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Treefrog ‘fingerprints’ are on their eyeballs

Our fingerprints, patterns on whale flukes, and fur patterns on cheetahs are examples of the natural ways we can tell one individual animal from another. For an Amazonian treefrog called the egg-eating spiny-backed frog (Osteocephalus oophagus), we need to look into their eyeballs. Fine black radial lines cross their golden irises, and form a pattern similar to our fingerprints. A study recently published in the journal Herpetozoa details the discovery.

The project began with study co-author Mélissa Peignier, a behavioral ecologist at the University of Bern in Switzerland, admiring frog eyes. 

“At the time, I was doing my PhD, studying Allobates femoralis in the field in French Guiana,” Peignier said in a statement. “My first reaction was simply something along the lines of, ‘Wow, what beautiful eyes!’ That initial curiosity gradually turned into a genuine interest in the species, and I realised how little we actually know about them.”

a green frog sitting on a leaf
Osteocephalus oophagus in situ. Photographed in French Guiana (4°02’N, 52°41’W; ) between March and May 2021. Image: Mélissa Peignier et al., 2026.

There was also an ethical component. One of the standard ways to tell amphibians apart from one another is toe-clipping, where a section or all of a single toe is removed. This procedure can affect their survival, physiology, and behavior. 

“Other studies have used toe-clipping, which involves removing some of the digits. Personally, I was uncomfortable with this approach, especially given that these are arboreal frogs that rely on their limbs to climb trees.”

a green frog on a stone
Osteocephalus oophagus in situ. Photographed in French Guiana (4°02’N, 52°41’W; ) between March and May 2021. Image: Mélissa Peignier et al., 2026.

Looking for other markings could offer a more humane solution and a way to observe the animals natural behavior unimpeded.

For this study, fieldwork took place over three rainy seasons (2021 to 2023) on a river island in the Nouragues Nature Reserve in French Guiana. They identified 103 individual frogs over the course of the study.

Example of the diversity of iris patterns from eight Osteocephalus oophagus individuals photographed in French Guiana (4°02’N, 52°41’W; Bongers et al. 2001) between March and May 2021, 2022, and 2023. Image: Mélissa Peignier et al., 2026.
Example of the diversity of iris patterns from eight Osteocephalus oophagus individuals photographed in French Guiana (4°02’N, 52°41’W; Bongers et al. 2001) between March and May 2021, 2022, and 2023. Image: Mélissa Peignier et al., 2026.

During their later encounters, the team took pictures of each animal’s eyes without touching it and then compared the images with a reference library. This way, the recognised frogs were left undisturbed and their eyes appeared in their more natural state. The identifications were then independently verified using Wild-ID, a software package that analyzes photographic markings in animals.

They found highly distinctive iris patterns. Within one season, between 56 and 80 percent of the frogs were recaptured and reliably re-identified. According to the team, this indicates that the patterns on their eyes remain stable enough to monitor the frog in the short-term. Photographs could even be taken of frogs while in their mating embrace (called amplexus) without disrupting them. The team hopes that this method will spread. 

two frogs with one on top of the other's back
Osteocephalus oophagus in situ. Photographed in French Guiana (4°02’N, 52°41’W; ) between March and May 2021. These frogs are in amplexus, or their mating embrace. Image: Mélissa Peignier et al., 2026.

“In a world where biodiversity is declining at an alarming rate, it is essential that we minimise our impact on the animals we study,” added Peignier. “If we can reliably identify individuals using naturally occurring features, we may be able to reduce the need for more invasive marking techniques while still collecting the data needed to answer important scientific questions.”

While the reliability of the eye markings will vary between species, and should be done case by case, the team sees considerable promise for amphibians with complex irises. And working with them offers its own benefits. 

“Honestly, the frogs themselves are incredibly beautiful and surprisingly chill, which makes working with them a real pleasure,” Peignier said. 

The post Treefrog ‘fingerprints’ are on their eyeballs appeared first on Popular Science.

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What night is van Gogh’s ‘The Starry Night’? New analysis says it’s in July.

The swirling bluish-white mistrals, towering cypress trees, and glittery stars in Vincent van Gogh’s “The Starry Night” (1889) have captivated our imaginations for generations. Despite never selling a painting during his lifetime, van Gogh’s “The Starry Night” has since inspired a hit song in 1972, draws visitors to the Museum of Modern Art in New York City, and adorns everything from journals to scarves and tote bags.

But what particular night above Saint-Rémy-de-Provence, France, did the troubled post-impressionist painter actually put on the canvas? A new analysis points to July 22, 1889. During the early morning hours at that time of year, a waning crescent moon, the planet Venus, and the Hyades star cluster in Taurus appeared close together—all of which are seen in the painting. A study published today in the journal Scientific Reports details the findings. 

The story behind ‘The Starry Night’

According to the Metropolitan Museum of Art, van Gogh was inspired by the view from his window at the Saint-Paul-de-Mausole asylum in southern France. He spent twelve months there 1889–1890, seeking reprieve from his mental illnesses and was also diagnosed with a form of epilepsy. 

Like many of his paintings that year, “The Starry Night” was created in several sessions during the day, under different weather conditions. The village nestled below the hills was also based on other views, and could not be seen from his window. Although van Gogh reconstructed some of the features in the night sky as he saw them, he also altered the celestial shapes and added a sense of glow.

“Van Gogh assigned an emotional language to night and nature that took them far from their actual appearances,” the museum writes. “Dominated by vivid blues and yellows applied with gestural verve and immediacy, ‘The Starry Night’ also demonstrates how inseparable van Gogh’s vision was from the new procedures of painting he had devised, in which color and paint describe a world outside the artwork even as they telegraph their own status as, merely, color and paint.”

Looking to the stars

Using astronomy to pinpoint which day inspired the painting began with UCLA art historian Albert Boime in 1984 and Harvard University astronomer and astrophysicist Charles Whitney in 1986. The two scholars reached conflicting conclusions, and neither of them displaced the prevailing religious and symbolic interpretations of the painting. 

Historically, the painting has been dated based on a letter van Gogh wrote to his brother Theo around June 18, 1889. However, the waning gibbous moon from mid-June does not account for the slender crescent seen in the painting. By July 22, 1889, the Hyades star cluster rose in the eastern sky alongside Venus, and the moon’s shape looked closer to the crescent on the canvas. This new study uses observational geometry to find an answer.

“To an observational astronomer, the cluster of stars in ‘The Starry Night’ is the Hyades in Taurus,” said study co-author Elijah Jeong-hyun Kim.  “But the moment I read the earlier studies explaining it as Aries, I heard the painting calling to me.” Kim is the CEO at South Korean robotic telescope company SLLAB and a PhD candidate at Kyung Hee University.

For this research, the team combined astronomical simulations and measurements of star positions, with historical weather records, and van Gogh’s own letters. They also used earlier sketches of the landscape to reconstruct the narrow field of view represented in “The Starry Night.”

(A) The central cluster of stars in “The Starry Night” (1889), left, and the Hyades cluster in Taurus, center. At right, the five stars in the painting (orange) are overlaid on the real stars (blue) after matching for size, orientation and position; red dashed lines show the residual differences. (B) The stars in “Café Terrace at Night” (1888), left, and the stars around the Summer Triangle, center. The panel at right follows the same layout as in (A). Image: Kim et al., Scientific Reports (2026), Figs. 2, 4 and S1.
(A) The central cluster of stars in “The Starry Night” (1889), left, and the Hyades cluster in Taurus, center. At right, the five stars in the painting (orange) are overlaid on the real stars (blue) after matching for size, orientation and position; red dashed lines show the residual differences. (B) The stars in “Café Terrace at Night” (1888), left, and the stars around the Summer Triangle, center. The panel at right follows the same layout as in (A). Image: Kim et al., Scientific Reports (2026), Figs. 2, 4 and S1.

According to the team, the crescent moon, Venus, and the Hyades star cluster in the constellation Taurus would have been visible around dawn on July 22, 1889. This configuration generally corresponds to what is portrayed in the painting. Weather records suggest that the night sky around July 22 would have been clear enough for this astronomical arrangement to be visible. Additionally, the frequent mentions of cicadas in van Gogh’s letters suggest that the region was seeing a period of hot weather, which matches the recorded temperatures in July 1889 better than in June.

The team also verified that the painter’s field of view in another painting titled “Starry Night over the Rhône” (1888) with photographs taken on site was painted when the sky was in Aries. Using the same method, the team also believes that the stars in “Café Terrace at Night” (1888) may be the Summer Triangle.

“I hope this work prompts a renewed, multidisciplinary look at the sequence and working methods of the Saint-Rémy paintings, and at Van Gogh’s movements that summer,” Kim said. “Our conversation with Van Gogh’s other skies is still ongoing. We plan to tell those stories one by one.”

The post What night is van Gogh’s ‘The Starry Night’? New analysis says it’s in July. appeared first on Popular Science.

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Baby manta rays stick to the shallows to avoid sharks and orca

Before giant manta rays (Mobula birostris) can grow to up to 30 feet long and 4,409 pounds, they must start small like most living things. Giant manta ray babies (called pups) in Central America don’t have their size to protect them from orca whales (Orcinus orca) and the numerous sharks in the open ocean. Their solution—sticking to the coast, where there is plenty of food to help them grow and defend themselves. A new study published today in the journal Frontiers in Fish Science details the baby rays’ behavior. 

