspended sediment. What the scientists needed was the rest of the picture. They set out, year after year, using sonar to map the floor of the reservoir. 



Each expedition added a new layer to their data. Over time, they could measure how much total sediment had built up. From there, they did the math. Total sediment minus suspended sediment equals bedload.



<h2 class="wp-block-heading" id="h-when-earthquake-effects-last-a-decade">When earthquake effects last a decade</h2>



After the quake, the amount of total sediment in the Min River grew sixfold. But the real shock came with the bedload, which had increased 20 times. That is not normal. Bedload usually makes up about 20% of sediment in a mountain river. Here, it made up 65 percent.



The result didn’t surprise co-author Josh West. He had suspected that sediment flux would spike after a <a href="https://www.earth.com/news/can-we-detect-major-earthquakes-months-in-advance/">major earthquake</a>, especially in the form of increased bedload.



What did surprise the team was how long it lasted. The elevated sediment flow didn’t return to normal after a few years. It stayed high for at least a decade.



“In fact, from the data we’ve collected so far, there’s no evidence yet of the total sediment flux declining back to background levels,” West said.



“Usually, we think the influence from earthquakes may last, at most, a few years after the main shock,” said Professor Li. “But this data shows that this is not true.”



<h2 class="wp-block-heading" id="h-earthquakes-set-off-a-chain-reaction">Earthquakes set off a chain reaction </h2>



The study adds weight to a growing idea among scientists: the danger from <a href="https://www.earth.com/news/natural-disasters-are-on-the-rise-but-hazard-plans-are-inadequate/">natural disasters</a> doesn’t stop once the main event ends. Earthquakes can set off a chain reaction. One disaster leads to another.



“Earthquake-triggered landslides are a great example,” West said. “As we prepare for natural disasters, we often think of them as being discrete events. But what’s left out of that is the longer tail that follows.”



In other words, rebuilding too quickly - or rebuilding in the same way, in the same place - can be risky. The land has changed. Riverbeds are higher and <a href="https://www.earth.com/news/earthquakes-and-flood-zones-hidden-risks-in-the-pacific-northwest/">flood zones</a> are different. What was once a safe 10-year floodplain may now be a ticking time bomb.



<h2 class="wp-block-heading" id="h-do-earthquakes-build-mountains">Do earthquakes build mountains?</h2>



Earthquakes are thought to push up mountain ranges. But they also cause <a href="https://www.earth.com/news/landslide-predictions-could-become-94-percent-more-accurate/">landslides</a> that scrape them back down. So which effect wins?



Professor Li looked into this in an earlier study. He used satellite images to estimate that the Wenchuan Earthquake caused about three cubic kilometers of material to slide off the Longmen Mountains. “That is around half of the sediment flux of all the rivers in the world over one year,” he said.



Li also looked at how much rock the quake pushed upward. Turns out, it was about the same. That means the quake may have added and removed equal amounts of mass. Whether the mountain grows or shrinks depends on what happens next.



If the river can carry all that debris away quickly, the mountain stays tall. If the debris piles up and clogs the system, the mountain starts to erode. So far, the Min River has flushed out about 10% of the landslide debris over ten years.



“The fact that the pace was sustained for ten years was a surprise on its own,” West said. But predicting what happens in the next few decades is harder. Watersheds evolve and landscapes shift. The balance is fragile.



<h2 class="wp-block-heading" id="h-many-questions-remain">Many questions remain</h2>



Professor Li is now investigating why this particular river carried so much bedload. The 2015 Gorkha Earthquake in Nepal, for instance, didn’t trigger the same kind of sediment surge in Himalayan rivers. This suggests other factors are at play.



The rock itself might be the key. Its type, texture, and how it breaks apart all affect how much debris a quake generates. The size of the grains also matters. And how those grains move downstream is still being modeled.



Li’s team is now studying these patterns in more detail - using field data and computer models to understand how sediment flows over time.



“It’s very satisfying to have been able to quantify something that we’ve struggled to quantify before and that has a wide range of relevance, from hazards to long-term consequences for understanding the evolution of topography over long periods of time," said West.



The full study was published in the journal <a href="https://www.nature.com/articles/s41586-025-09354-8" target="_blank" rel="noreferrer noopener">Nature</a>.



