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What is Cadmium?

Pain is not just a signal from skin or nerves. It is a decision made by your brain after weighing context, experience, and expectation, and a new study now shows that decision can be tuned to specific body parts.



Researchers found that placebo pain relief does not spread everywhere. It shows up mainly where your <a href="https://www.earth.com/news/pain-relief-breakthrough-as-scientists-discover-a-safer-non-addictive-approach-trpv1/">brain</a> expects it.



Dr. Lewis S. Crawford of the University of Sydney’s School of Medical Sciences and Brain and Mind Centre (<a href="https://www.sydney.edu.au/brain-mind/" target="_blank" rel="noreferrer noopener">BMC</a>) led the work. His team used ultra-high field functional magnetic resonance imaging (<a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC3073717/" target="_blank" rel="noreferrer noopener">fMRI</a>) to watch tiny brainstem hubs while people reported their pain.



<h2 class="wp-block-heading" id="h-pain-relief-follows-body-map">Pain relief follows body map</h2>



Your brainstem sits between the <a href="https://www.earth.com/news/virtual-nature-scenes-provide-relief-from-chronic-pain/">brain</a> and the spinal cord and helps regulate breathing, heart rate, and pain control. It routes signals to and from the body and houses chemical systems that set our internal state.



The team found that pain relief followed a spatial pattern. Facial pain relief linked to activity in higher brainstem regions while arm and leg relief tracked lower ones.



<h2 class="wp-block-heading" id="h-trained-spots-show-less-pain">Trained spots show less pain</h2>



Ninety-three healthy volunteers received heat pulses to the face, forearm, or leg. A sham cream labeled as a numbing agent was applied and the heat was quietly turned down during training so the cream seemed to work.



During scanning, the same heat was applied to the sham site and a control site with identical settings. Many people still reported less pain on the trained site, which reflects placebo analgesia.



<a href="https://www.earth.com/news/why-pain-feels-emotional-new-brain-pathway-linked-to-suffering/">Response</a> rates differed by location. Significant pain reductions appeared in 49 percent for face, 48 percent for arm, and 61 percent for leg.



Importantly, the relief stayed local. When a hidden cream was placed on a separate body site during scanning, the effect did not generalize to that new spot.



<h2 class="wp-block-heading" id="h-brainstem-zones-guide-placebo-signals">Brainstem zones guide placebo signals</h2>



Two brain regions did most of the work, the periaqueductal gray (PAG) and the rostral ventromedial medulla (RVM). These areas form a descending control system that can quiet incoming pain signals before they reach conscious awareness.



A recent <a href="https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2024.1380171/full" target="_blank" rel="noreferrer noopener">review</a> maps how different periaqueductal gray subregions support defensive actions and pain control. The new results fit that picture by showing location-specific changes for face versus limbs.



The periaqueductal gray appears to organize pain relief in a rostral to caudal gradient. The rostral end aligned with face-related relief and the caudal end with body-related relief.



The rostral ventromedial medulla showed a matching pattern. It linked rostral zones to face relief and more caudal zones to limb relief.



<h2 class="wp-block-heading" id="h-placebo-in-pain-relief">Placebo in pain relief</h2>



The periaqueductal gray has columns that support different <a href="https://www.earth.com/news/mindfulness-meditation-is-a-powerful-weapon-against-chronic-pain/">strategies</a>. The lateral column is tied to active coping and short-lasting, targeted analgesia, while the ventrolateral column is more associated with whole body opioid-driven analgesia.



This study points to the lateral column when placebo relief is spatially precise. That suggests a different chemistry may be at work than standard opioid circuits.



Cannabinoid signaling is one candidate within the periaqueductal gray. Evidence shows cannabinoids can reduce pain when engaged in this region.



A human and animal <a href="https://journals.lww.com/painrpts/fulltext/2021/01000/effects_of_inflammatory_pain_on_cb1_receptor_in.25.aspx" target="_blank" rel="noreferrer noopener">report</a> summarizes how cannabinoids in the periaqueductal gray influence antinociception and may contribute to descending control.



<h2 class="wp-block-heading" id="h-expectations-and-placebo-response">Expectations and placebo response </h2>



Expectations set during conditioning shaped the brainstem response. Relief appeared where people believed the cream would help and activity shifted in matching brainstem zones.



Ultra-high field scanning at 7 Tesla MRI made it possible to resolve these small nuclei. That level of detail is rare in human imaging and helped separate face-related and limb-related signals.



The effect was not all-or-nothing. Some participants did not show a measurable placebo response at a given site, which is consistent with known variability in placebo sensitivity.



Those who did respond showed changes in both periaqueductal gray and rostral ventromedial medulla that lined up with the trained body region.



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



If the brain controls pain with a map, treatment could be tuned to the right spot rather than blasting the whole system. This could reduce side effects and keep people alert and functional.



“This is the first time we’ve seen such a precise and detailed pain map in the human brainstem, showing us that it tailors pain relief to the specific part of the body that’s experiencing it,” said Dr. Crawford.



Opioid medications can quiet pain but often act broadly and carry risks when used long term. According to Dr. Crawford, a map-based approach could guide non-opioid strategies that target the right microcircuit.



“This could lead to more precise treatments for chronic pain that don’t rely on opioids and work exactly where the brain expects pain relief to occur."



<h2 class="wp-block-heading" id="h-why-pain-relief-varies-with-placebo">Why pain relief varies with placebo</h2>



Why did almost half of participants fail to show a significant placebo effect at some sites? Individual differences in learning, attention, and expectations likely play roles, along with subtle physiology in the descending system.



A timely <a href="https://pubmed.ncbi.nlm.nih.gov/40875865/" target="_blank" rel="noreferrer noopener">commentary</a> from the National Library of Medicine notes that identifying somatotopy in brainstem pain modulation could help in the management of chronic pain, where localized symptoms are common.



Researchers also need to determine which neurotransmitters drive the precise mapping. Opioids probably contribute in some circuits, while cannabinoids and other transmitters may shape lateral column effects.



Behavioral training that tunes expectations to match specific sites could enhance clinical results. Devices or medicines might then amplify that targeted control.



<h2 class="wp-block-heading" id="h-future-tests-of-placebo-effects">Future tests of placebo effects</h2>



Non-invasive stimulation methods could be tested to nudge the correct brainstem nodes while patients practice site specific expectation training. Imaging could confirm whether the right periaqueductal gray and rostral ventromedial medulla zones are engaged during therapy.



Drug development could also change. If a medicine claims to help a knee or jaw, imaging can check whether the matching brainstem segment lights up as expected.



Clinicians may one day combine modest doses of systemic drugs with local expectation training to get focused relief. The goal is steady function without heavy sedation or widespread side effects.



Patients with chronic, localized pain might benefit most from this approach. They could receive treatment plans that respect the map.



“The brain’s natural pain relief system is more nuanced than we thought,” said Dr Crawford. “Essentially, it has a built-in system to control pain in specific areas. It’s not just turning pain off everywhere; but working in a highly coordinated, anatomically precise system.”     



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adu8846" target="_blank" rel="noreferrer noopener">Science</a>.



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Placebo pain relief occurs where the brain expects it

Pain is not just a signal from skin or nerves....

Tropical forest loss is not just a story about trees. It is a story about people living next to those trees who are now facing hotter days and higher risks.



A new <a href="https://www.nature.com/articles/s41558-025-02411-0" target="_blank" rel="noreferrer noopener">study</a> reports that local warming from tropical deforestation is associated with 28,330 heat-related deaths per year across Central and South America, Africa, and Southeast Asia. 



The same analysis estimates that 345 million people were exposed to higher temperatures caused by nearby forest loss between 2001 and 2020.



The research was led by Dr. Carly Reddington and Professor Dominick Spracklen from the University of Leeds’ School of Earth and Environment (<a href="https://environment.leeds.ac.uk/see" target="_blank" rel="noreferrer noopener">UL</a>). The team worked with collaborators in Brazil and Ghana to connect satellite records of forest change and temperature with public health data. 



The work adds a direct human health lens to a topic often framed only as a climate or <a href="https://www.earth.com/news/international-day-for-biological-diversity-2025-bonding-with-nature/">biodiversity</a> problem.



<h2 class="wp-block-heading" id="h-how-deforestation-raises-heat">How deforestation raises heat</h2>



In simple terms, deforestation means permanent removal of tree cover from an area. The team mapped where tree cover declined and then measured how much land surface temperature rose in those same places.



They compared these deforested pixels to nearby pixels that kept their trees. That method isolates the heat tied to forest loss from broader climate trends.



The researchers overlaid population maps and national data on non-accidental mortality to estimate the share of heat-related mortality linked specifically to the added local heat from <a href="https://www.earth.com/news/global-deforestation-directly-linked-to-atmospheric-mercury-emissions/">deforestation</a>. 



The central estimate was 28,330 deaths per year, with the largest numbers in Southeast Asia due to larger exposed populations and higher vulnerability in many districts.



The analysis revealed that deforestation alone added about 0.81 degrees Fahrenheit of warming in deforested areas over 2001 to 2020. In places that lost forest, that local boost accounted for most of the warming people actually experienced.