“We show that manta rays’ lifestyle isn’t a one-size-fits-all behavior. Giant manta rays in Central America undergo a dramatic shift in space use as they mature,” Jeffry Madrigal-Mesén, a study co-author and project leader of Mantas Costa Rica, said in a statement. “Juveniles remained strictly within shallow nearshore waters that serve as coastal refuges, but most of the tracked adults executed long-distance transboundary migrations along the continental shelf break into Central America.”

a manta ray swimming
Puntitos, one of the immature mantas the scientists followed. Image: Jeffry Madrigal.

Where the pups grow

In the study, the team used multiple methods to track and identify mantas at five locations between 2018 and 2025. Acoustic telemetry uses underwater sound pulses to monitor fish movements and allowed the team to track 59 individual rays. With satellite telemetry, transmitters track movement and behavior from a distance and helped the team track large-scale movements of 12 individuals. Lastly, photo identification helped to identify individual manta rays.

“If we hadn’t used all three technologies together, we simply wouldn’t have been able to piece this puzzle together,” explained Madrigal-Mesén. “Combining these tools turned fragmented data into a unified, undeniable story.”

The team ended up with a dataset of over 12,000 detections. The data showed that young mantas (those with a body about 10 feet or less) stick to shallow coastal refuges. In these more shallow spots, the pups have a safe place that doesn’t overlap with their predators’ hunting grounds. They have plenty of food and places to hide, and even get essential services like cleaning from reefs.

“Mature adults can rely on their massive body size and their ability to dive deep to evade threats. But juveniles don’t have that luxury,” said Madrigal-Mesén. “What is truly amazing is seeing how strictly young manta rays stick to coastal waters as long-term refuges. We see the same individuals more often than once a year. In fact, just recently, they were sighted again at the exact same tagging location. It is always a joy to see them again—they have truly become a part of the family.”

a manta ray swimming by a diver
Manta ray in close proximity to a diver. Image: Jeffry Madrigal.

By comparison, nine mature mantas in the study went on expansive migrations along the continental shelf break. One manta ray nicknamed Mickey Mouse because of a spot pattern on his belly had movements that suggest the fish also continue to display loyalty to a particular site once they grow up. Unusually approachable for a manta, Mickey Mouse allowed the team tag him multiple times over several years, which provided a continuous dataset. In 2020, he logged 462 acoustic detections at a coastal hub called El Secreto. He returned to the same shelf in 2023, and stayed there for 38 days.

“Nearshore cleaning stations transcend basic hygienic function; they act as primary social hubs where courtship and reproductive interactions take place,” said Madrigal-Mesén. “Returning to a predictable coastal depot allows mature rays to prioritize social and cleaning needs before undertaking large-scale regional migrations.”

Traveling the manta swimway—safely

Once they leave coastal regions, adult manta rays face different dangers. Coastal areas are often legally protected marine reserves, but the open ocean is another story. They no longer have legal protection and are exposed to dangers from industrial fisheries and vessel strikes.

According to the team, this shows that marine protected areas alone are not enough to protect this highly mobile species as it swims across Central America. They say that multi-national “conservation swimways”  that link the domestic juvenile coastal refuges with adult migratory corridors could help keep the endangered rays safe. 

“This study opens a new chapter for manta ray research in Central America,” Madrigal-Mesén concluded. “We hope it sparks fresh enthusiasm and encourages future collaborators to join us in executing the new ideas and research projects we have planned for the conservation of this species.”

The post Baby manta rays stick to the shallows to avoid sharks and orca appeared first on Popular Science.

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Monkeys also avoid germs after viral outbreaks 

When a new disease emerges, things can get a little weird. We start to clean groceries with antibacterial wipes, the sound of a sneeze can trigger our fight-or-flight response, and we generally become more cautious. Humans may not be the only primate species that change their behavior in the face of disease. 

According to a study published today in the journal Royal Society Open Science, Japanese macaques (Macaca fuscata) that lived through a deadly outbreak in 2020 became noticeably more cautious about food that appeared contaminated, even though this disease was not spread by food or feces. This indicates that purposefully shifting behavior to avoid a pathogen can be shaped by our appearance and that disgust may have deep evolutionary roots. It also sheds light on the behavioral immune system—a collection of behaviors that help animals avoid an infection before the biological immune systems respond.

“We can show now, in non-human primates, that this is the same for them,” Federico Rossano, a study co-author and cognitive psychologist at the University of California San Diego, said in a statement. “Even with no knowledge of how disease is transmitted, being exposed to others getting sick and dying changes the likelihood of engaging in behaviors that potentially could lead to some form of sickness.”

2020 was a big year for outbreaks

In 2020, the staff at a primate sanctuary in southern Texas confirmed the presence of simian retrovirus Type II. This disease can cause AIDS-like immunodeficiency and is primarily transmitted through bites and scratches. It caused severe illness and death in some of the monkeys. The sanctuary staff separated the groups and implemented testing and quarantine measures in response to the outbreak. Since the groups live in separate enclosures, scientists then had the chance to compare animals with similar backgrounds that had experienced very different social and disease environments. 

In total, three groups of monkeys experienced the outbreak while one had not. The team tested 

55 macaques to see how they responded to a choice between food that was put on a clean wooden surface and food placed on a surface covered with real macaque feces. The food with the feces was sealed under a layer of clear epoxy, so that the monkeys could see the food and poop without risking infection.

In the group that had been exposed to the outbreak, some of the individuals had been infected while others had lived alongside sick monkeys without getting sick. This allowed the researchers to question if experiencing an outbreak without getting infected could change the macaque’s behavior. To test that further, the clean surface was replaced with a brightly colored kitchen sponge in some of the scenarios to see if the animals were just avoiding unfamiliar objects. 

Previous studies found that macaques aren’t necessarily deterred by contamination—as long as the payoff is tempting. When presented with a favorite treat (such as a peanut) wild Japanese macaques would still eat food from a surface covered in feces, but will avoid it for food like grains of wheat.

Continued caution

The team found that macaques from groups that went through the outbreak were far less likely to eat the food from the contaminated surface. They ate from the fake contaminated surface in only 47 percent of trials. The monkeys that did not experience the outbreak ate from the potentially contaminated surface in 79 percent of trials.

The monkeys from outbreak-exposed groups also behaved similarly whether or not they themselves had been infected. According to the team, this suggests the behavioral change was associated with their experiencing living through the outbreak, instead of actually getting sick

“Groups have histories, and those histories show up in behavior,” added study co-author and UC San Diego cognitive psychologist Stephan Kaufhold. “Living through the disease outbreak appears to have made those monkey groups more cautious around food that looks contaminated.”

The virus was spread through blood or saliva from bites and scratches, and not through contaminated food. Interestingly, the macaques who saw their fellow primates get sick, were more reluctant to eat food placed on a surface that visually suggested contamination in some of the tests.

Disgust’s evolution

In addition to shedding light on how illness affects primate behavior, it also offers insight into the evolution of disgust. The team did not measure disgust directly, but found that monkey’s avoidance of potential sources of infection can change with their experience, similar to what humans do.

Human disgust is believed to play an important role in protecting us from pathogens. We recoil from the smell and sight of poop, spoiled food, and other potential sources of infection. Our sensitivity to those cues can also change depending on context.

Since primates are capable of social learning, the team believes that heightened pathogen avoidance could be learned from other members in the group and persist over time. Future studies could see if newly introduced animals adopt the behavior of a group that has already experienced an outbreak.

The post Monkeys also avoid germs after viral outbreaks  appeared first on Popular Science.

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Bat Beauty Contest returns October 24

With Alaska’s fat bears done packing on their winter weight and spooky season in full swing, it’s time to turn our collective animal-loving attention to a smaller mammal—bats. The Bureau of Land Management’s (BLM) annual Bat Beauty Contest returns on October 24 and promises “plenty of batty puns.”

Beginning Saturday, October 24, BLM will post photos of the competitors to their Facebook and Instagram accounts and ask you to vote for the best-looking one. All of the competing bats are part of wild populations that live on land managed by the public agency and are photographed by wildlife technicians. The winner will be announced (appropriately) on Saturday, October 31.

The bats in this competition are known for their squishy faces and clever names. In 2024, a hoary bat (Lasiurus cinereus) from Oregon named Hoary Potter took the crown. Other contestants included a long-eared myotis (Myotis evotis) named Honey Bunches of MyOtis, a myotis bat (Myotis myotis) named Robert Battinson, and western small-footed bats (Myotis ciliolabrum) named Batt Damon and Batlor Swift. The contest was not held in 2025 due to the 43-day-long federal government shutdown. 

a bat next to a logo that says bat week
A hoary bat at Isle Royale National Park in Michigan. Image: NPS Photo/Bat Conservation International.

The contest is not all bat puns and a way to keep the spirit of Fat Bear Week alive. It falls during Bat Week (October 24-31). Bat Week raises awareness about the Earth’s only flying mammal. More than just a Halloween symbol, bats play a critical ecological role as plant pollinators and through eating insects that can threaten crops and forests around the world. According to Bat Week, one bat can eat up to its body weight in insects every night. Only three species of bats eat animal blood, with two specializing in bird blood. Female lesser long-nosed bats even make tequila possible. Every spring, they migrate from south-central Mexico up to the southwestern United States, following “nectar corridors” of columnar cacti and agave plants. They pollinate agave plants, which are then used to make tequila and mezcal. When they feed on cactus fruits and nectar, they may also help disperse cacti seeds. Other bats eat pollen, nectar, or fruit.

Bats are increasingly threatened due to habitat loss, light pollution, and diseases like white-nose syndrome. This fungal disease infects the skin of the muzzle, ears, and wings of hibernating bats. In about 20 years, it has killed millions of bats across North America and affects about half of the species on the continent. Bats also are often misunderstood as carriers of diseases such as rabies. 