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How earthquakes move mountains - and what comes next

On May 12, 2008, central China was hit by one...

Researchers analyzing images from the James Webb Space Telescope report 300 unusually bright objects that vanish from bluer filters yet appear in redder ones, a classic signature used to flag very distant systems.



Some of these sources almost certainly belong to a closer crowd wearing heavy dust. Others could sit far back in cosmic time, where our current playbook for how <a href="https://www.earth.com/news/oxygen-detected-in-most-distant-galaxy-yet-cosmic-dawn-jades-gs-z14-0/">galaxies</a> grow gets stressed.



The research was led by Liu Bangzheng “Tom” Sun and Haojing Yan in the Department of Physics and Astronomy at the University of Missouri (<a href="https://physics.missouri.edu/news/campus-and-community-outreach" target="_blank" rel="noreferrer noopener">UM</a>).



<h2 class="wp-block-heading" id="h-jwst-finds-300-bright-objects">JWST finds 300 bright objects</h2>



The <a href="https://iopscience.iop.org/article/10.3847/1538-4357/addbe0" target="_blank" rel="noreferrer noopener">study</a> sifted public JWST images across four deep fields and cataloged 300 very bright “dropouts,” then focused on 137 objects that also have mid infrared measurements, a combination that helps rule in or rule out distant candidates.



Their modeling shows that most of these luminous dropouts are nearby in cosmic terms, likely at redshift z ≈ 1–4, while a nontrivial slice could be truly distant at z greater than 6, a mix that demands careful follow up.



“These mysterious objects are candidate galaxies in the early <a href="https://www.earth.com/news/milky-way-galaxy-may-be-inside-a-giant-void-in-the-universe-explains-hubble-tension/">universe</a>, meaning they could be very early galaxies,” said Haojing Yan, co-author of the study.



<h2 class="wp-block-heading" id="h-redshift-and-early-galaxies">Redshift and early galaxies</h2>



As light travels for billions of years, its wavelength stretches to the red end of the spectrum, a shift that pushes early galaxies out of optical reach and into the infrared. 



JWST’s Near Infrared Camera, <a href="https://jwst-docs.stsci.edu/jwst-near-infrared-camera" target="_blank" rel="noreferrer noopener">NIRCam</a>, is purpose built for that stretch to observe redshifts and sees from 0.6 to 5.0 microns.



The Mid Infrared Instrument (<a href="https://jwst-docs.stsci.edu/jwst-mid-infrared-instrument" target="_blank" rel="noreferrer noopener">MIRI</a>) extends that reach to roughly 5 to 28 microns, giving astronomers an extra set of eyes that can be decisive when red colors come from dust instead of distance.



The broader context is moving quickly. <a href="https://arxiv.org/abs/2405.18485" target="_blank" rel="noreferrer noopener">Spectroscopy</a> with JWST has now been locked in galaxies beyond redshift 14, showing that luminous systems were present only about 290 million years after the Big Bang.



“As the light from these early <a href="https://www.earth.com/image/hundreds-of-galaxies-illuminate-the-early-universe/">galaxies</a> travels through space, it stretches into longer wavelengths, shifting from visible light into infrared,” said Yan, explaining redshift.



<h2 class="wp-block-heading" id="h-high-redshift-dropout-technique">High-redshift dropout technique</h2>



The team used the “dropout technique,” which flags an abrupt loss of flux blueward of the <a href="https://adsabs.harvard.edu/full/1995AJ....110.2519S" target="_blank" rel="noreferrer noopener">Lyman break</a> and a clear detection just redward of that break, a method pioneered in the 1990s and refined ever since.



“It detects high-redshift galaxies by looking for objects that appear in redder wavelengths but vanish in bluer ones,” said Bangzheng “Tom” Sun, referring to the dropout signature tied to absorption by neutral hydrogen.



Color cuts are only the start. The team estimated photometric redshifts using three independent spectral energy distribution fitting tools, including Le Phare and EAZY, to weigh high redshift solutions against dusty, lower redshift impostors.



Spectroscopy remains the gold standard. It breaks a galaxy’s light into its component wavelengths and nails down spectroscopic redshift when emission lines are identified, which is why the authors call for more follow up.