<h2 class="wp-block-heading" id="h-trees-keep-areas-cool">Trees keep areas cool</h2>



Trees cool the air through evapotranspiration, where water moves from leaves to the atmosphere. This process removes heat, while shade further limits surface warming at midday.



A global <a href="https://www.science.org/doi/10.1126/science.aac8083" target="_blank" rel="noreferrer noopener">analysis</a> has shown that when forests are cut, nearby air temperatures rise and daily temperature swings grow larger. When the canopy is lost, the land loses both its source of moisture and its shield from the sun.



The burden is not spread evenly. Regions of Southeast Asia that lost forest had the highest heat-related mortality rates in the new dataset.



Populations working outdoors, living in rural areas, or lacking access to cooling face greater exposure. Health systems with fewer resources also struggle more during heat spikes.



<h2 class="wp-block-heading" id="h-heat-related-deaths-from-deforestation">Heat-related deaths from deforestation </h2>



Local case studies back up the pan-tropical picture. In Berau Regency, Indonesia, a modeling study showed that deforestation between 2002 and 2018 raised population-weighted mean temperatures by 1.55°F.



The researchers estimated that 7.3 to 8.5 percent of all-cause deaths in 2018 in Berau were linked to the combined warming from deforestation and climate change. 



In the current study, the experts estimate that deforestation alone can account for over a third of heat-related deaths where forest loss occurred.



<h2 class="wp-block-heading" id="h-forest-loss-and-outdoor-work">Forest loss and outdoor work </h2>



Heat does not just affect mortality. It also limits safe time for labor, especially in agriculture and construction.



Independent research shows that deforestation-driven warming reduced safe outdoor working hours for about 2.8 million workers across the tropics in recent years. 



Lost work time means lost income, and it increases health risks for those who continue laboring in dangerous conditions.



<h2 class="wp-block-heading" id="h-local-impact-of-deforestation">Local impact of deforestation</h2>



We often talk about <a href="https://www.earth.com/news/forests-are-lagging-centuries-behind-in-climate-adaptation/">forests</a> as carbon stores. That is true, but the cooling services that trees provide to neighboring communities are immediate and local.



The Leeds study shows that in areas with forest losses, local biophysical warming from deforestation explained most of the temperature rise that residents felt. 



This explains why people living near cleared land notice sharper heat compared to those located a short distance away near intact forest.



<h2 class="wp-block-heading" id="h-deforestation-adds-to-global-heat">Deforestation adds to global heat</h2>



Heat is already a leading environmental risk for health worldwide. A global <a href="https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196%2821%2900081-4/fulltext" target="_blank" rel="noreferrer noopener">study</a> estimated that non-optimal temperatures were associated with about 5.08 million deaths per year from 2000 to 2019.



Deforestation adds fuel to that fire by removing local cooling in some of the hottest, most humid places on Earth. It does so alongside rising greenhouse gases that are lifting baseline temperatures.



<h2 class="wp-block-heading" id="h-actions-to-protect-people">Actions to protect people </h2>



Stopping further loss of tropical forests can quickly lower local <a href="https://www.earth.com/news/extreme-heat-is-pushing-parts-of-earth-beyond-human-survival/">heat stress</a>. Keeping canopy intact restores shade and evapotranspiration, which cools surfaces and the air above them.



At the same time, communities need basic protections, including shade structures, water, rest breaks, and early warning for dangerous heat. Where possible, improving access to efficient cooling can protect health while limiting extra emissions.



The study is published in the journal <a href="https://www.nature.com/articles/s41558-025-02411-0" target="_blank" rel="noreferrer noopener">Nature Climate Change</a>.



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Millions exposed to deadly heat from deforestation

Tropical forest loss is not just a story about trees....

A construction crew cleared out what used to be an ice cream parlor in Gdańsk, Poland, and archaeologists stepped in to check the ground before redevelopment. They did not expect to uncover a full medieval skeleton lying beneath a carved grave stone.



The stone shows a knight in chainmail with a sword and shield, and likely dates to the late 1200s or early 1300s. The slab is about 59 inches (1.5 meters) long, and many of its details have survived.



<h2 class="wp-block-heading" id="h-well-preserved-skeleton-found">Well-preserved skeleton found</h2>



Sylwia Kurzyńska, an archaeologist with <a href="https://www.archeoscan.com/" target="_blank" rel="noreferrer noopener">ArcheoScan</a>, led the work and described the rare stone slab carved from Gotland limestone that appears to have been imported across the Baltic Sea.&nbsp;



“Given that it was made out of soft limestone and lay buried for centuries, the preservation of the slab is remarkable,” said Kurzyńska. Her team removed the stone and uncovered a well preserved male skeleton below it.



The burial lies within a medieval cemetery where nearly 300 <a href="https://www.earth.com/news/dna-study-changes-what-we-knew-about-irelands-oldest-graves/">graves</a> have been recorded, and only a handful carry stone tomb markers that signal elite status. That fits the visual language of the slab.



Archaeologists working in the same block had already identified that oak used to form the earliest church was cut in 1140. The area formed part of an early stronghold used from the late 1000s to the early 1300s. 



The churchyard’s location, inside the power center of the old town, helped explain why a high status grave turned up here.



<h2 class="wp-block-heading" id="h-high-ranking-man-under-grave-stone">High-ranking man under grave stone</h2>



Most late medieval memorials in this region are simple slabs with crosses or short inscriptions. <a href="https://howardwilliamsblog.wordpress.com/2017/07/12/medieval-effigies-comparative-expressions/" target="_blank" rel="noreferrer noopener">Effigial</a> carving, where the stone carries a full body image of the deceased, appears far less often and points to wealth, tools, and specialized carvers.



The material adds another layer. Gotland limestone took a fine polish and allowed crisp details. 



Traders moved it along Baltic routes that connected Poland with Swedish quarries and Hanseatic markets. An imported stone in a church floor hints at long distance ties that mattered for prestige.



The <a href="https://www.earth.com/news/dna-from-9000-year-old-skeletons-disproves-migratory-waves-theory-from-south-africa/">skeleton</a> belonged to an adult man with sturdy bones and no grave goods, an absence that sometimes reflects church rules rather than rank. 



The raised sword and sculpted armor communicate status in a way that parishioners would have understood during services.



All available evidence suggests that the individual was of high social standing, most likely a knight or a military commander. The visual program on the slab carries that message without a written epitaph.



<h2 class="wp-block-heading" id="h-skeletons-give-data-on-diet-and-disease">Skeletons give data on diet and disease</h2>



Height does not map neatly onto wealth, since it reflects nutrition, infection, and genetics. Medieval Polish datasets show wide ranges, and <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC7424595/" target="_blank" rel="noreferrer noopener">researchers</a> analyze stature in a biocultural framework to avoid simple one-cause stories.&nbsp;



Studies of medieval populations in Poland use skeletons to track diet and disease stress, not just inches and feet. That kind of work helps separate personal traits from community level conditions.



The grave stone was transferred to the Archaeological <a href="https://archeologia.pl/en/" target="_blank" rel="noreferrer noopener">Museum</a> in Gdańsk on July 8, 2025, for cleaning, stabilization, and documentation. 



Conservators plan high resolution imaging to capture the carving and any tool marks that survive.



On the skeleton, teams will run genetic tests alongside chemical work that can trace childhood and adult diets. A facial reconstruction will use skull measurements to create a research-based portrait for public display.



<h2 class="wp-block-heading" id="h-grave-stone-traded-from-across-the-sea">Grave stone traded from across the sea</h2>



Gdańsk stood in the middle of busy Baltic trade, so stone, iron, and timber moved between ports in short coastal hops. That system made it practical to import a fine limestone slab from Sweden for a prominent burial.



The stone also signals taste, since carvers familiar with regional styles could sell their skills across borders. A figure shown with a sword and shield fits a shared visual code that circulated on both sides of the sea.



A single grave can tighten a city’s timeline. This one ties a place of worship, a military seat, and a <a href="https://www.earth.com/news/archaeologists-find-a-luxurious-4000-year-old-tomb-for-a-teenager-with-gold-jewelry-and-mysterious-seals/">cemetery</a> together. They form a coherent picture that is anchored in wood from 1140 and carried forward into the 1300s.



It also frames open questions that only lab work can answer. Identity, origin, and life history will depend on careful analysis rather than guesswork.



<h2 class="wp-block-heading" id="h-how-the-past-becomes-public">How the past becomes public</h2>



Finds like this move quickly from trenches to museum benches, and then into classrooms and city tours. The story turns abstract ideas like sepulchral art into something concrete and local.



Public interest keeps momentum going, which helps fund analysis and conservation. That is how one carved stone becomes part of a shared record of the city’s past.



Photo source: ArcheoScan – Archaeology and Conservation Laboratory.



Information from a <a href="https://www.gdansk.pl/wiadomosci/Znaleziono-kompletny-szkielet-rycerza-Gdansk-archeologia,a,291781" target="_blank" rel="noreferrer noopener">press release</a> on the Gdańsk official website.



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What looked like an ice cream shop concealed a cemetery with nearly 300 graves

A construction crew cleared out what used to be an...

Birdwatching was once a quiet, eccentric pastime. Now, it’s a worldwide phenomenon. Travelers go thousands of miles - even to remote places such as the Andes in Colombia - to catch a glimpse of one species. 