The planet is home to over 1,400 species of bats, and they make up almost 20 percent of all mammal species. Bats also can be found almost everywhere on Earth, even in desert and polar regions. To look up which bat species live near you, you can use Bat Week’s state bat database.

Stay tuned for more Bat Week updates!

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Astronomers discover first green star and the reddest star ever recorded

Despite the name, the universe’s white dwarfs can glow in a wide range of colors—even green. For the first time, astronomers have spotted a star that appears green to the human eye, and the reddest ever recorded. These outlier stars help explain how certain white dwarf stars would shine in green, pink, cyan, yellow, and purple if we actually saw them up close in space. These colorful findings are described in a study recently published in the journal RAS Techniques and Instruments.

Looking for the ‘perfect radiator’

White dwarf stars are the dense remnants left behind after stars like our sun reach the end of their lifespan. For most stars, their color gives a hint to their temperature. Cooler stars appear orange, warm stars like our sun look white. The hottest glow pale blue, similar to how a blacksmith’s iron will go from red to orange to white hot. Astronomers believed that white dwarfs followed this same rule. They even earned their name after the earliest examples were surprisingly hot and glowed in a white/pale blue. 

“Most stars, including most white dwarfs, behave like ‘perfect radiators,’ so their colour is set almost entirely by temperature. But nobody had really looked into what else might be possible for white dwarfs,” Mark Hollands, a study co-author and astronomer at the University of Warwick in England, said in a statement. “It turns out these incredibly dense stars can produce colours nobody expected, and some of them genuinely surprised me.” 

According to the team, the key to these colors is density. The atmospheres surrounding the coolest white dwarfs can reach about the same density as water (roughly 1 gram per cubic centimeter). They are also millions of times denser than the sun’s photosphere, the lowest layer of its atmosphere. Under these higher density conditions, any trace elements present (carbon, calcium, sodium, etc.) interact with the surrounding dense helium plasma. As they interact with the plasma, they can absorb light across a wider spectrum of colors than they would at lower densities. This then shifts the star’s color away from the more typical orange, white, and blue.

Unfortunately, no white dwarf sky is close enough for its color to be seen directly. Instead, the team calculated their color from data astronomers routinely collect—a star’s spectrum. The spectrum is a “fingerprint” that’s produced when starlight splits apart by wavelength, similar to how a prism splits sunlight into a rainbow. Astronomers ran these spectra through a computer model of what colors human vision can see to check what color a star’s light would appear to our eyes. 

Color-accurate simulated images of white dwarfs. Top Left panels: Sirius B is the nearest white dwarf to the Solar System, with a hot hydrogen atmosphere, resulting in a pale blue colour. WDJ1147-7449 is instead among the coolest nearby white dwarfs, giving it a featureless spectrum and an orange appearance. Top Right panels: Convective envelopes in these cool white dwarfs have dredged up carbon from their cores into their dense helium-dominated atmospheres, forming diatomic carbon molecules that lead to various pink hues. Bottom panels: Accretion of rocky debris from the white dwarf planetary systems enriches their cool helium atmospheres with elements such as calcium, magnesium, and sodium. The varying amounts/compositions of accreted material and white dwarf temperatures allow for a diverse array of colours, including green. In reality all stars would be many millions of times brighter than what can be shown on-screen. Image: Mark Hollands/University of Warwick
Color-accurate simulated images of white dwarfs. Top Left panels: Sirius B is the nearest white dwarf to the Solar System, with a hot hydrogen atmosphere, resulting in a pale blue colour. WDJ1147-7449 is instead among the coolest nearby white dwarfs, giving it a featureless spectrum and an orange appearance. Top Right panels: Convective envelopes in these cool white dwarfs have dredged up carbon from their cores into their dense helium-dominated atmospheres, forming diatomic carbon molecules that lead to various pink hues. Bottom panels: Accretion of rocky debris from the white dwarf planetary systems enriches their cool helium atmospheres with elements such as calcium, magnesium, and sodium. The varying amounts/compositions of accreted material and white dwarf temperatures allow for a diverse array of colours, including green. In reality all stars would be many millions of times brighter than what can be shown on-screen. Image: Mark Hollands/University of Warwick

The first green and the reddest red

The team applied this method to several white dwarfs across the cosmos. They found that their colors fall into distinct groups linked to what makes up a star’s atmosphere. Carbon-rich white dwarfs generally appear pink or purple. Stars enriched with debris from busted asteroids and comets, the remains of old planetary systems, tend to be more yellow. Cooler white dwarfs with atmospheres of mixed hydrogen and helium show a more cyan or pale blue tinge. This cyan-pale blue is caused by hydrogen molecules colliding with helium atoms inside their ultra-dense atmospheres.  

The most striking example is WD J1330+6435. This star is about 7,232 degrees Fahrenheit (4,000 degrees Celsius) and around 284 light-years away from Earth. Over time, it has gathered rocky material from its planetary system. All of this extra material enriched its atmosphere with calcium, lithium, and sodium. The result—a chartreuse green appearance in the team’s models. As far as the researchers are aware, no other star (living or dead) has ever been credibly reported as green.

Enriched from above: The cool white dwarf WDJ1330+6435 has accreted sodium-rich rocky material from its planetary system into its atmosphere. The immense atmospheric density causes the sodium to absorb light over broad range of yellow, orange, and red wavelengths, giving the WDJ1330+6435 a ghostly green appearance. Image: Mark A Garlick/University of Warwick.
Enriched from above: The cool white dwarf WDJ1330+6435 has accreted sodium-rich rocky material from its planetary system into its atmosphere. The immense atmospheric density causes the sodium to absorb light over broad range of yellow, orange, and red wavelengths, giving the WDJ1330+6435 a ghostly green appearance. Image: Mark A Garlick/University of Warwick.

“The traces of sodium in the atmosphere of this white dwarf absorb the orange part of the spectrum, leaving behind a ghostly green glow,” added Hollands. “Imagine standing on a planet and looking up at a green star. It feels like something out of science fiction.” 

On the opposite end of the spectrum, the team identified what could be the reddest star ever recorded—WD J1011+2845. This white dwarf is only 48 light-years away from Earth, and has a deep convection zone. This zone is full of carbon that’s been lifted up from the star’s core to its surface. The carbon molecules then distort the star’s light so much that almost all of it is squeezed into wavelengths beyond 600 nanometres. This wavelength produces an unusual deep salmon-pink glow.

Enriched from below: The cool white dwarf WDJ0902+2010 has a deep convection zone within its helium dominated outer envelope. The convection zone has reached the white dwarf core, lifting interior carbon to the surface, and forming carbon molecules. These C2 molecules strongly absorb light across the optical range, including blue, green, and yellow wavelengths, resulting in WDJ0902+2010 appearing pink to the human eye. Image: Mark A. Garlick/University of Warwick.
Enriched from below: The cool white dwarf WDJ0902+2010 has a deep convection zone within its helium dominated outer envelope. The convection zone has reached the white dwarf core, lifting interior carbon to the surface, and forming carbon molecules. These C2 molecules strongly absorb light across the optical range, including blue, green, and yellow wavelengths, resulting in WDJ0902+2010 appearing pink to the human eye. Image: Mark A. Garlick/University of Warwick.

What are the odds?

The team also studied 151 white dwarfs located within about 65 light-years (20 parsecs) from Earth. Only five of these showed unusual colors, two yellow and three pink. This suggests that about 1 in 30 of the universe’s white dwarfs shine with an unusually colored light. 

The team then measured the color temperature of the remaining 146 white dwarfs. Color temperature is commonly used to describe light bulbs using degrees Kelvin—warm white at 3,000K, cool white at 6,000 K, etc. The median color temperature of the sample was approximately 6,800K, which our eyes perceive as white. This measurement corrects a common misconception that white dwarfs are typically blue. The hotter and bluer white dwarfs are mostly brighter, so they can be seen from further away and are over-represented in surveys that only look at a star’s brightness.

“One in thirty might not sound like a huge fraction, but across the entire population of white dwarfs in the Universe, that is still a lot of oddly coloured stars out there,” added study co-author and University of Warwick astronomer Boris Gänsicke. “Yet if we take the median across a representative population of white dwarfs, we found that the average white dwarf really is white.”

The post Astronomers discover first green star and the reddest star ever recorded appeared first on Popular Science.

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Jackie the bald eagle’s final cause of death revealed

The Ojai Raptor Center released the final necropsy results for Jackie, an internet-famous bald eagle mother who was in their care this summer. Jackie was brought into the bird rehabilitation center weak and dehydrated following an altercation with another eagle in July. 

Officially designated as Patient 26-519, Jackie’s necropsy revealed a “complex and unusual disease process involving severe, chronic inflammation and ulceration of the stomach, persistent internal bleeding, anemia and secondary bacterial sepsis.” She was also diagnosed with Highly Pathogenic Avian Influenza (HPAI) commonly called bird flu, which was behind severe stomach ulceration. Raptors (eagles, hawks, falcons, owls, etc.) are highly susceptible to the virus 

All of these medical complications developed over time and ultimately contributed to her death on August 10.

“These findings have helped connect many of the pieces we were seeing throughout her hospitalization and provided a better understanding of the challenges she faced,” the Ojai Raptor Center wrote. “We are grateful to the many veterinary specialists, laboratories, wildlife agencies and partner organizations who worked alongside our team to understand her illness and provide her with the best possible care. Caring for her was an extraordinary privilege for our entire team.”

The full report can be read in Jackie’s veterinary medical journal. The necropsy was preformed by veterinary pathologists at the San Diego Zoo Wildlife Alliance.