<h2 class="wp-block-heading" id="h-one-extreme-bright-galaxy">One extreme bright galaxy</h2>



Among the sample sits a known source in the CEERS field at <a href="https://arxiv.org/abs/1507.02679" target="_blank" rel="noreferrer noopener">redshift z = 8.68</a>, originally identified from ground based Keck data because its infrared color hinted at strong oxygen emission, then studied repeatedly with JWST.



Later <a href="https://arxiv.org/abs/2303.08918" target="_blank" rel="noreferrer noopener">observations</a> revealed active black hole signatures in the same redshift neighborhood, including broad H beta emission that points to an accreting nucleus embedded in a vigorously star forming host.



That kind of source shows how a single, very bright object can be luminous for multiple reasons, from intense star formation to an active nucleus, and why mid infrared measurements help disentangle the power sources.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/08/potential-early-galaxies_300-observations_uds-field_JWST_UMissouri_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/08/potential-early-galaxies_300-observations_uds-field_JWST_UMissouri_1s.webp" alt="Graphic showing the mysterious objects with very high redshift, possibly early galaxies in the universe, that the University of Missouri researchers identified in their study. Credit: JWST/Bangzheng “Tom” Sun/University of Missouri" class="wp-image-1982072"/></a><figcaption class="wp-element-caption">Graphic showing the mysterious objects with very high redshift, possibly early galaxies in the universe, that the University of Missouri researchers identified in their study. Click image to enlarge. Credit: JWST/Bangzheng “Tom” Sun/University of Missouri</figcaption></figure>



<h2 class="wp-block-heading" id="h-early-galaxies-and-high-redshift">Early galaxies and high-redshift</h2>



The headline is not that every bright dropout is ancient, but that some probably are, and the brightest of those could stress current models if confirmed. 



Theoretical <a href="https://ui.adsabs.harvard.edu/abs/2023MNRAS.522.3986F/abstract" target="_blank" rel="noreferrer noopener">work</a> has shown that it is possible to reproduce many luminous early galaxies by dialing up star formation efficiency in massive halos at high density, yet the very brightest systems remain a challenge.



“Even if only a few of these objects are confirmed to be in the early <a href="https://www.earth.com/news/massive-black-hole-pushes-the-boundaries-of-whats-possible/">universe</a>, they will force us to modify the existing theories of galaxy formation,” said Yan.



Sun and Yan emphasize that spectroscopy will deliver the final word, since dusty galaxies at modest redshift can mimic the same colors that signal extreme distance. 



That caution is well placed, given how often the Lyman break can be confused with a strong Balmer break in redder, older systems.



The study is published in <a href="https://iopscience.iop.org/article/10.3847/1538-4357/addbe0" target="_blank" rel="noreferrer noopener">The Astrophysical Journal</a>.



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Mysterious bright objects found in space might be very early galaxies, or something else entirely

Researchers analyzing images from the James Webb Space Telescope report...

North American monarch butterflies do not use Earth’s magnetic field as a map to find Mexico. They use it as a compass to hold a heading, and cold temperatures later flip that compass for the return trip north.



In lab tests that mimicked different locations relative to their overwintering sites, fall migrants kept pointing toward the equator under every magnetic setting. 



After a 24 day chill, roughly 52ºF days and 39ºF nights, the same <a href="https://www.earth.com/news/butterfly-populations-are-disappearing-and-its-happening-fast/">butterflies</a> switched to a poleward heading, while controls kept aiming south.



A group of scientists in the Department of Biological Sciences at the University of Cincinnati (<a href="https://www.artsci.uc.edu/natural-sciences/biological-sciences.html" target="_blank" rel="noreferrer noopener">UC</a>) collaborated on the research 



<h2 class="wp-block-heading" id="h-monarch-compass-navigation">Monarch compass navigation</h2>



The team used a righting response setup inside a Helmholtz coil system, which generates controlled Earth-strength magnetic fields.



The butterflies oriented on a vertical mesh after righting themselves, giving clear headings without relying on visual landmarks.



The team tested three field conditions: locations about three days’ flight south of the overwintering sites, the overwintering sites themselves, and locations three days’ flight north. They then recorded the butterflies’ preferred direction.