In the process, birdwatchers bond with the natural world, interact with fellow travelers, and spend money - lots of it. 



Now, birdwatching is one of the major engines of ecotourism, particularly in the tropics where <a href="https://www.earth.com/news/all-birds-one-tree-complete-evolutionary-map-reveals-hidden-links/">bird</a> populations are rich and varied. But according to new research, not every country with rare birds is cashing in on this trend.



<h2 class="wp-block-heading" id="h-birdwatching-as-a-growing-business">Birdwatching as a growing business</h2>



Over the past decade, birdwatching has gone through the roof. Apps such as <a href="https://www.earth.com/news/machine-learning-may-solve-the-mystery-of-bird-movements/">eBird</a>, which allow users to record sightings, have made birdwatching a worldwide community. They receive millions of checklists from users who record what birds they have spotted and where.



The data is especially valuable for researchers trying to figure out how birdwatching tourism works - and where it’s growing.



A group of scientists from the <a href="https://www.ucsc.edu/">University of California, Santa Cruz</a> decided to dig into this question. They analyzed eBird records for 155 nations from 2010 to 2022. 



The goal was to learn why birdwatching tourists are drawn to certain places and why others receive more visits than others.



The team started by determining which app users were likely tourists. If a user mostly posted bird sightings in one country but also submitted checklists from others, those other sightings were counted as tourism. 



Next, the researchers built models to analyze which factors were tied to rising tourist activity.



<h2 class="wp-block-heading" id="h-more-birds-more-tourists">More birds, more tourists?</h2>



You’d think countries with the most birds would attract the most birders. That’s partly true - but it’s not the whole story.



The researchers looked at four main factors to understand what drives birdwatching tourism. First was the total number of <a href="https://www.earth.com/news/hundreds-of-bird-species-face-extinction-risks-in-the-neotropics/">bird species</a> in a country. They also considered the number of small-range species - birds that are found only in a very specific area. 



Beyond <a href="https://www.earth.com/news/global-biodiversity-crisis-is-actually-worse-than-we-thought/">biodiversity</a>, the team included the Human Development Index, which measures education, health, and income levels. Lastly, they factored in the Global Peace Index, which reflects a country’s overall safety and stability.



<h2 class="wp-block-heading" id="h-factors-influencing-bird-tourism">Factors influencing bird tourism </h2>



The analysis showed that the most important factor wasn’t birds - it was development. A country’s Human Development Index explained 41.4 percent of the variation in bird tourism. 



Species richness came in second at 22.4 percent. Small-range species mattered too, but not as much. Surprisingly, safety had only a minor influence - just 1.4 percent.



That means tourists care more about basic infrastructure and services than they do about peace rankings. They want to go somewhere that’s easy to travel in, not necessarily somewhere that’s totally safe on paper.



<h2 class="wp-block-heading" id="h-colombia-takes-the-lead">Colombia takes the lead</h2>



One of the biggest winners in the study was Colombia. Since 2010, birding activity in the country has grown 40 times over. 



The country also saw the biggest growth in tourist birdwatching, specifically. Colombia now holds a much bigger slice of the global birding pie than it did a decade ago.



South Africa ranked second in growth overall. Other countries, like Costa Rica, Mexico, Ecuador, and Peru, also scored high in both visitation and biodiversity.



But some tropical countries, including Venezuela, Bolivia, Madagascar, Papua New Guinea, and the Democratic Republic of Congo, barely saw any growth - even though they have incredible birds.



The gap is especially striking between Colombia and Venezuela. Both have rich bird life and similar development scores, but their tourism outcomes couldn’t be more different.



<h2 class="wp-block-heading" id="h-what-s-working-and-what-isn-t">What’s working - and what isn’t</h2>



Part of Colombia’s success might come down to smart promotion. The country’s tourism agency launched a major campaign to boost birdwatching. 



Meanwhile, places like Costa Rica have spent years building infrastructure - trails, towers, trained guides - and focusing on <a href="https://www.earth.com/news/travelers-are-ready-for-more-affordable-eco-friendly-options/">sustainable travel</a>. That kind of investment pays off.



On the other hand, some countries just haven’t built the conditions needed to welcome tourists, even if they have world-class birds. 



The study also suggests other factors might be in play: ease of getting visas, how affordable flights are, how a country is seen politically, and how well-connected it is to major tourist source countries like the U.S.



“Over the years, we’ve seen Colombia really explode as a birdwatching destination, and we often asked ourselves why more countries aren’t similarly recognized as great places for birdwatching,” said Scott Winton, a UC Santa Cruz ecologist and study coauthor.



<h2 class="wp-block-heading" id="h-birdwatching-as-a-business-opportunity">Birdwatching as a business opportunity</h2>



The researchers say there are ways to grow <a href="https://www.earth.com/news/birdwatching-boosts-alaskas-economy-by-hundreds-of-millions/">birdwatching tourism</a> - especially for countries in the tropics with untapped potential.



One important takeaway: it’s not all or nothing. A nation doesn’t necessarily have to be completely developed or 100% secure to attract birders. What is more important is whether certain areas are perceived as safe, boast trained local guides, and provide minimal amenities.



To get there, governments can facilitate the growth of birding tourism by providing tax incentives or low-interest loans to facilitate the construction of birding trails, canopy towers, and viewing hides. 



Investing in guide training can also go a long way, particularly if locals are equipped with bird identification and customer service knowledge. Preserving bird habitats is important, as ecotourism relies on maintaining these areas intact. 



Furthermore, investing in small, community-based tourism enterprises with incentives for sustainable activities can help make birding tourism more accessible and inclusive.



<h2 class="wp-block-heading" id="h-birdwatching-biodiversity-and-income">Birdwatching, biodiversity, and income</h2>



Birdwatching isn’t a shortcut to success. It requires long-term thinking. Natural habitats take years to recover if they’re destroyed, but tourism built around nature can last for generations. Still, it’s not a decision governments should make alone.



“Just as I’ve seen birding tourism change people’s lives in my native Colombia, I hope other tropical countries can come together to conserve and showcase their amazing bird capital,” said Natalia Ocampo-Peñuela, the study’s lead author.



Ultimately, local and Indigenous communities should have the final say. When they lead, and when the land is protected, birdwatching can be more than a hobby - it can be a way to protect biodiversity and build lasting income in places that need it most.



The full study was published in the journal <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1002/pan3.70105">People and Nature</a>.



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Birdwatching is big business, but not all countries benefit

Birdwatching was once a quiet, eccentric pastime. Now, it’s a...

The story of how horses became calm enough to carry people is written in their DNA. A new study tracked ancient horse genomes across thousands of years and connected specific genetic changes to behavior and body shape.



The work shows that early breeders first favored temperament, then selected for <a href="https://www.earth.com/news/horse-genetics-could-unlock-breakthroughs-in-human-medicine/">bodies</a> that could handle speed, weight, and long travel. 



The research also pinpoints one region in the genome that appears to have tipped the balance toward rideability.



<h2 class="wp-block-heading" id="h-horses-changed-human-life">Horses changed human life</h2>



Xuexue Liu led the project at the Institute of Animal Science, Chinese Academy of Agricultural Sciences (<a href="https://ias.caas.cn/en/" target="_blank" rel="noreferrer noopener">CAAS</a>), working with collaborators in France and Switzerland. 



Horses reshaped how people moved, traded, and fought. Archaeology and genetics place the successful spread of modern domestic horses in the Western Eurasian steppes a little over 4,000 years ago. 



A 2021 <a href="https://www.nature.com/articles/s41586-021-04018-9" target="_blank" rel="noreferrer noopener">study</a> linked the rise of horse domestication to new ways of moving across land using chariots and horseback.



Before engines, horses were the fastest way to move people and goods. They also pulled plows and carried messages over long distances, which pushed cultures into closer contact.



Those changes relied on <a href="https://www.earth.com/news/all-domestic-horses-have-ancestors-in-russia/">animals</a> that would accept a rider and keep pace without breaking down. The new genetic timeline helps explain how that happened step by step.



<h2 class="wp-block-heading" id="h-scanning-horse-dna">Scanning horse DNA</h2>



The researchers built a time series of horse DNA and scanned 266 trait linked markers tied to behavior and body conformation. They watched how those markers rose or fell in frequency as humans started managing horse breeding.



They found clear signals that early selection focused on <a href="https://www.earth.com/news/saving-przewalskis-horse-the-last-surviving-species-of-wild-horse/">behavior</a>. That pattern fits the simple idea that a trainable, steady animal is easier to handle before people attempt fast travel or combat.



The team also defined several key terms that matter for reading the data. Ancient DNA refers to genetic material recovered from archaeological remains, and a genome is the full set of genetic instructions in an organism.



A genetic locus is a specific location on a chromosome, and an <a href="https://www.genome.gov/genetics-glossary/Allele" target="_blank" rel="noreferrer noopener">allele</a> is a version of a gene at that location. When an allele becomes more common because it helps survival or success under human choice, that rise is called positive selection.



<h2 class="wp-block-heading" id="h-gene-linked-to-rideability">Gene linked to rideability</h2>



One region named GSDMC stood out as the strongest candidate for rideability. The team reports that selection at this locus started about 4,750 years ago, with the period known as a <a href="https://www.sciencedirect.com/science/article/abs/pii/S1871141308000747" target="_blank" rel="noreferrer noopener">domestication bottleneck</a> marking a sharp shift in breeding.