Friends of Big Bear Valley (FOBBV), the non-profit organization that runs the live cameras where viewers from all over the world watched Jackie and her partner Shadow, said that they will follow up with their thoughts once their team has had time to process the report.

“The story of the Big Bear bald eagle reflects the powerful connection people feel to these iconic birds,” California Department of Fish and Wildlife Director Meghan Hertel added. “We’re grateful to everyone who cared for her and worked to support her well-being.  Understanding the results of these tests is an important part of learning from this case and can help inform the care and treatment of other eagles and wildlife in the future.”

a bald eagle standing on a perch inside
Jackie on a perch at the Ojai Raptor Center in July. Image: Ojai Raptor Center.

Jackie’s story

Jackie was born, raised, and lived in Big Bear Valley in Southern California. Prior to the 2011-2012 nesting season, no bald eagle chicks were known to have ever hatched in Big Bear Valley. Then came Jackie, named after a forest ranger and born to parents Ricky and Lucy in 2012. 

During the 2016-2017 nesting season, Jackie took over a nest where Friends of Big Bear Valley (FOBBV) had a camera stationed. In 2018, she had two chicks named Stormy and Big Bear Baby (or BBB) with her first mate, Mr. B. 

Her long-time partner Shadow entered the picture in summer 2018. He showed up at the nest and would not leave. FOBBV called the new male Shadow because he appeared so determined to stay in the nest, and the team initially believed he was one of Jackie’s siblings, also named Shadow. The eagle’s plumage indicated he was one year older than the other Shadow and not Jackie’s sibling, but the name stuck. 

Shadow continued to hold his ground and Mr. B gave up and eventually left. Jackie then accepted Shadow as her new mate.

Wildlife cameras documented Jackie and Shadow’s life together, offering viewers a direct look into the brutality and beauty of nature. The pair successfully raised chicks in 2019 (Cookie and Simba) and 2022 (Spirit). The pair’s eggs failed to hatch in 2023 and 2024. In 2025, Jackie laid three eggs that all hatched in early March. However, a strong snowstorm dumped up to two feet of snow and battered the nest with strong wind and only two of the chicks (Sunny and Gizmo) survived.  

In January, Jackie laid two eggs in the nest, but ravens destroyed them. She later laid two more eggs that hatched in April and named Luna and Sandy. The name Sandy is in honor of FOBBV’s former executive director Sandy Steers who died from cancer in February. 

an adult baled eagle with two eaglets
Jackie, Luna, and Sandy on their nest in May 2026. Image: Friends of Big Bear Valley.

Jackie’s injury and death

On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she had an altercation with two other subadult eagles. She successfully fended off the other eagles by turning over and using her talons, but could not fly far away. 

She was transferred to the Ojai Raptor Center, where she was diagnosed with severe anemia. Her anemia worsened during the first week of August, the Ojai Raptor Center said that she was in unstable condition on August 9. Her packed cell volume (PCV) fell below percent, before rising to nine percent.  

On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she had an altercation with two other subadult eagles. She successfully fended off the other eagles by turning over and using her talons, but could not fly far away. 

She was transferred to the Ojai Raptor Center for care, where she was diagnosed with severe anemia. Her anemia worsened during the first week of August, the Ojai Raptor Center said that she was in unstable condition on August 9. Her packed cell volume (PCV) fell below percent, before rising to nine percent. 

Jackie died early in the morning on August 10. The necropsy did not reveal a single cause of death, and instead pointed to several factors including severe anemia, blood clots in her wing and one kidney, and liver and lung abnormalities.

Jackie’s resilience inspired millions of people around the world. To honor her memory, FOBBV accepts donations to support its conservation efforts in the area.  Supporters can also donate to Ojai Raptor Center’s Bald Eagle Recovery Campaign. 

The post Jackie the bald eagle’s final cause of death revealed appeared first on Popular Science.

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When ‘T. rex’ died, a new giant fungus named ‘D-rex’ took over

It’s a fungi-filled world and we are just living in it. There are roughly 150,000 to 157,000 known species of fungi, and now there is a new giant species to add to that tally. 

A team of scientists exploring the forests of Yunnan in southern China discovered the new fungus, which shows just how large these organisms can grow. The new species Dianjunus rex grows vertical fruiting bodies (the top part of the fungi that we usually see as a mushroom) that can grow as high as a foot (50 centimeters) and weigh close to five pounds (2.2 kilograms). 

This new fungus is the largest known species within the phylum Ascomycota, the largest known phylum of fungi with over 64,000 known species. The new fungus is described in a study recently published in the journal Frontiers in Fungal Biology.

“This remarkable species represents a new fungal family, Dianjunaceae, and provides a rare window into the evolution of extreme fungal body forms,” Indunil C. Senanayake, a study co-author and mycologist at the Germplasm Bank of Wild Species of the Kunming Institute of Botany in China, said in a statement. “The discovery illustrates how much fungus biodiversity remains to be discovered in East Asian forests.”

The scientists spotted the fungus during fieldwork in the temperate coniferous forests near Damaidi and Yipinglang and in a tropical rainforest near Nanbang in southern China. They noticed large whitish fruiting bodies (called stromata) coming out of some fallen wood that belonged to an unknown species of Ascomycete fungus. 

Stromata of Dianjunus rex in the field. (a, c, d, f) Stromata attached to host roots. (b, e, g, h) Stromata around host plant. (a) Collectors. (i) Total weight of largest bilobedstromata. Image: Song, Yan, Pérez-Moreno, Zhang, Yang, Xie, Su, Liu, Wang, Liu, Yang, Yang, Liu, Shi, Wan, Cheewangkoon, Dai, Senanayake and Yu
Stromata of Dianjunus rex in the field. (a, c, d, f) Stromata attached to host roots. (b, e, g, h) Stromata around host plant. (a) Collectors. (i) Total weight of largest bilobedstromata. Image: Song, Yan, Pérez-Moreno, Zhang, Yang, Xie, Su, Liu, Wang, Liu, Yang, Yang, Liu, Shi, Wan, Cheewangkoon, Dai, Senanayake and Yu

Ascomycetes don’t always sprout traditional mushrooms, but release their spores from tiny, sac-like structures inside or on the surface of such fruiting bodies instead. They typically grow on woody roots of Chinese cork oak trees.

The team collected the curious fruiting bodies, and grew spores back in the lab to study the fungus’ morphology and its genome. The genetic tests and a detailed study of its morphology revealed that the fungus is a new species, a new genus, and even a new family. 

They named it Dianjunus rex (which the team calls D-rex for short), for its regal size and the ancient Dian kingdom. This ancient civilization in Yunnan reached its height during the second and first centuries BCE.

The team also found a connection to dinosaurs beyond its nickname which sounds like T. rex. It appears that this fungi family arose around 65 million years ago, or only one million years after the Cretaceous-Paleogene mass extinction event. This most famous of Earth’s mass extinctions wiped out the dinosaurs and countless other animals and plants.

“This timing raises an intriguing possibility. After the mass extinction, forests experienced dramatic changes, including the sudden availability of large amounts of dead plant material,” added Senanayake. 

For fungi, this kind of environmental disruption may have created new ecological opportunities for it to fill.

As for its size, D-rex’ fruiting bodies grow about 20 to 30 centimeters taller than other Ascomycetes. The team thinks this size might help the wind disperse their spores better in dense forests. However, a large fruiting body like D-rex requires a lot of energy, so the strategy may have evolved if the ecological benefits outweighed the energy costs.

The team also believes that there are more fungi waiting to be discovered in subtropical China—we just need to keep looking. 

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Sled dogs have stubby legs for a reason

They’re some of Earth’s most powerful athletes, traversing thousands of miles of rough terrain in sub-zero temperatures, through blinding snow, and biting winds. Sled dogs have been helping humans travel across the planet’s coldest regions for centuries, hauling supplies, people, and equipment across the snow and ice. In the process, this important role that goes above and beyond simply being “man’s best friend” could have a visible impact on their evolution.

Sled dogs may have evolved shorter legs to help them pull loads more efficiently. Currently working sled dogs and those that lived about 2,000 years ago have six percent shorter leg bones than similar species, according to a study published today in the journal iScience. These findings could help biologists trace the origins of sled dogs and understand more about how dog-powered transportation spread over the past 9,000 years. 

“Sled dogs have played an indispensable role in communities in the Arctic,” Mitya Kletzerman, a study co-author and an archeologist at the University of Haifa in Israel, said in a statement. “Without dogs, people couldn’t move as efficiently to hunt, relocate as conditions changed, or travel between communities to exchange knowledge and share new ideas. Understanding how the practice evolved could give us new insights into how people adapted to life in the Arctic.” 

As of now, our earliest archeological evidence associated with dog sledding comes from 9,000-year-old sled parts and dog remains uncovered in 2017 on Zhokhov Island (present-day Russia). Sledding equipment like this is rarely found in the archaeological record, so it has remained difficult to pinpoint when and where the practice first emerged or spread. 

Earlier studies have shown that work associated with humans can leave traces in an animal’s skeleton. Reindeer used for racing, carrying loads, and pulling have limb bone differences compared to those that do not pull. Kletzerman and her team were curious if sled dogs have also developed particular skeletal traits that have helped them adapt to all of the physical demands of pulling a sled. 

In the study, the team developed a biomechanical model to help them understand how a dog’s body handles the work of pulling a sled. The model showed that one effective way to pull a sled loaded with material is for a dog to lower its center of gravity. This increases the canine’s ability to generate pulling force.  