The magnetic parameter that acts like latitude is inclination - the angle at which magnetic field lines enter the ground. It becomes steeper toward the poles.



<h2 class="wp-block-heading" id="h-cold-triggers-migration-change">Cold triggers migration change</h2>



“Our discovery that coldness triggers the northward flight direction in spring remigrants solves one of the long-standing mysteries of the monarch migration,” wrote Patrick A. Guerra, who led the study.



A decade ago, researchers showed that winter cold flips the monarch’s time-compensated sun compass, turning a fall southbound program into a spring northbound one.&nbsp;



The new study extends that logic to the magnetic system. Fall migrants chilled for 24 days under overwintering-like temperatures reversed their magnetic headings to poleward, while <a href="https://www.earth.com/news/butterfly-species-are-declining-fast-across-the-united-states/">monarchs</a> held at fall temperatures did not.



This points to temperature as a shared recalibration signal across compass systems. It also raises a practical question: how warm can the overwintering microclimate get before this switch fails to flip on schedule.



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



Rising winter temperatures in central Mexico could interfere with the recalibration process by preventing monarchs from experiencing the consistent cold needed to reset their orientation systems. 



Without this signal, they might depart on their spring migration still heading equatorward, wasting critical time and energy reserves.



Conservation strategies may need to account not only for preserving habitat but also for maintaining the microclimate stability of overwintering sites. 



Protecting forest canopy cover, limiting deforestation, and monitoring local weather trends could help ensure that <a href="https://www.earth.com/news/butterflies-can-adapt-quickly-but-evolution-has-its-limits/">monarchs</a> continue to receive the environmental cues they depend on for successful migration cycles.



<h2 class="wp-block-heading" id="h-a-compass-not-a-map">A compass, not a map</h2>



Several animals use geomagnetic information in two ways, as a compass for direction and as a map for position. 



Tests of fall monarchs have found no evidence that they possess a fine-scale magnetic map that could guide them to a specific Mexican mountain forest.



By contrast, some species do form magnetic maps that help them correct course or home to precise destinations. 



Evidence spans hatchling and adult sea turtles and at least some birds, where animals learn or inherit positional signatures in the field.



Monarchs likely lean on other cues to decide when to stop, including the cool, moist microclimate of oyamel fir forests at roughly 8,000 to 12,000 feet and consistent humidity in those groves. 



Those conditions bracket temperatures close to freezing up to about 59ºF, which help insects conserve energy until spring.



<h2 class="wp-block-heading" id="h-monarch-compass-works-without-sun">Monarch compass works without sun</h2>



“We now show that migratory monarch butterflies have an inclination magnetic compass that allows them to orient in the proper southern direction during the fall migration,” reported Guerra and colleagues. 



When the sun’s position is clear, monarchs use their sun compass. On overcast days, they can still stay on course with a light-dependent magnetic compass.&nbsp;



Recent genetics and neurobiology work has shown that the cryptochrome 1, a UV-A/blue-light sensitive protein, is essential to this magnetosensory response. Both antennae and eyes appear to serve as magnetosensory organs in this context.



Directional and timing cues are integrated in the brain’s central complex, a midline hub that combines skylight and clock information for orientation. Reviews of monarch neurobiology place this circuit at the center of migratory control.



<h2 class="wp-block-heading" id="h-travel-speed-and-timing">Travel speed and timing</h2>



Monarchs do not sprint to Mexico. Typical progress averages about 25 to 30 miles per day in reasonable weather, and it can stall or surge with changing winds.



Telemetry studies capture faster days under strong assistance, with a radio-tracked <a href="https://www.earth.com/news/a-country-without-butterflies-rapid-decline-in-u-s-populations/">monarch</a> covering about 89 miles in a single day. 



Temperature and wind together pushed that pace, demonstrating how sensitive the journey is to weather.



That sensitivity extends to winter. Federal assessments warn that changes to the oyamel fir belt, through logging and climate warming, threaten the microclimate that monarchs rely on to survive and to trigger their spring reorientation.



The study is published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0328737" target="_blank" rel="noreferrer noopener">PLOS ONE</a>.



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Monarch butterflies have a built-in compass that flips when it's cold, disrupting migration

North American monarch butterflies do not use Earth’s magnetic field...

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