By about 4,150 years ago, variants in GSDMC had become very common in managed horse populations. The study links GSDMC genotypes to skeletal conformation in horses and to spinal anatomy, motor coordination, and muscular strength in mice.



Those traits align with the demands of carrying a human across uneven ground for many miles. A stiffer, stronger back, coordinated movement, and adequate muscle power would all contribute to a safe, steady ride.



The authors argue that selection on existing variation, not a brand new mutation popping up out of nowhere, likely fueled the rapid rise. That interpretation matches how breeders often work, choosing among the <a href="https://www.earth.com/news/ancient-dna-reveals-37000-years-of-hidden-human-infections/">animals</a> already in their herds.



<h2 class="wp-block-heading" id="h-calm-horses-chosen-first">Calm horses chosen first</h2>



The scan also flagged <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=ZFPM1" target="_blank" rel="noreferrer noopener">ZFPM1</a>, a gene known to modulate behavior in mice, as showing positive selection roughly 5,000 years ago. 



The timing hints that calm temperament and tractability came before the body tweaks that made sustained riding possible.



Taming an animal that is large, fast, and easily spooked would be the first hurdle. Once that gate is opened, people can begin to select for efficient movement and strength under load.



<h2 class="wp-block-heading" id="h-bronze-to-iron-age-changes">Bronze to Iron Age changes</h2>



The data suggest a shift in emphasis after the earliest phase of domestication. From the Iron Age onward, breeding leaned harder into larger body size and greater tameness to meet the demands of transport and warfare.



That pattern mirrors the archaeological record that shows more widespread cavalry and heavier equipment later in time. Stronger, bigger horses would be better suited for those roles.



<h2 class="wp-block-heading" id="h-horse-dna-shows-change">Horse DNA shows change</h2>



Time series genetics works because DNA from different ages acts like snapshots, and many snapshots form a timeline. 



With enough samples, researchers can watch allele frequencies move, which tells a story about selection pressure over centuries.



The team cross-referenced genetic markers for behavior and body plan with known timelines for human mobility. That combination helps separate changes driven by people from natural drift, and it points to windows when breeding priorities changed.



<h2 class="wp-block-heading" id="h-why-horse-dna-gene-matters">Why horse DNA gene matters</h2>



GSDMC is a plausible hub because it influences how the spine and muscles develop and function. A back that holds form under a rider without undue flexion would reduce pain and injury risk for the animal.



Coupled with better coordination and strength, the same horses could cross long distances at sustained paces. That capacity would give groups who bred and used them a real advantage in moving, trading, and waging war.



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



The exact group or culture that first pushed rideability to center stage remains uncertain. The genetic clock narrows the window, yet it does not name the horse herders who made those early choices.



Future work could refine which specific variants in GSDMC matter most and test how they affect motion in living horses. 



Ethical breeding today also has to balance performance with welfare, since back health is central to a horse’s quality of life.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/science.adp4581" target="_blank" rel="noreferrer noopener">Science</a>.



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Horse DNA reveals how humans bred calm animals

The story of how horses became calm enough to carry...

Evolution does not only respond to rivals, predators, or mates that bump into each other. It can also respond and evolve when ripples move through the environment and reach species that never cross paths, as shown in a new study.



Researchers tracked a simple question with big consequences: Could one species change the evolution of another without ever meeting it face to face?



The team studied indirect ecological effects, where one species influences another through a third species or by altering the environment rather than through direct contact. These effects can even cross habitat boundaries - as when land insects shape aquatic grazers - and, unlike obvious interactions such as predation or competition, they often go unnoticed.



The study was led by Shuqing Xu at <a href="https://www.uni-mainz.de/en/" target="_blank" rel="noreferrer noopener">Johannes Gutenberg University Mainz</a> and follows a long tradition of testing evolution in near-natural settings rather than only in small lab containers.



<h2 class="wp-block-heading" id="h-experimental-ponds-track-evolution">Experimental ponds track evolution</h2>



The researchers set up large outdoor mesocosms, which are controlled experimental ponds that mimic nature while allowing careful measurements. These systems were large enough to include many natural processes but controlled enough for clear tests. 



Each pond held about 4,000 gallons of water, plus aquatic plants, algae, and the tiny crustacean <a href="https://www.earth.com/news/lifes-rules-natural-selection-change-significantly-often-daphnia/">Daphnia</a>. The researchers added aphids that feed on duckweed to some ponds and kept other ponds as controls without aphids. 



That created two worlds that never connected directly, since the aphids lived on floating macrophytes (larger aquatic plants like duckweed) while zooplankton and Daphnia (small drifting animals) as well as phytoplankton (microscopic algae) swam below.



"We showed that land-based aphids influenced the evolution of Daphnia, a tiny aquatic crustacean, even though the two species never come into contact," said Xu.



The researchers carefully tracked environmental change and genetic change at the same time. The ponds allowed the team to connect cause to effect without guessing.



<h2 class="wp-block-heading" id="h-nutrients-and-heat-shift">Nutrients and heat shift</h2>



When aphids heavily consumed duckweed, the floating plant thinned out. With less cover, more light penetrated the water, and pond phytoplankton flourished - providing extra food for Daphnia.



The result was a sustained increase in Daphnia numbers in aphid ponds compared to controls, along with measurable shifts in nutrients and water temperature.



For example, there was a roughly 71.5 percent jump in total phosphorus, plus higher underwater light and a small temperature rise.



<h2 class="wp-block-heading" id="h-species-evolve-under-pressure">Species evolve under pressure</h2>



Evolution leaves fingerprints in <a href="https://www.earth.com/news/hidden-chapter-in-human-evolution-revealed-through-genetics/">DNA</a>. Whole genome sequencing showed that Daphnia in aphid ponds and Daphnia in control ponds diverged at many genomic sites, and the fraction of significantly different SNPs grew from one year to the next.



Population divergence increased across the experiment, and the team identified more than one hundred variants with strong treatment differences. 



These genome-wide signals track with well-known resistance loci in Daphnia and support adaptive change in response to the altered environment.



<h2 class="wp-block-heading" id="h-adaptation-came-with-a-cost">Adaptation came with a cost</h2>



Transplant tests provided the decisive check on whether the observed genetic change was beneficial or just random drift.



Daphnia that evolved in aphid ponds performed better back in aphid ponds than in control ponds.



There was a trade-off: the same aphid-pond lineages performed worse when moved into control conditions, a classic cost of specialization that often follows rapid adaptation.



<h2 class="wp-block-heading" id="h-species-shifts-spark-ripples">Species shifts spark ripples</h2>



The quality of algal food matters as much as the quantity. Some <a href="https://www.earth.com/news/turning-plants-into-carbon-capture-machines-with-cyanobacteria/">cyanobacteria</a> provide poor nutrition - or are even harmful - for Daphnia, and their abundance shifted during the experiment. 



Independent studies explain why this matters: cyanobacteria are difficult for Daphnia to process and lack the key lipids the crustaceans need. 



These changes in the water column did not stop with Daphnia. They rippled outward, altering duckweed and boosting the growth of aphids, which thrived in ponds shaped by earlier herbivory.



Such two-step echoes match ecological theory and show how evolutionary shifts in one part of an ecosystem can reverberate through others without direct contact.



<h2 class="wp-block-heading" id="h-species-evolve-across-communities">Species evolve across communities</h2>



Ecologists have long suspected that networks of interaction, not just pairwise encounters, shape evolution. 



Past research shows that even species that do not interact directly can drive traits to evolve across mutualistic networks.



Experiments with <a href="https://www.earth.com/news/guppies-are-helping-us-understand-evolution/">guppies</a> offered early proof that adaptation changes whole ecosystems, not only the fish themselves - locally adapted fish altered nutrient cycling, algae, and other organisms around them.



Daphnia add another layer to this picture. Far from being slow, they can respond to <a href="https://www.earth.com/news/its-a-two-way-street-between-evolution-and-environmental-change/" target="_blank" rel="noreferrer noopener">environmental change</a> within just a few generations, and their genetic shifts ripple through communities.



Modern genomics reveal how quickly Daphnia adapt to strong pressures, confirming that rapid evolution is not rare noise but a common feature of freshwater systems.



The study is published in <a href="https://www.pnas.org/doi/10.1073/pnas.2502742122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Species can evolve together without ever making contact

Evolution does not only respond to rivals, predators, or mates...

Low,Angle,View,Of,A,Group,Of,Multiracial,Young,Friends

Psychoactive drugs are often discussed in the context of risk, yet science keeps asking a different question. What do psychedelics teach us about how people connect, feel, and heal, and how can we study those effects carefully in humans?



Dr. Harriet de Wit, director of the Human Behavioral Pharmacology Laboratory at the <a href="https://psychiatry.uchicago.edu/" target="_blank" rel="noreferrer noopener">University of Chicago</a>, has spent her career building tools to answer those questions. 



She reflected on her work in a recent <a href="https://genomicpress.kglmeridian.com/view/journals/psychedelics/aop/article-10.61373-pp025k.0029/article-10.61373-pp025k.0029.xml?utm_source=chatgpt.com" target="_blank" rel="noreferrer noopener">interview</a>.