“When people or animals pull a load, it tends to tip them backward. A lower or more forward position of the center of mass counteracts this effect, allowing greater pulling force,” Kletzerman explained. 

They then tested whether modern sled dogs have skeletal proportions that can lower their center of mass. They analyzed bones in 60 different modern canids, including sled dogs, wolves, spitzes, and mongrels. They then compared the lengths of five leg bones. Three in the forelegs (the humerus, radius, and ulna) and two in the hind legs (femur and tibia).

After accounting for overall skeletal size, they found that sled dogs have relatively shorter radius, ulna, and tibia bones than their non-sled pulling counterparts. These bones measured about six percent shorter on average.  

“It’s unclear how this trait developed, but selective pressure may have preserved it, because it gave sled dogs an advantage over other dogs,” Kletzerman said. 

To see if this characteristic already existed in ancient dogs, the team analyzed 82 ancient dog bones and three skeletons. The three skeletons were from ritually buried dogs uncovered from three archaeological sites associated with ancestral Inuit populations in present-day Chukotka, Russia, and date to 2,000 to 500 years ago.  

Nearly 89 percent of the bones were consistent with the modern sled-dog pattern of shorter leg bones, as were all three ritually buried dogs. According to the team, this suggests that the skeletal pattern may be an effective way to identify that canine remains belonged to a sled dog, even when archaeological remains are incomplete or do not have any direct evidence of sled equipment. 

“Dogs have been working alongside humans for thousands of years, but we’re only beginning to understand how that partnership shaped them,” Kletzerman concluded.

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How to watch Churchill’s famous polar bears live

The internet’s favorite Fat Bears in Alaska are not appearing on wildlife cameras quite as much these days. The salmon has been eaten, the Fat Bear Week crown has been won, and it’s time to survive the winter ahead. However,  some other bears from the great white north are getting their close-up.

Explore.org and Polar Bears International run eight different livestreams from Churchill, Manitoba, Canada. Known as the polar bear capital of the world, Churchill’s Wapusk National Park is home to one of the world’s largest concentrations of polar bear (Ursus maritimus) maternity dens. During October and November, viewers can watch bear families wait for sea ice to form. 

Twenty populations of polar bears live in the Arctic. The population living along the Western Hudson Bay is one of the most comprehensively studied and best known. It is part of Canada’s “Seasonal Ice Ecoregion.” In this area of the Arctic, the sea ice completely melts in the summer, typically in July. While the bears may remain sporadically active on land, in the summer, they generally create day beds or curl up in the bush to rest. The pregnant females will often settle in or near their dens for several months to rest where it is cooler and with less mosquitoes. Many of these dens were first excavated by bears generations ago.

In the fall, all of the bears except the pregnant female will increase their activity and move closer to the coast. Here, the bears will hunt for seals once the bay freezes over again. From early October onward, they will gather on the tundra along the shores of Hudson Bay, waiting for ice to form. As soon as the first coastal ice is thick enough to support their weight, they will head out to find seals. They may continue to trek back and forth between ice and land at first, but they primarily head out onto the bay until it begins to thin and they ashore again in the summer.

These cameras are one way for scientists and the public to aid in real scientific research. In December 2025, scientists here confirmed that a wild female polar bear adopted a cub that was not her own. This rare behavior was captured on cameras during the polar bear’s annual migration along Western Hudson Bay. 

The mother bear (designated as bear X33991) was first spotted in spring 2025, when she came out of her maternity den with one tagged cub. When scientists saw her again in the fall, she had two cubs. One cub had a tag and one did not, indicating that the untagged cub was not hers. The survival rate for a polar bear cub into adulthood is about 50 percent, so only time will tell how this blended family will do. 

Viewers can also take a virtual ride on the Tundra Buggy Lodge from two different angles. The lodge is made of tundra buggies that are linked together like a train. This moving hotel includes staff quarters, a dining area, a supply cart, and two carts for guests.

By night, viewers can also take in another of the north’s natural wonders with the aurora borealis cam. The northern lights livecam is on top of the Churchill Northern Studies Center and located directly underneath the aurora oval. This spot is considered one of the best places to watch the aurora dance across the night sky. The aurora season is only just beginning, with late winter and early spring being the best times to tune into this camera.

And if birds are more your thing, a raven cam is streaming from Cape Churchill Wapusk National Park. The resident ravens selected the topside of a radar reflector attached to the Cape Churchill observation tower for their nest. This “cabin in the sky” has also been home to numerous biologists researching the local wildlife since the 1970s. This camera will be switched off at night to preserve power.

The organizations also provide highlight reels to help viewers catch up on what to watch for this winter. Happy polar bear season!

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Monarch butterfly saved after landing in refried beans

A migrating monarch butterfly (Danaus plexippus) recently brought into Sweetbriar Nature Center in Smithtown on New York’s Long Island came with a unique backstory. The male butterfly flew into a nearby house and landed on a pot of refried beans. The man living there took the butterfly out of the pan, but by morning the butterfly still could not fly. There was only one thing left to do for the injured insect—bring him to the professionals.

“Butterflies are incredibly delicate, and even handling them can cause additional damage or leave them unable to fly,” Janine Bendicksen, Sweetbriar Nature Center’s Director of Wildlife Rehabilitation, tells Popular Science. “That makes butterfly rehabilitation especially challenging—we have to be extremely careful with every step.”

The team got to work on fixing this unusual patient. They started by checking the butterfly for a parasite called OE (Ophryocystis elektroscirrha) that can live on monarchs. If the insect is parasite-free, the team can then assess the injuries and determine whether rehabilitation is possible. Butterflies are very delicate, and just handling them can cause additional damage.

“In cases where a monarch has lost part of a wing, we may be able to transplant a portion of a donor wing,” says Bendicksen. “When the circumstances are right, we can carefully attach the donor wing to the injured butterfly.”

The team gently sprayed the butterfly’s wings with water several times to remove the bean residue that prevented him from flying. Then, a challenge arose. How do you remove the greasy residue from such delicate wings? The solution came from a common powdery substance found in kitchen pantries—cornstarch.

“We use starch regularly in wildlife rehabilitation to help dry out materials, and we had also previously used starch when replacing a wing on another monarch,” Bendicksen explains. “Because we already knew it was safe and effective in that context, we felt it was a good option for this particular situation. We were looking for something that would help remove the remaining moisture and residue without causing additional damage to the delicate wings.”

The cornstarch trick worked. The monarch was able to fly again. The team gently transported him outside and he took to the skies. Monarchs are currently on their way to the overwintering grounds in the forested mountains of Central Mexico. Their migrations are multigenerational, with roughly four generations of monarch butterflies emerging throughout the year. This butterfly may have been in the third generation (lays eggs in the north, but does not migrate) of the fourth generation that treks south. 

“It’s not often that we are called upon to rehabilitate a butterfly,” Bendicksen says. “Most butterflies have relatively short lifespans, but when we receive a monarch in the fall—especially one that will travel thousands of miles on its migration to Mexico—we do everything we can to give it the best possible chance.”

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Rocky the pumpkin wins ‘Superbowl of Pumpkin Weigh Offs’ at 2,389 pounds

For the fifth time, pumpkin legend Travis Gienger won the Safeway World Championship Pumpkin Weigh Off today in Half Moon Bay, California. The gigantic gourd named Rocky weighed 2,389 pounds. It could be baked into approximately 1,194 pumpkin pies, and weighs about the same as an American bison (Bison bison) or a 2015 Chevy Spark.

The biggest gourd from this event tipped the scales 2,749 pounds and was grown by Gienger in 2023. On October 10, a new world record was set at the Southern New England Giant Pumpkin Growers Weigh-Off. Ron Wallace of Greene, Rhode Island’s pumpkin weighed 3,156 pounds, beating the previous record-holder by about 300 pounds.

As champion, Geigner will earn $9 per pound in prize money, so $21,900 total. He also will receive a Pumpkin King Champion Ring, the Mel Mello Sr. Grand Champion Growers Jacket, and other honors.

The 53rd annual event also featured a special appearance and carving by legendary pumpkin carver and farmer Mike Valladao. Affectionately called the “Picasso of Pumpkin Carvers,” the gourd artist commemorated his 40 years at the Half Moon Bay Art & Pumpkin Festival.

a carved pumpkin
The pumpkin that Mike Vallado carved during the festivities. Image: Safeway World Championship Pumpkin Weigh Off via Facebook.

The event began in 1974 as a friendly challenge between Half Moon Bay, California, and Circleville, Ohio, to see who could grow the biggest pumpkin. Half Moon Bay won that first showdown with a pumpkin weighing only 132 pounds. Today’s mega gourds can weigh more than 20 times as much. The event has also become an annual pilgrimage for the pumpkin growers who spend months nurturing their enormous Atlantic giants (Cucurbita maxima). These jumbo gourds sometimes gain dozens of pounds in a single day during peak growing season (August through September).

The event is an officially sanctioned Great Pumpkin Commonwealth competition, with weighing and inspection officiated by the GPC and San Mateo County Department of Agriculture Office of Weights and Measures.

Related Pumpkin Stories

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Bee stingers work like saws to pump venom  

It’s one of nature’s seemingly magical tricks. A honey bee (Apis mellifera) stings a victim, and the stinger will still pump venom into a wound even after it has fully detached from the bee’s body. Thanks to some high-speed video, we may finally know the secrets behind this sting. 

A team in Australia found that the tiny 2 millimeter (or only 0.08 inch) stinger of a honey bee works like a double-piston micro-pump. It pumps in two different directions and can deliver a continuous flow of venom. The findings are described in a study published today in the journal PNAS.

“We’ve known since as early as 1910 that the venom sac of a honey bee stinger empties into a chamber with little pumping elements called valves, but until now we didn’t know exactly how they work,” Fiorella Ramirez-Esquivel, a study co-author and entomologist at Macquarie University, said in a statement. “If you’ve ever been stung by a bee, you’ll know it’s a very painful process, but now we’ve been able to identify all the working parts packed into the tiny stinger.”

In bees, autotomy is when a worker bee thrusts its stinger into a target and then leaves the stinger behind. The stinger then continues to penetrate into the target tissue and inject venom all on its own. 

To better understand how autotomy works, the team from Macquarie and the University of New South Wales had bees sting a clear gel that mimics human skin, while taking high-speed video. They saw that the tiny stinger itself contains several different components including one venom sac and a pumping chamber, muscles, and nerves. The stinger also has two sharp, pointed lancets. These lancets slide backwards and forwards on a system of rails (called the olistheter), similar to a reciprocating saw. These saw-like lancets are what pushes the stinger deeper into the skin and also pumps the venom.

Each of the two long lancets has a valve attached to it that sits inside of the pumping chamber. The team found that these valves change shape to form a seal during the downstroke. They then collapse during the upstroke, creating pressure for pumping while minimizing backflow when refilling.

“Finally, and perhaps most dramatically, as the valves meet in the middle of the stroke, they change shape again to push past each other,” said Ramirez-Esquivel. “This is a remarkable strategy to pump fluid since maintaining a seal is vital to effectively transmit pressure. The unique geometry of the valves is the key; they act as collapsible pistons and—by pumping in opposite directions—they’re able to deliver a continuous flow of venom.”

The team continued to explore the mechanics and flow of the stinger with microCT scans. They then used these scans to 3D print a small robot of the bulb chamber and lancets. The tiny bee-bot confirmed these key features of the pumping cycle.

“The double piston design adds complexity but it’s the key to the stinger being able to deliver venom continuously in a compact, autonomous unit,” said Dr Ramirez-Esquivel.

Understanding this mechanism could inspire designs for new micropumps to deliver medicine to human patients in a less invasive way.

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Giant tortoises now outnumber people in the Seychelles

As Joanthan the Aldabra giant tortoise (Aldabrachelys gigantea) approaches his 195th birthday this December, there is some good news for his fellow tortoises. The previously endangered species is thriving and stable in the Seychelles, according to a study published this week in the journal Ecology and Evolution.

Aldabra giant tortoises are one of the world’s largest land tortoises. They weigh up to 550 pounds and live 150 years. These gentle giants are native to Aldabra Island, one of the Seychelles northeast of Madagascar in the Indian Ocean. They are also found in the Galápagos, but the population on Aldabra here is much smaller. As the largest animal on  Aldabra, they play an ecological role that is similar to elephants. Tortoises are the main consumers of vegetation and will change the habitat while searching for food. They will knock over small trees and shrubs all to get those nutritious leaves. Any seeds not digested will pass through the tortoise’s digestive tract and become food for many other animals.

To check on the population at Aldabra, a team from the University of Exeter in England and the Seychelles Islands Foundation Aldabra analyzed giant tortoise counts collected between 2018 and 2022 on Aldabra Atoll. They found that the population currently stands at approximately 180,000 individuals.

The survey is the first rigorous, atoll-wide estimate of the population and the first update since the late 1990s. At the time, it was believed that about 100,000 tortoises were living on the island. 


“More than 180,000 giant tortoises roaming freely on our atoll is proof of what long-term commitment to conservation can achieve,” Frauke Fleischer-Dogley, a study co-author and the CEO of the Seychelles Island Foundation, said in a statement. “This is wonderful news for Seychelles, for the world, and for everyone who has worked to protect Aldabra.”

The team found that the population was relatively stable during the survey period, with a best estimate of almost 183,000 adult and sub-adult tortoises. This number is a far cry from the 19th century. Heavy exploitation and overhunting reduced Aldabra’s tortoises to fewer than 1,000 individuals. Aldabra became a strict nature reserve in 1981 and a UNESCO site in 1982, and these and other conservation measures have helped them rebound.  

a group of giant tortoises on grass
Giant tortoises grazing in large numbers on Aldabra Atoll. Image: Dennis Hanse.

“Aldabra’s giant tortoise monitoring programme is one of the longest running in the region, but the atoll’s dense vegetation makes counting tortoises genuinely difficult in places,” added study co-author and University of Exeter biologist Nancy Bunbury. “By modelling what we didn’t see, as well as what we did, we’ve produced the most reliable baseline yet for this iconic Seychelles species, establishing a benchmark we can use to track the population for decades to come.”

However, the team cautions that this new figure does not mean that the population has nearly doubled since 1999. The earlier surveys did not account for tortoises present on the atoll, but not seen by surveyors, and were possibly hidden in dense scrub or shade. This new survey took advantage of a more sophisticated statistical technique called Bayesian hierarchical distance sampling. It corrects for both missed animals and for differences in visibility across habitats. 

Since these earlier methods likely missed tortoises, the team suggests that previous figures were probably underestimated. At the same time, the population has genuinely grown and now appears healthy and stable.

The study also found that tortoises are at the highest densities in Aldabra’s grasslands, aka  “tortoise turf.” They also are often found on open exposed surfaces and in open mixed scrub. The reptiles were harder to detect in dense scrub, mangrove, and habitats covered in a shrubby plant called Pemphis. The new modelling helped correct for reduced visibility from the scrub, Pemphis, and mangrove. 

Even with this welcome good news, the team says that vigilance remains essential. Aldabra’s climate is changing, and seeing longer and more frequent droughts. Scientists suspect that these serious dry spells will reduce the shade and food available to tortoises, and rising sea levels threaten low-lying parts of the atoll.

The tortoises are also threatened by invasive mammals. Though feral goats were eradicated in 2012, cats and black rats will still eat tortoise eggs and hatchlings. While there are plans to eradicate the rest of these invasive species, reduced eggs could hinder further population growth. 

“These results are great news for the tortoises and testament to the fantastic work done in the field,” added study co-author and University of Exeter, Cornwall statistical ecologist Dave Hudson. “But it’s important to remember that the numbers provide a baseline – not an endpoint. Hopefully we have provided the conservation managers the evidence they need to track future change and act early as the tortoises face increasing pressures from climate change, drought and invasive species.”

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Rare red bat rescued in Maine gobbles up mealworms

A rare Eastern red bat (Lasiurus borealis) is recovering after being found struggling in the surf on a Maine beach. Earlier this week, the Center for Wildlife in Cape Neddick, Maine, shared new footage of the winged mammal chowing down on a hearty plate of mealworms—a good sign for her recovery.

“She was very lethargic upon admission, and is now feisty and active,” Kristen Lamb, the Center for Wildlife’s Executive Director tells Popular Science. “She has been eating well, and responding to treatment including fluid therapy, temperature regulation and a specific bat habitat that allows her to mimic natural behaviors and reduces stress.”

Mealworms are the larval form of the yellow mealworm beetle and a common bat food. To keep these mealworm meals close to what a bat would be eating in the wild, the team even supplements what the worms themselves eat. This way, the nutrients inside of bugs resembles the contents of wild insects versus store-bought mealworms.  

Eastern red bats like this one are one of eight bat species found in and around southern Maine. They are considered tree bats because they act more solitary and roost in trees among the foliage instead of in large communal groups or in caves like most bat species. 

“They are camouflaged as they hang curled up in the furry membranes of their tails, suspended by usually one foot upside down, giving the appearance of a curled leaf or pine cone moving in the breeze,” says Lamb.

Red bats are also a species that eats “on the wing.” This means that they must be handfed or learn how to eat and drink from a dish if under human care. In the wild, they can grab insects from the air while flying, and glide and dip down to drink water while still flying.

Bats also have high metabolisms, and specific nutritional, temperature and humidity requirements. This isn’t because they are picky. These factors all help them roost. 

“[Bats] hang upside down by their back feet, which their circulatory systems are adapted for versus ours which would result in a pounding headache!,” Lamb explains. “Clinic staff must have knowledge of this, along with their anatomy, physiology, sensitivity to medication and handling techniques in order to successfully treat them.”

Though humans generally think of bats more during spooky season, bats like these are a critical part of the ecosystem all year and directly tied to our health. They gobble up mosquitoes that can carry West Nile Virus or EEE, providing a natural and free form of pest control. 

The team is hopeful that this little red bat can make a quick recovery and be released back into the wild, but also want to be sure she’s okay.

“Red bats are migrating right now and we don’t want her to miss her window,” Lamb says. “At the same time, she is recovering from the shock of being submerged in the cold Atlantic and if we release her before she can do everything healthy red bats can do in the wild, she would succumb to predators, the elements, or starvation shortly after release.”

The Center for Wildlife treats up to 2,500 injured and orphaned wild animals from a 100-mile radius per year. The center operates without federal funding and donations can be made through their website. 

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Pink, pretty, and protective. A dumbo octopus is here with a message from the deep-sea.

She’s bubblegum pink with a permanent little smile. She sports a pretty flower on her head sports a black tattoo on one of her eight arms. But don’t let this dumbo octopus’ adorable exterior fool you. Miss Abyss is here on serious business. 

“Miss Abyss is a dumbo octopus from the deep-sea, and she is on a journey all across the country looking for allies to support her to help defend the deep-sea,” Angelo Villagomez, a research fellow at the Center for American Progress (CAP), tells Popular Science. 