Two drugs sit at the center of the story, <a href="https://www.earth.com/news/psychedelic-drug-mdma-shows-promise-for-reducing-post-traumatic-stress/">MDMA</a> and <a href="https://www.earth.com/news/lsd-can-treat-crippling-anxiety-with-a-single-dose/">LSD</a>, because they shift internal states that standard lab tasks rarely capture.



<h2 class="wp-block-heading" id="h-studying-psychedelic-connections">Studying psychedelic connections</h2>



Dr. De Wit's work spans basic psychopharmacology and clinical translation, and her research program has been funded by the NIH for more than 42 years.



“The challenge of translating behavioral observations across species has continued to be a central theme in my research for the past 45 years,” said Dr. de Wit. 



She treats cross-species comparison as a tool to test which findings generalize and which do not.



Her path began with animal studies of drug taking, then moved into controlled trials with human volunteers. That shift opened the door to measuring self reported states that animals cannot convey.



She also insists on measuring both <a href="https://www.earth.com/news/study-shows-psilocybin-from-magic-mushrooms-delays-aging-and-significantly-extends-lifespan/">behavior</a> and self reporting. That approach allows human studies to capture experiences, like empathy or awe, that nonverbal animals cannot report.



<h2 class="wp-block-heading" id="h-psychedelics-connect-humans">Psychedelics connect humans</h2>



A controlled laboratory <a href="https://www.nature.com/articles/s41598-023-43156-0" target="_blank" rel="noreferrer noopener">study</a> found that single doses of MDMA increased how connected people felt to a stranger during a guided conversation. 



According to Dr. de Wit, demonstrating that MDMA enhances feelings of social connectedness during interpersonal interactions has profound implications for treating trauma-related disorders globally.&nbsp;



In the same paradigm, methamphetamine produced a similar rise in ratings of closeness, but only MDMA’s closeness was linked to oxytocin levels in saliva.



Those data put numbers on an everyday observation that pharmacology can shift social experience. The finding also gives therapists a concrete target, the feeling of connection during real conversations, to measure in future trials.



The work used a double blind, with separate groups for MDMA and methamphetamine. Participants rated closeness at the end of the session and one week later, providing both immediate and short follow-up readouts.



The similar behavioral outcomes with different physiological <a href="https://www.earth.com/news/one-psychedelic-dose-may-improve-brain-flexibility/">patterns</a> point to multiple routes to the same social endpoint. That matters because the mechanism will shape safety, dosing, and how a therapy session is structured.



<h2 class="wp-block-heading" id="h-lsd-and-mdma-microdosing">LSD and MDMA microdosing</h2>



A randomized, double blind <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9731343/" target="_blank" rel="noreferrer noopener">trial</a> in healthy adults tested four low doses of LSD given every few days and found modest, short-lived subjective effects without lasting changes in mood or cognition. 



Safety looked acceptable in that controlled setting, but the expected broad cognitive boost did not appear.



Across sessions, some acute effects weakened, suggesting that participants developed a tolerance for the low-dose LSD over time. 



The high microdose reduced feelings of rejection during a social exclusion task during dosing days, yet those changes did not persist at follow up.



“Drugs such as MDMA and low doses of LSD produce unusual alterations in self reported internal states, such as feelings of empathy, awe, and oneness with the environment,” said Dr. de Wit. 



Her research team now asks whether those altered states actually change future behavior, generosity, or values.



<h2 class="wp-block-heading" id="h-craving-can-rise-with-abstinence">Craving can rise with abstinence</h2>



A translational human <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC3027849/" target="_blank" rel="noreferrer noopener">study</a> in cigarette smokers documented incubation, the counterintuitive increase in cue triggered craving after longer abstinence periods. 



Across groups, cue-induced craving was greater after 35 days than after 7 days, even as background withdrawal eased.



The result pushes back against the idea that craving simply fades with time away from a drug. Clinicians can plan check-ins for later windows when cue reactivity rebounds, which may help people stay off cigarettes.



The design verified abstinence day by day and tested responses to smoking cues in a controlled setting. That level of control strengthens confidence that timing itself can shape craving <a href="https://www.earth.com/news/breathwork-creates-psychedelic-states-without-drugs/">responses</a>.



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



In a foundational human <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC2693956/" target="_blank" rel="noreferrer noopener">paper</a>, volunteers developed a conditioned place preference for a room paired with amphetamine, and their preference tracked how much they liked the drug during conditioning. 



The result validated a widely used animal assay in people and tied subjective liking to learned context.



Procedurally, the study used repeated conditioning sessions followed by a test day when people rated the rooms. That design allowed the team to connect learned preference to the specific feelings the drug produced during training.



<h2 class="wp-block-heading" id="h-feeling-connected-with-psychedelics">Feeling connected with psychedelics</h2>



A phase 3 <a href="https://www.nature.com/articles/s41591-023-02565-4" target="_blank" rel="noreferrer noopener">trial</a> reported that MDMA assisted therapy reduced symptom severity and functional impairment in people with moderate to severe PTSD. 



These clinical outcomes sit alongside lab-based evidence that MDMA can increase feelings of connection during real conversations.



Translation is never automatic, but it is not a shot in the dark. By pairing controlled human experiments with clinical trials, researchers can map which laboratory effects actually move the needle in care.



“I am concerned about the decline in respect for science, scholarship, and education,” said Harriet de Wit. A long running research program only exists when society is willing to invest in it.



The study is published in the journal <a href="https://genomicpress.kglmeridian.com/view/journals/psychedelics/aop/article-10.61373-pp025k.0029/article-10.61373-pp025k.0029.xml" target="_blank" rel="noreferrer noopener">Psychedelics</a>.



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How psychedelics enhance feelings of deep connection, even between strangers

Psychoactive drugs are often discussed in the context of risk,...

A new study maps the chemical cues that common gut bacteria detect, showing what helps them find nutrients and thrive. Researchers tested real human gut residents rather than the usual lab pathogens, and the results reset a few assumptions.



The experts found that carboxylic acids - especially lactic acid and formic acid - top the list of preferred cues in these microbes. The work was led by Victor Sourjik at the Max Planck Institute for Terrestrial Microbiology (<a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC11844446/" target="_blank" rel="noreferrer noopener">MPI</a>).



<h2 class="wp-block-heading" id="h-microbes-follow-chemical-trails">Microbes follow chemical trails</h2>



The microbiome is a bustling community where microbes trade byproducts and share resources. Cross-feeding is central to that economy, as a recent review showed with examples across the gut ecosystem.



Bacteria use chemotaxis to swim toward helpful chemicals and away from harmful ones. In Escherichia coli, a classic study linked stronger attraction to amino acids with faster use of those same amino acids.



Nutrients do not just feed an individual cell, they shape who lives where. Signals can set up gradients that guide <a href="https://www.earth.com/news/microbes-found-alive-sealed-inside-rock-after-2-billion-years/">microbes</a> toward niches that match how they make a living.



The new work asks a simple question with wide reach: What do helpful gut bacteria actually sense in the chemical soup of the intestine?



<h2 class="wp-block-heading" id="h-probing-gut-bacteria-detection">Probing gut bacteria detection</h2>



The researchers built a library of sensory domains from 20 gut species, focusing on the abundant Clostridia, then screened more than 150 metabolites.



They identified 34 matches between receptors and specific compounds, spanning amino acids, nucleobase derivatives, amines, indole, and several classes of carboxylic acids.



These sensory domains sit on three types of transmembrane receptors that control movement, gene responses, or second messengers. Ligands were assigned to 12 of 35 chemotaxis receptors but only one of 33 histidine kinase receptors, a pattern consistent with chemotaxis being mainly about finding food.



The coverage was deep for one large family of extracellular sensor modules called Cache domains. About half of the Cache-type chemotaxis receptors in the tested commensals could be assigned a ligand.



Those numbers matter because they connect behavior to metabolism. They show that in this habitat, receptors lean toward signals tied to growth.



<h2 class="wp-block-heading" id="h-what-bacteria-prefer-to-find">What bacteria prefer to find</h2>



Acids made up most of the results. Among them, <a href="https://www.earth.com/news/energy-can-be-generated-from-sweaty-fingertips/">lactate</a> and formate were the ones bacteria responded to the most.



That pattern fits what we know about community metabolism, where one microbe’s waste is another’s lunch. Microbial lactate utilization often funnels into energy-yielding pathways that stabilize the gut environment.



Growth tests in several Roseburia strains supported the idea that these cues point to food sources. L-lactate and formate accelerated growth most strongly in strains that carried matching receptors.



Microbes sensed the familiar short chain fatty acids (SCFAs) too, but less often than expected. The high-affinity sensors favored lower-abundance metabolites, showing how microbes home in on limiting resources.



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



A ligand is simply a chemical that a receptor can detect and respond to. In this study, researchers looked at two types of sensor designs: one with a single unit that picked up on lactate or pyruvate, and another with two units that could respond to very different types of molecules.



One of these two-unit sensors, called dCache_1UR, turned out to be especially interesting. One part of it recognized uracil, while the other part detected acetate. 



The team was even able to map out its structure, showing how each part used a different set of building blocks to grab onto its target.