While Miss Abyss herself is an octopus illustrated by CAP research associate Jasia Smith, dumbo octopuses (genus Grimpoteuthis) are very real cephalopods. They live on the ocean floor, and many species can be found at extreme depths of 9,800 to 13,000 feet and are only about 8 inches tall. 

CAP’s’ Miss Abyss campaign is using the dumbo octopus to raise awareness about protecting public waters from deep-sea mining using the Flat Stanley method. Based on the children’s book Flat Stanley, children are are asked to take pictures of a paper doll in places near where they live for a popular school project. For Miss Abyss, supporters are asked to print out a picture of her and then take a photo or video of her in a place that represents their state or home and share it on social media. Supporters are also encouraged to sign CAP’s petition.

“One of the most popular things in the United States is our public lands and our public waters,” Villagomez says. “We’re creating a fun and engaging way for people of all ages to be creative and basically showcase their support.”

a poster of a small pink octopus with the text "i will succeed because i am miss abyss"
While Miss Abyss attempts to travel to all 50 states, real dumbo octopuses can be found in some of the deepest parts of the ocean. Image: Center for American Progress/Miss Abyss via Instagram.

What is deep-sea mining?

Deep-sea mining is the extraction of mineral resources including manganese, nickel, cobalt, copper, and rare earth elements from the ocean floor. Proponents of future deep-sea mining say that these and other minerals could help speed up the development of clean energy technologies. The global demand for nickel, cobalt and rare earth elements needed for digitization and decarbonization may double by 2040 to meet carbon emissions goals. Some also see the deep-sea as a safer alternative to mining on land. 

But the process could cause destruction to a critical ecosystem that we still do not know much about. As of April, only 28.7 percent of the global seafloor has been mapped. A 2025 report commissioned by the National Ocean Protection Coalition found that in the next 15 years, the economic, environmental, and technical challenges associated with deep-sea mining would make its profitability or commercial success highly unlikely. Waste discharge from deep-sea mining could also reduce food availability for the species that live there.

On November 12, 2025, the Bureau of Ocean Energy Management (BOEM) announced a Request for Information and Interest (RFI) for leasing land off the Northern Mariana islands for mining. While the comment period ended on January 12, organizations from Guam and the Northern Mariana Islands and their national partners collected over 60,000 petitions, letters, and comments opposing the plans to allow deep sea mining near the Mariana Trench.

On August 17, BOEM announced a Proposed Leasing Notice (PLN) and a 60-day comment period that outlines the terms and conditions of the potential sale. The date for the lease sale is currently set for December 16, 2026.

“Some of the least disturbed coral reef ecosystems on the planet are on these isolated Pacific islands in the U.S. Pacific territories,” says Villagomez. “I think part of the human spirit is knowing that there are places that are unexplored, that there are things on our Earth that are still yet to be discovered.”

As a result, roughly 31 million acres near American Samoa and 69 million acres near the Mariana Islands’ outer continental shelves could go up for auction. The U.S. federal government has also proposed lease sales to advance deep-sea mining near Alaska and Virginia. 

“We’re not talking about a small [mine on land] where it’s one open pit,” says Villagomez. “It’s as far as the eye can see in every direction.”

Environmental and indigenous rights

In addition to the environmental risks, deep-sea mining also presents an Indigenous sovereignty issue. The ocean is a sacred part of the identity, spirituality and traditions of the Chamorro and Refaluwasch people of the Marianas, and other communities of American Samoa.

“I am Indigenous Chamorro, born in Guam, but my family is from Saipan. I grew up knowing that I lived next to the Mariana Trench,” Villagomez says. “I remember being out fishing with my dad, and he would then tell dad jokes, like ‘Oh you see the mountain there? It’s the tallest mountain in the world because it stretches all the way down to the Mariana Trench.’” 

That was not just a dad joke. At 6.8 miles below sea level, the Mariana Trench is deeper than Mount Everest is tall (5.5 miles).

Mining in the deepest parts of the ocean may not yield minerals companies want. CAP says that the proposed areas in the Marianas do not even have nodule fields of significant commercial value, and alleges that the mining is a pretext for testing prototype equipment for future operations elsewhere.

“This is a really new environmental issue. Up until about a year ago, deep sea mining was science fiction, so the types of people who would be organized on this if it was a public lands issue are not necessarily as organized,” says Villagomez. “So we’re going out there gathering allies, not just pictures of people with Miss Abyss, but also as that collective power to bring to conservation.”

Oh the places she’ll go

Since launching in August, Miss Abyss has already visited about 20 states, gone backstage at a Spin Doctor’s concert, sat beneath the Brooklyn Bridge, and visited the Grand Tetons.

an illustrated pink octopus underneath the brooklyn bridge
Miss Abyss the dumbo octopus in a neighborhood called DUMBO near the Brooklyn Bridge. Image: Center for American Progress/Miss Abyss via Instagram.

Miss Abyss has also met oceanographer Dawn Wright. Nicknamed “Deepsea Dawn,” Wright is the first Black American and 27th human to dive to the bottom of the Mariana Trench. In July 2022, she dove the 6.8 miles below sea level to Challenger Deep at the southern end of the trench.

“She’s [Wright] just a great ambassador to the deep-sea herself,” says Villagomez. “So to see Miss Abyss and DeepseaDawn together was great.”

While Miss Abyss travels the globe for support, the team at CAP continues working at the policy level. The courts could intervene and stop the lease sales, but the situation remains fluid and uncertain. In the meantime, Miss Abyss will continue her journey on social media. 

And as for where Villagomez would like to see Miss Abyss continue to pop up? “I would love for her to visit our national parks.”

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Jonathan the tortoise is 194 years old and thriving. His genes help explain why.

He lived at the same time as Charles Darwin, Queen Victoria, and President Andrew Jackson. He’s a gay icon, who was alive before Thomas Edison patented the lightbulb. At 194 years old, Jonathan the Aldabra giant tortoise (Aldabrachelys gigantea) is the world’s oldest known living giant tortoise and oldest land animal. But what is helping Jonathan stay alive this long? 

Good genes alone are not responsible for Jonathan’s longevity but a lack of genetic wear and tear appears to be a major contributor to his epic lifespan. In a study published today in the journal Science Advances, scientists pinpoint 287 unique gene variants in Jonathan responsible for reducing the usual effects of aging. These variants control some of the body’s key processing, including repairing damaged DNA, reducing inflammation, regulating insulin, and even suppressing cancer. 

Who is Jonathan?

For most of his remarkable life, Jonathan the tortoise has lived on the island of St. Helena, a British Overseas Territory in the South Atlantic Ocean. He arrived from the Seychelles 144 years ago as a fully-grown adult and was given to the governor of St. Helena, and has lived at the governor’s residence ever since.

a black and white photo of four men standing by two giant tortoises
Jonathan arrived in St. Helena as a gift to Sir William Grey-Wilson in 1882, who later became governor of the island. This image was taken around that time, with Jonathan on the left. Image: A.L. Innes

The giant tortoises of the Galápagos and Seychelles islands like Jonathan are the last survivors of animals that used to dominate the ecology of many islands around the world.

“There are few creatures that could tell us more about ageing than the giant tortoises of the Galapagos and Seychelles islands,” Justin Gerlach, a study co-author and biologist at the University of Cambridge, said in a statement. “Working with a really old giant tortoise is such a privilege: you get a sense of the tortoise being your collaborator, not your study subject.”

Jonathan has been featured on the back of St. Helena’s five-pence coin, is also on a postage stamp, and has gained internet fame. In June, an online hoax claiming that Jonathan had died spread.

a giant tortoise on the grass in front of a large house
Jonathan in front of Plantation House on the island St. Helena. Image: Joe Hollins 2013.

Into the epigenome

In this new study, the team also compared Jonathan’s epigenome with those of younger Aldabra giant tortoises. The epigenome is what switches genes on and off. It is a group of chemical compounds that modify the genome and tell it what to do, where to do it, and when to do it. These can then be passed on as cells divide, and to the next generation.

The switches in controlling Jonathan’s DNA repair and metabolism genes were very similar to those found in younger tortoises. This surprised the team since the epigenome usually changes over time. These changes contribute to the aging process and are a major factor when things start to go wrong in older bodies.

“We found that the gene regulators involved in energy production and DNA repair have remained incredibly stable in Jonathan over almost two centuries,” explained Gerlach.

According to the team, this study marks the first time the epigenome of a giant tortoise has been investigated. Studying the genetic mechanisms during mid-life offers insights into extreme lifespans like Jonathan’s.

two giant male tortoises
Jonathan (left) and David (right). The pair live together at Plantation House. Image: Joe Hollins 2019

“Nature has already solved the puzzle of aging in remarkable ways, and Jonathan’s genome provides a blueprint for cellular resilience,” added study co-author Dr. Stephen Clark.

Clark is also the founder of the Kallel Foundation, a non-profit dedicated to understanding aging by studying genetics.  

“Our goal is to take these evolutionary insights and immediately translate them into practical, affordable treatments for everyday people,” Clark added. “Aging is the greatest risk factor for nearly every chronic disease we face, and through the generosity of philanthropic partners, we can democratise access to longevity medicine.”

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World’s largest steam locomotive returns to the rails for special holiday tour

For the first time since 2019, Union Pacific’s Living Legend No. 844 will be hitting the rails with Big Boy No. 4014. These historic locomotives will be together for a special holiday tour this November. 

On November 21, the pair of steam locomotives will run during a fundraising tour from Greeley to Denver, Colorado. The trip will benefit the Make-A-Wish Foundation, with a donation from Union Pacific’s Community Ties Giving Program. The steam duo will also be on display to the public at Denver’s Union Station. Santa Claus and his elves will even be in the terminal handing out limited-edition gifts. Admission to this event is free and open to the public.