That split setup hints at flexible wiring. The binding pocket that recognizes uracil is closely related to an amine-sensing pocket, and small sequence swaps can shift specificity.



Evolutionary analysis suggested that these domains change targets readily as bacteria adapt to new niches. That adaptability may explain how commensals tune their sensory repertoire to the gut’s complex chemistry.



<h2 class="wp-block-heading" id="h-bacteria-talks-to-each-other-and-us">Bacteria talks to each other and us</h2>



When one species secretes lactate or formate, neighbors with matching sensors can follow the trail. This creates channels for cross-feeding that keep communities resilient, even when diets or conditions shift.



Signals are not limited to nutrients. Microbiota-derived indoles modulate <a href="https://www.earth.com/news/even-mild-inflammation-can-majorly-damage-the-brain/">inflammation</a> and can reshape microbial networks through metabolite handoffs.



These findings land squarely in the lives of butyrate producers like Roseburia. Roseburia intestinalis is a motile, beneficial organism tied to barrier health and energy balance through butyrate production.



Chemotaxis gives such species a way to track nutrient gradients near the intestinal wall. It also offers a route to coordinate with partners that release the compounds they prefer to use.



<h2 class="wp-block-heading" id="h-nutrition-microbes-and-balance">Nutrition, microbes, and balance</h2>



If commensals chase lactate and formate, diet and host <a href="https://www.earth.com/news/human-metabolism-has-evolved-to-become-energetically-unique/">metabolism</a> could indirectly steer where and how these microbes grow. That opens the door to interventions that alter metabolite landscapes rather than trying to install single strains.



Therapies that stabilize lactate fluxes may help keep communities in balance. SCFA production could improve when lactate is quickly captured and converted by the right partners.



The receptor data point toward specific targets for prebiotics that enrich favorable behaviors. They also sketch a map for designing biosensors that report on gut chemistry in real time.



"These domains appear to be important for interactions between bacteria in the gut and could play a key role in the healthy human microbiome," said Wenhao Xu, a postdoctoral researcher in Sourjik’s group.



<h2 class="wp-block-heading" id="h-next-steps-in-gut-sensing">Next steps in gut sensing</h2>



The discovery of dual-module receptors that bind uracil and acetate raises questions about module cooperation. Independent binding means two inputs without crosstalk, yet evolution could rewire that logic.



Formate and lactate preferences appear widespread among chemotactic receptors in these commensals. Tracking how those preferences change with diet, medication, or disease would be informative.



The team found a sensor protein that detects indole, a chemical signal made by microbes. This shows how bacteria can link what they sense in their environment to changes in <a href="https://www.earth.com/news/some-genes-may-predict-infertility-and-disease-by-flipping-like-a-light-switch/">gene</a> activity. 



The researchers also noticed that receptor strength worked in the opposite way to how common each metabolite was. In other words, receptors bound most tightly to rare compounds - an advantage in patchy environments where resources are scarce.



The study is published in the journal <a href="https://www.pnas.org/doi/10.1073/pnas.2508950122" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Gut bacteria 'sniff out' nutrients with big effects on our health

A new study maps the chemical cues that common gut...

Life needs proteins for almost everything, from cell repair to immune defense. Scientists have long asked how the first proteins were formed before cells had complex machinery.



A new study reports a simple, water-friendly reaction that links early ingredients into the first steps toward protein-making. 



The project was led by Professor Matthew Powner at University College London (<a href="https://www.ucl.ac.uk/" target="_blank" rel="noreferrer noopener">UCL</a>), a chemist whose lab explores prebiotic chemistry.



"At life’s functional core, there is a complex and inseparable interplay between nucleic acids and proteins, but the origin of this relationship remains a mystery," wrote the researchers.



<h2 class="wp-block-heading" id="h-molecules-that-build-proteins">Molecules that build proteins</h2>



The team showed that RNA - a <a href="https://www.earth.com/news/new-discovery-water-molecules-will-force-chemistry-textbooks-to-be-rewritten/">molecule</a> that stores and transfers genetic information and can catalyze reactions - can become chemically linked to amino acids. These small molecules build proteins, and the linkage occurs under mild conditions in water.



The researchers changed amino acids into a more reactive form that holds extra energy, then linked those energized amino acids to RNA at a specific spot in the molecule, all without needing enzymes.



The reaction preferred the end of a double stranded RNA over interior positions, which avoids random chemistry that would scramble sequences. The experts also reported strong yields for several amino acids, including arginine linked to <a href="https://www.earth.com/news/forgotten-chemical-reactions-offer-clues-to-lifes-origins/">adenosine</a> at up to 76 percent.



<h2 class="wp-block-heading" id="h-sulfur-chemistry-drives-origins">Sulfur chemistry drives origins</h2>



A thiol is a sulfur-containing compound common in metabolism, and thioesters made from thiols power many reactions in modern cells. 



Using thioesters makes chemical sense for early Earth because they react in water without falling apart quickly, helping drive protein-related chemistry.



Earlier work from the same community showed that pantetheine, the active fragment of Coenzyme A that forms many biological thioesters today, can form under prebiotic conditions in water. That work supports the idea that the same types of sulfur chemistry existed before life began.



This new result connects that energy-rich chemistry to RNA handling of amino acids. It links metabolism- like reactions to information carriers, which is exactly the bridge origin of life research has needed.



<h2 class="wp-block-heading" id="h-molecules-found-in-all-living-cells">Molecules found in all living cells</h2>



The team uncovered a switch that controls two different steps. In step one, thioesters favor attaching the amino acid to RNA, creating aminoacyl RNA in water at neutral pH. 



In step two, converting to thioacids and adding a mild oxidant pushed peptide bond formation, which produced peptidyl RNA in very high yields.



Peptides are short chains of amino acids, usually two to 50 units long, while larger folded chains are proteins. Making peptidyl RNA shows that RNA-bound amino acids can be extended into short chains, a necessary move toward protein-like function.



“What is groundbreaking is that the activated amino acid used in this study is a thioester, a type of molecule made from <a href="https://www.earth.com/news/key-compound-suggests-that-life-beyond-earth-could-be-common/">Coenzyme A</a>, a chemical found in all living cells," said Dr. Jyoti Singh of UCL Chemistry. "This discovery could potentially link metabolism, the genetic code, and protein building,”



<h2 class="wp-block-heading" id="h-neutral-waters-spark-proteins">Neutral waters spark proteins</h2>



The chemistry works in water at near neutral pH, which points to pools, lakes, or wet shorelines rather than the open ocean. Concentrations would have been higher in small bodies of water, and minerals could have helped organize the molecules.



Freeze concentrate cycles also help. The researchers observed effective aminoacylation under eutectic ice conditions near 19°F. In this environment, ice excludes salt and concentrates solutes into brines, which speed reactions without harsh reagents.



“It seems pretty probable that this reaction would have been occurring on early Earth,” said Professor Powner. That assessment reflects the mild requirements and the water compatibility of the chemistry.



<h2 class="wp-block-heading" id="h-bridging-chemistry-and-biology">Bridging chemistry and biology</h2>



Modern cells make proteins with the ribosome, a ribonucleoprotein machine that reads messenger RNA and couples amino acids with the help of transfer RNAs. 



The new chemistry provides a path for RNA to handle amino acids without proteins, easing the chicken or egg problem.



An earlier study proposed an <a href="https://www.earth.com/news/rna-breakthrough-sheds-light-on-the-beginning-of-life/">RNA</a> peptide world in which RNA and short peptides co-evolved, forming chimeric molecules that could grow and select function. The present result shows a plausible way for RNA to acquire and extend amino acids in water.



<h2 class="wp-block-heading" id="h-the-modern-genetic-code">The modern genetic code</h2>



The genetic code is the set of rules that maps RNA triplets to amino acids. By preferring attachment at RNA termini and operating under duplex control, this chemistry hints at how sequence specific pairing could later become coded instruction.



The researchers point to the need for sequence preferences that pair specific RNA sequences with specific <a href="https://www.earth.com/news/lifes-building-blocks-may-have-formed-near-newborn-stars-and-planets/">amino acids</a>. That would move from chemistry that charges RNA to chemistry that begins to encode.



Success there would show how early RNA could use simple rules to shape peptide sequences, with later evolution building the fully fledged ribosome and the modern code.



The study is published in the journal <a href="https://www.nature.com/articles/s41586-025-09388-y" target="_blank" rel="noreferrer noopener">Nature</a>.



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How Earth’s first proteins may have formed in water

Life needs proteins for almost everything, from cell repair to...

As night falls in the rainforests, orangutans climb into the canopy to construct intricate tree nests, displaying remarkable ingenuity. 



These comfy platforms are carefully engineered beds, providing warmth, comfort, protection from predators, and even reduce mosquito bites.



Scientists have long wondered how young orangutans learn to master such complex architecture. Recent findings reveal that they acquire this skill through close observation and practice, a process called observational <a href="https://www.earth.com/news/chimpanzees-and-bees-are-capable-of-complex-social-learning/">social learning</a>.



<h2 class="wp-block-heading" id="h-orangutans-build-nests-for-survival">Orangutans build nests for survival</h2>



Nest-building is essential for survival. Unlike many behaviors in <a href="https://www.earth.com/news/what-orangutans-can-teach-humans-about-food-and-fitness/">animals</a>, this skill is neither entirely instinctive nor quickly learned. 



Orangutans must manipulate branches, twigs, and leaves with strength and dexterity while making decisions about materials and structure.



Night nests, far more elaborate than day nests, can include linings, pillows, blankets, and even roofs. 



To build such structures requires both technical know-how and material knowledge, making nest-building a cognitively demanding task.



Young <a href="https://www.earth.com/news/orangutan-mothers-have-unique-parenting-styles-like-humans/">orangutans</a> begin showing interest in nests at just six months, playing with leaves and branches. 



Practice of basic day nests starts around age one, but night nest practice begins only at three years and is not mastered until about the age of eight.



Complex additions, such as multitree nests and comfort elements, appear later. This long timeline shows that the skill is not acquired quickly but gradually, with repeated attempts and guided observation.



<h2 class="wp-block-heading" id="h-learning-from-mom">Learning from mom</h2>



Researchers documented that immatures who carefully peered at their mothers during nest-building were far more likely to practice soon afterward. 



Merely being nearby without watching closely did not have the same effect. This highlights the importance of selective attention in learning.



“Nest-building is critical to <a href="https://www.earth.com/news/experts-unlock-the-mysteries-of-orangutan-communication/">survival</a> in orangutans but is surprisingly not the focus of a lot of research," noted Dr. Ani Permana from the <a href="https://warwick.ac.uk" target="_blank" rel="noreferrer noopener">University of Warwick</a>. 



"We previously reported that it takes multiple years for immature orangutans to learn to nest-build but, based on 17 years of observational data, this paper shows that this learning process is highly dependent on young animals carefully watching the nest-building of others.”



<h2 class="wp-block-heading" id="h-orangutan-nests-are-complex">Orangutan nests are complex</h2>



The study also showed that young orangutans pay special attention to complex features like multitree nests, twig manipulations, and comfort elements. 



These require memorizing multiple steps and sequences. After observing these, immatures increased their practice, suggesting they were specifically learning the more challenging parts. 



Simpler nests, such as single-tree day nests, did not trigger the same level of focused observation.



“Orangutan nest-building tendency may have some innate basis, but the details and method must be socially learned, starting from a very young age, by watching and practicing, learning from mistakes as they grow and this paper is the first time this has been shown in wild apes,” Dr. Permana added.



At first, immatures mostly learn from their mothers, but as they grow older, they begin peering at other group members, thereby expanding their knowledge base.



<h2 class="wp-block-heading" id="h-learning-what-to-use">Learning what to use</h2>



Beyond construction skills, orangutans also learn what materials to use. 



“Aside from learning ‘how to’ build a nest, immature orangutans also appear to learn the ‘know-what’ of which materials to use," noted Dr. Caroline Schuppli, <a href="https://www.ab.mpg.de/" target="_blank" rel="noreferrer noopener">Max Planck Institute of Animal Behavior</a>.



The choice of tree species is important, and infants - who primarily peer at their mothers - are more likely to select the same species their mothers use.



“Just like human teenagers finding their own path, maturing orangutans increasingly peer at the nest-building of others and begin experimenting with the tree species those individuals use," Dr. Schuppli continued.



<h2 class="wp-block-heading" id="h-returning-to-roots">Returning to roots</h2>



Interestingly, adults often revert to using the tree species favored by their mothers, even after experimenting with alternatives in youth.



“Ultimately, adult orangutans tend to revert to the nest materials used by their mothers, perhaps recognizing that the most effective methods had already been established," Dr. Schuppli noted. 



"This consistent variation in nest materials across generations indicates that wild orangutan populations possess cultural elements that could be lost without the conservation of the species and their habitats,” 



<h2 class="wp-block-heading" id="h-orangutans-learn-and-pass-on-traditions">Orangutans learn and pass on traditions</h2>



The study emphasized four main points: peering, not just proximity, drives learning; immatures focus on complex multi-step elements; role models expand with age; and knowledge of tree species is socially transmitted.



These findings suggest orangutans display cultural variation, with nest-building traditions passed through generations.



<a href="https://academic.oup.com/book/32658/chapter-abstract/270606055?redirectedFrom=fulltext&amp;login=false" target="_blank" rel="noreferrer noopener">Nest-building</a> is an evolutionarily ancient behavior shared by great apes. 



By proving that orangutans acquire this skill through observational social learning, the study suggests that such cultural learning has deep roots in primate history.



It highlights not just the intelligence of orangutans but also their fragile cultural heritage - one that can only continue if their forest homes are preserved.



The study is published in the journal <a href="https://www.nature.com/articles/s42003-025-08217-2" target="_blank" rel="noreferrer noopener">Communications Biology</a>.



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Orangutans learn to build complex tree nests by watching their mothers

As night falls in the rainforests, orangutans climb into the...

The universe feels simple at first glance: stars, gas, dust, and the gravity that binds it all. Then you look more closely and realize that nothing could be farther from the truth. 



For decades, the standard picture has said that most of what is out there is not what we can see. It is a mix of ordinary matter and two invisible components often called dark matter and dark energy.



That picture has guided textbooks, space missions, and how we read the sky. It has also raised tough questions that have never quite gone away, mainly because of the fact that dark matter and <a href="https://www.earth.com/news/is-dark-energy-changing-the-mystery-of-cosmic-expansion-deepens/">dark energy</a> have never actually been "seen."



<h2 class="wp-block-heading" id="h-challenging-dark-matter-s-existence">Challenging dark matter's existence</h2>



A new line of thinking takes those questions seriously and suggests we may not need those "dark" invisible components after all.



After years spent probing longstanding cosmology puzzles, physics professor <a href="https://www.uottawa.ca/faculty-science/professors/rajendra-gupta" target="_blank" rel="noreferrer noopener">Rajendra Gupta</a> has proposed a model that aims to explain the universe without dark matter or dark energy. 



Gupta teaches astrophysics at the <a href="https://www.uottawa.ca/en" target="_blank" rel="noreferrer noopener">University of Ottawa</a> and argues that familiar assumptions might be impeding progress.



"The study's findings confirm that our <a href="https://academic.oup.com/mnras/article/524/3/3385/7221343?login=false" target="_blank" rel="noreferrer noopener">previous work</a> ("JWST early universe observations and ΛCDM cosmology") about the age of the universe being 26.7 billion years has allowed us to discover that the universe does not require dark matter to exist," explains Gupta.



<h2 class="wp-block-heading" id="h-tired-light-and-the-ccc-theory">"Tired light" and the CCC theory</h2>



Gupta’s approach blends two concepts: covarying coupling constants (<a href="https://ui.adsabs.harvard.edu/abs/2023Univ....9...70G/abstract" target="_blank" rel="noreferrer noopener">CCC</a>) and "tired light" (<a href="https://en.wikipedia.org/wiki/Tired_light" target="_blank" rel="noreferrer noopener">TL</a>). 



CCC asks whether the so-called constants of nature - like the strength of forces or the <a href="https://www.earth.com/news/dark-matter-may-consist-of-particles-that-travel-faster-than-light/">speed of light</a> - might shift across time or space. If they do, even slightly, many calculations about how the universe evolves would change.



TL offers a different take on why light from faraway galaxies appears redshifted. Instead of treating redshift solely as a sign of cosmic expansion stretching light, TL suggests that photons shed energy over vast distances, shifting their color toward red. 



Taken together, the CCC+TL model seeks to account for cosmic signals.



<h2 class="wp-block-heading" id="h-most-scientists-think-dark-matter-is-real">Most scientists think dark matter is real</h2>



The idea of dark matter did not arise in a vacuum. In the 1930s, astronomer <a href="https://en.wikipedia.org/wiki/Fritz_Zwicky" target="_blank" rel="noreferrer noopener">Fritz Zwicky</a> noticed that galaxy clusters seemed to move in ways that did not match their visible mass. 



Later, astronomers saw that many galaxies rotate faster than expected at their outskirts. Something appears to add extra gravity. <a href="https://www.earth.com/news/einstein-ring-discovered-normal-galaxy-ngc-6505-gravitational-lens/">Gravitational lensing</a> - the way mass bends light - also points to more pull than starlight alone can explain.



In the standard breakdown, dark matter is thought to make up about 27% of the universe. Ordinary matter - everything we can directly detect - adds up to less than 5%. 



The rest is labeled <a href="https://www.earth.com/news/universe-expansion-rate-dark-energy-measured-11-billion-years-ago/">dark energy</a>, a placeholder for whatever drives the universe’s accelerated expansion. This picture also includes a commonly accepted age of roughly 13.8 billion years.



<h2 class="wp-block-heading" id="h-questioning-the-need-for-dark-matter">Questioning the need for dark matter</h2>



Gupta contends that if the forces of nature weaken over time, we do not need dark energy to explain why the expansion appears to speed up. 



He also argues that major observations can be matched without dark matter by allowing constants to vary and by letting light lose a small amount of energy as it travels long distances to reach us, the observers.



"Contrary to standard cosmological theories where the <a href="https://science.nasa.gov/dark-energy/" target="_blank" rel="noreferrer noopener">accelerated expansion</a> of the universe is attributed to dark energy, our findings indicate that this expansion is due to the weakening forces of nature, not dark energy," Gupta continues.