Tickets for the holiday fundraising tour to take a ride in vintage passenger cars pulled by Big Boy and No. 844 go on sale to patrons of the Union Pacific Railroad Museum on October 16. The general public can purchase any remaining tickets on October 19. Families can still visit Denver’s Union Station to view the locomotives free of charge.

Nicknamed the “Living Legend,” No. 844 is a famed high-speed passenger locomotive. It was built in 1944 and the last steam locomotive built for Union Pacific. It hauled some of the company’s most recognizable passenger trains, including the Overland Limited, Los Angeles Limited, Portland Rose, and Challenger. No. 844 is also the last Class I North American steam locomotive and never permanently retired from service. Instead, it was reassigned to freight service in Nebraska from 1957 to 1959, when diesel locomotives took over passenger service duties. Unlike nearly every other steam locomotive of its era, No. 844 escaped the scrap yard in 1960 and Union Pacific retained it for special service.

No. 844 was not scrapped in 1960 like other steam locomotives of its class. Image: Union Pacific.
No. 844 was not scrapped in 1960 like other steam locomotives of its class. Image: Union Pacific.

No. 844 will chug alongside a more famous locomotive, Big Boy No. 4014. Big Boy is currently the world’s largest operating steam locomotive and one of only eight remaining Big Boys in existence and the only one still in operation. These powerful locomotives were constructed during World War II to transport heavy equipment to support the war effort. 

Earlier this year, Big Boy drew millions of spectators during a coast-to-coast journey celebrating the United States’ 250th birthday. The first leg began on March 29. Big Boy then traveled to several states including California, Utah, and New York. 

The steam locomotive celebrated the Fourth of July in Philadelphia, Pennsylvania, where the Declaration of Independence was written in 1776. Thousands of train enthusiasts braved temperatures of 102 degrees Fahrenheit (with a real-feel of 112 degrees) to catch a glimpse of the 133-foot-long and 1.2-million-pound train.

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The cubs from Katmai’s ‘Brady Bunch’ blended family are all grown up

To the untrained eye, two female brown bears (Ursus arctos) in Alaska’s Katmai National Park and Preserve look like any other bears. But Bear #609 (Bean) and Bear #620 were raised in Katmai’s historic Brady Bunch-esque blended family.

Between mid-August and October 2022, Bear #910 blended her family with her sister Bear #909’s family. In the process, she adopted her sister’s 2.5-year-old female yearling cub (a one- to two-year-old cub still with its mother), while she herself had a spring cub (a first-year cub that was born over the winter and emerges in the spring). Adoptions like these are exceptionally rare in the wild, and it is believed to be only the second such adoption at Katmai. The behavior has also been observed in polar bears. 

The sisters were frequently seen fishing together with their cubs, teaching them how to fish throughout 2023. That same year, Bear #909’s ovulation cycle began again, and she separated from her offspring Bear #609 (Bean). A study on their family was published in the journal BioOne in 2025. 

a brown bear walking along a beach
Bear #910 walking along the beach. Image: NPS/Cory Cravatta Cory Cravatta

The adopted Bear #609 (Bean) is a female bear, with large oval-shaped ears with slight blonde tips. She has a dark coat with blonde grizzling, and has a fluffy headband by the fall. Bear #690 (Bean) won the Fat Bear Week Junior competition in 2022, and is now considered a fully independent bear.

Bear #620 is Bear #609’s biological cousin and believed to be the daughter of Bear #910 who blended their families. She is identified by a slightly upturned narrow muzzle, tall oval ears, and a semi-prominent hump on her back. During the early summer, her head and mane are a light brown with a reddish blonde and a white chin. By the fall, she sports a more fluffy grizzled fur headband around her head.

According to Katmai naturalist Mike Fitz, it is unclear how being raised with two strong maternal figures will affect their adulthood. Brown bears will often establish a home range that overlaps with their mothers, and a hierarchy in the region develops among related bears along their mother’s line. Those bears within the same matriline may have more tolerance for each other. 

“If #609 and #620 continue to make Brooks River part of their home range, then we will have a special opportunity to watch the growth and maturation of two especially social young female bears in the same place that their mothers make a living,” Fitz explained in a recent video. “Familiarity with each other and the river and other bears who make it their home as well, sharing space with their large, successful mothers, may very well prove to be keys to their survival, longevity, and success.”

We also do not know just yet if members of this historic bear family will be contestants in Fat Bear Week 2026. The bracket will be announced on Friday, September 18.

Most bear mothers generally keep their litters separated, and this year was an example of why they tend to stick to themselves. On Tuesday, July 28, the live-cams captured a young brown bear cub being killed and eaten by an unrelated mother bear (Bear #806). The deceased cub was born this spring, and was one of Bear #909’s cubs. Bear 909 started this season with two cubs, but has now lost both. 

On Sunday, August 2, one of Bear #335’s (also known as Jolly) cubs died, after following three unrelated cubs up a tree. The mother of the cubs already in the tree attacked Bear #335’s cub, who did not survive the encounter. The identity of the mother bear who killed the spring cub was not confirmed. 

Following the first cub’s death, Fitz and park rangers Christine Loberg and Sarah Bruce said that while infanticide by female adults does occur, this is likely the first documented case occurring at Brooks River. While there is no single answer as to why mother bears are killing cubs, some experts suspect bear adoption, food scarcity, and fights for dominance all play a role. 

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Fat Bear Week kicks off September 22

The salmon? Eaten. The days? Shorter. The bears? Fatter. 

After spending the summer eating the fatty pink salmon swimming through Katmai National Park and Preserve in Alaska, it’s time to celebrate the park’s iconic brown bears (Ursus arctos). Fat Bear Week begins on Tuesday, September 22, and here is everything you need to know. 

What is Fat Bear Week?

Think March Madness, just without the basketball and significantly more bears. Fat Bear Week is a single-elimination tournament, where bear enthusiasts from around the world can vote online for their favorite chunky bear. After each round, the bear with the most votes advances until the winner is announced on September 29. According to the Katmai Conservancy, the event began as a one-day event in 2014 with 1,700 votes cast. Only 10 years later, 1.2 million votes were cast from over 100 countries.

The brown bears return to Brooks Falls for the salmon migration every year in late June, where viewers can watch them on explore.org’s livestream. There, they will feast to fatten up for the long winter ahead. By late summer, the nutritious fish will spawn and then begin to die. The bears will then move to the lower Brooks River in September and October to eat the dead and dying salmon near the river’s mouth.

Eating all of this salmon is important because the heftier the bear, the better chance they will survive their long winter hibernation. Despite being the poster species for winter hibernation, bears are not “deep hibernators,” they way that squirrels, bats, and bees are. Bears enter a state called torpor, which is an involuntary state primarily triggered by lack of food. During this time, the bears rely on stored fat reserves for energy. A torpid bear’s eating, drinking, and waste functions will cease, as its body metabolizes these stores it put on over the summer. 

When is Fat Bear Week 2026?

This year, Fat Bear Week begins on Tuesday, September 22, and a winner will be crowned on Tuesday, September 29. 

How can I vote?

Votes may be cast from noon to 9 p.m. EDT (9 a.m. to 6 p.m. PDT and 8 a.m. to 5 p.m. ADT)

from September 22 and 29 at fatbearweek.org.

Photographs comparing the bears from earlier in the summer and later in the summer will be shown, so voters can get an idea of just how much weight the bears put on during their salmon fest. An adult male bear can go from roughly 700 pounds in the early summer to over 1,200 pounds by fall. 

Voters are also encouraged to get familiar with each bear’s life history and the unique challenges they face to survive.

Which bears are competing this year?

The 2026 Fat Bear Week Bracket will be released on Friday, September 18. 

In 2025, Bear #32 (Chunk) took the crown, despite beginning the salmon run with a freshly broken jaw. He was likely injured while fighting with another bear for a mate, but he still managed to catch plenty of fish. Chunk is known for his dominance and size, but also narrow-set eyes, dark fur, a prominent brow ridge, and a distinctive scar across his muzzle. 

a large bear stands near a waterfall
Fat Bear Week 2025 champion Chunk. Image: NPS/ T. Carmack

How can I support Katmai’s bears?

Donations can be made to Katmai Conservancy’s Otis Fund. The Otis Fund is named after Bear #480 (Otis), who won four Fat Bear Week titles before his death around 2024.  All donations made between September 22 and October 3 will be matched by explore.org. 

What happened with the bears this summer?

This year’s livestream featured an example of how wild (and upsetting to humans) nature can be. On Tuesday, July 28, the live-cams captured a young brown bear cub being killed and eaten by an unrelated mother bear (Bear #806). The deceased cub was born this spring and the child of Bear #909, a 10-year-old brown bear. Bear #909 started the season with two cubs, but now lost both. 

On Sunday, August 2, one of Bear #335’s (Jolly) cubs died, after following three unrelated cubs up a tree. The mother of the cubs already in the tree attacked Bear #335’s cub, who did not survive the encounter. The identity of the mother bear who killed the spring cub was not confirmed. 

Following the first cub’s death, naturalist Mike Fitz and park rangers Christine Loberg and Sarah Bruce said this likely the first documented case occurring at Brooks River. While there is no one answer as to why mother bears are killing cubs, some experts suspect bear adoption, food scarcity, and fights for dominance all play a role. 

Additionally, this year also saw the cub with silver-hued fur, a cub who hopefully learned important lesson about porcupine quill safety, the unique fishing stylings of Bear #164 (Bucky Dent), and Bear #284’s (Electra) family who can “walk on water.”

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