<h2 class="wp-block-heading" id="h-redshifts-and-cosmic-observations">Redshifts and cosmic observations</h2>



A substantial part of the work centers on <a href="https://www.esa.int/Science_Exploration/Space_Science/What_is_red_shift" target="_blank" rel="noreferrer noopener">redshifts</a> - how light shifts toward longer wavelengths as it travels. 



The analysis compares how galaxies are distributed at low redshift with patterns from the early universe at high redshift. 



The claim is that these signals align under the <a href="https://arxiv.org/abs/2508.04277" target="_blank" rel="noreferrer noopener">CCC+TL approach</a> without requiring dark matter in the equations.



"There are several papers that question the existence of dark matter, but mine is the first one, to my knowledge, that eliminates its cosmological existence while being consistent with key cosmological observations that we have had time to confirm," Gupta confidently concludes.



<h2 class="wp-block-heading" id="h-what-does-all-of-this-mean">What does all of this mean?</h2>



If CCC+TL continues to pass tests, much would change. The model would offer new routes to explain the <a href="https://www.earth.com/news/ground-based-telescopes-detect-light-from-the-cosmic-dawn/">cosmic microwave background</a>, the timeline of how galaxies formed and grew, and the way light bends on its journey to our telescopes. 



It would also change how we read distance and time from the sky, since redshift would no longer be only a ruler for expansion.



It would challenge the Big Bang–anchored timeline. Those are substantial claims that require careful tests.



<h2 class="wp-block-heading" id="h-testing-gupta-s-theory">Testing Gupta’s theory</h2>



Specific predictions need to be articulated. Any model has to meet observations head-on: galaxy rotation profiles, lensing maps, the pattern of hot and cold spots in the <a href="https://www.earth.com/news/scientists-capture-baby-pictures-of-the-very-early-universe-cosmic-microwave-background/">microwave background</a>, and the way <a href="https://www.earth.com/news/largest-cosmic-particle-cloud-ever-found-has-stunned-astronomers/">galaxies cluster</a> across hundreds of millions of light-years. 



If constants vary, even a little, that could leave signatures in atomic spectra from distant quasars. If light tires, the effect should be measurable with enough precision and a clean way to separate it from other causes.



Teams are already poring over deep-sky surveys, precise supernova samples, and high-resolution microwave maps. 



As instruments improve, the bar for any alternative rises. The goal is straightforward: make a clear, testable forecast, then see if the universe agrees.



<h2 class="wp-block-heading" id="h-dark-matter-ccc-tl-and-next-steps">Dark matter, CCC+TL, and next steps</h2>



Two central questions remain. Are dark energy and dark matter just bookkeeping devices we used while working with fixed constants and a single redshift story? Could the true age of the universe be significantly older than the standard estimate? 



The only way to answer is to press for independent tests that can separate one picture from the other.



Researchers are tuning methods to compare models fairly, using the same data pipelines and error checks. That helps avoid apples-to-oranges results. 



If CCC+TL keeps matching the sky, interest will grow. If it stumbles on a key observation, that will be clear too.



Cosmology moves forward when claims meet data. This study advances a bold alternative: a universe where constants can change, light can lose energy across great distances, and neither dark matter nor dark energy need to be included in the ledger. 



It offers clear, testable statements about cosmic age and the cause of the apparent acceleration.



The work will be validated or refuted by measurements. That is how the field operates: no shortcuts, no hand-waving - only observations and models that either fit or fail.



The full study was published in <a href="https://iopscience.iop.org/article/10.3847/1538-4357/ad1bc6" target="_blank" rel="noreferrer noopener">The Astrophysical Journal</a>.



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Study claims dark matter does not exist and the universe is 27 billion years old

The universe feels simple at first glance: stars, gas, dust,...

An international team kept solid gold intact while superheating it to 19,000 Kelvin, about 33,740 °F (18,726 °C). They measured the temperature directly, in real time, and documented the feat in a new study. The result outstrips a long assumed ceiling on how hot a solid can get before it gives way.



The team reached this state with ultra fast laser heating and then checked the atoms with precise X-ray probes.



The work also lays out a clean way to take the temperature of extremely hot, dense matter, which is something that has frustrated experimenters for decades.



<h2 class="wp-block-heading" id="h-what-superheating-gold-means">What superheating gold means</h2>



Lead author Thomas G. White of the University of Nevada, Reno (<a href="https://www.unr.edu/physics/people/admin-faculty-and-staff/thomas-white" target="_blank" rel="noreferrer noopener">UNR</a>), led the international collaboration with colleagues at SLAC National Accelerator Laboratory and partner institutions.



The study focuses on superheating, which is when a solid sits above its melting point yet does not melt because the rapid conditions do not give its structure time to reorganize.



Here, the group pushed a <a href="https://www.earth.com/news/new-high-grade-gold-mine-found-in-an-unexplored-area-of-south-america/">thin gold sample</a> far beyond its normal melting threshold in a flash. 



The superheated gold remained crystalline for a brief window, long enough to record how fast the atoms were moving and therefore how hot the lattice was.



The work touches a broader frontier known as warm dense matter (WDM), which is a high energy state relevant to planetary interiors and fusion targets.



Accurate temperatures in this regime have been hard to pin down because these hot states are tiny and very short lived.



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



In 1988, Hans J. Fecht and William L. Johnson proposed an upper stability boundary called the <a href="https://www.nature.com/articles/334050a0" target="_blank" rel="noreferrer noopener">entropy catastrophe</a>, arguing that a solid cannot be heated much past about three times its melting temperature without melting. 



The idea was that as a crystal heats, its entropy rises until it matches the liquid, which should trigger melting.



That back of the envelope limit, about three times the melting point, became the accepted stopping point in textbooks and talks. 



It also aligned with the fact that most experiments ran into disordering events at lower temperatures anyway.



The new gold measurements show that ultra fast heating sidesteps those assumptions. 



By outrunning processes that normally give a <a href="https://www.earth.com/news/scientists-create-a-time-crystal-using-giant-atoms-long-thought-to-be-impossible/">crystal time to expand</a> and unravel, the team produced a much hotter solid phase without violating basic physics.



<h2 class="wp-block-heading" id="h-how-the-team-pushed-past-the-limit">How the team pushed past the limit</h2>



The experiment used a brief pulse, only 45 femtoseconds long, to pump energy into a thin gold <a href="https://www.earth.com/news/new-silver-and-gold-discovery-morena-confirmed-to-be-extraordinarily-high-grade-deposits/">foil</a>.



Immediately after this, an intense X-ray pulse captured the atomic motion through tiny shifts in the scattered X-ray frequency. This gave a direct readout of the atoms’ speeds.



Those shifts revealed the gold’s lattice temperature without relying on indirect models. 



Because the heating was so swift, the lattice could not expand significantly during the measurement window, and crystalline order persisted for a few trillionths of a second.



The diagnostic hinges on inelastic X-ray scattering (<a href="https://neutrons.ornl.gov/sites/default/files/NX2023_IXS.pdf" target="_blank" rel="noreferrer noopener">IXS</a>) which, in this fast backscattering geometry, records a clean spectral broadening linked to atomic velocities.



In short bursts, the technique treats the ion motion much like a classical gas and translates the line width into temperature.



<h2 class="wp-block-heading" id="h-obeying-the-laws-of-thermodynamics">Obeying the laws of thermodynamics</h2>



Direct temperature tracking matters because warm dense matter only exists for fleeting instants in the lab. 



A reliable, model independent measurement gives planetary physicists and fusion researchers a sharper tool to test their calculations.



“It is important to clarify that we did not violate the <a href="https://www.sciencedirect.com/topics/chemistry/second-law-of-thermodynamics" target="_blank" rel="noreferrer noopener">Second Law of Thermodynamics</a>. [But] the entropy catastrophe was still viewed as the ultimate boundary,” said White.



Outside voices have noted that ultrafast, ultrasmall conditions may not map cleanly onto everyday solids under normal pressure. 



Even so, this controlled window lets researchers test long-standing assumptions about melting and stability with far less guesswork.



<h2 class="wp-block-heading" id="h-heating-gold-for-future-technology">Heating gold for future technology</h2>



Better temperature measurements open doors for modeling planets, where WDM controls how heat moves through cores and mantles. Getting the <a href="https://www.earth.com/news/superconductivity-achieved-at-room-temperature-with-new-materials/">temperature</a> right helps set the melting curves that guide those models.



Fusion research also stands to gain. In inertial confinement experiments, laser driven targets quickly cross from solid to ultra hot states, and design choices depend on when and how those transitions occur.



There is a materials angle as well. If rapid heating can lift other solids far beyond past expectations without immediate melting, that would invite a rethink of strength, heat capacity, and failure in extreme environments.



The upshot is not that thermodynamics has been tossed out. It is that speed, and the lack of time for expansion, can keep order in place long enough to measure and learn from it.



Future work will likely try different elements, thicker targets, and varied time delays to map exactly when order fails. Each variation will test where the practical limits really lie and how general the no-longer-so- strict ceiling might be.



The full study is published in the journal <a href="https://www.nature.com/articles/s41586-025-09253-y" target="_blank" rel="noreferrer noopener">Nature</a>.



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Physicists superheat gold to over 33,740°F without melting it

An international team kept solid gold intact while superheating it...

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