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cross-posted from: https://lemmygrad.ml/post/11897429

Scientists Capture First-Ever Photos of the Elusive 'Cozumel Dwarf Fox' | PetaPixel

A small gray fox lies on rocky ground, looking back over its shoulder with its mouth open and tongue slightly out. Its large ears and bushy tail are visible, with greenery in the background.

First-ever photograph of a Cozumel dwarf fox taken on September 17, 2023 | Image credit: Rafael Chacón

The Cozumel dwarf fox, a tiny animal so elusive that scientists were unsure whether it even existed, has been photographed for the first time.

Last month, researchers published the first-ever photographs and confirmed sighting of the Cozumel dwarf fox in more than 20 years in the journal Neotropical Biology and Conservation. The images show the adult male dwarf fox on the island of Cozumel, Mexico.

A close-up of a gray fox lying on the ground, looking to the left with its mouth open slightly, showing teeth. The background is a mix of rocks and blurred greenery.

Close up of the Cozumel dwarf fox | Image credit: Rafael Chacón

While the images were only made public recently, the photographs date back to September 2023, when scientists located and safely recovered the Cozumel dwarf fox following online reports of a disoriented animal near the coastal highway on the island’s eastern side. After being held under observation and receiving a full health assessment, it was released into the Laguna Colombia State Reserve in Cozumel, a protected area chosen for its suitability and distance from road hazards.

Although the Cozumel dwarf fox was recovered, released into a protected reserve, and photographed, scientists say little is known about the species.

“The biggest challenge facing the Cozumel dwarf fox is that we still know almost nothing about it, including its remaining population size, distribution, or ecology,” Travis Bayer of Pathos Wildlife says in a statement. “That uncertainty alone is dangerous, because it makes effective conservation extremely difficult”.

A Tiny Animal That is Likely on the Brink of Extinction

The Cozumel dwarf fox is one of the rarest canine animals on the planet and represents a unique population that has inhabited the island of Cozumel for millennia, with subfossil remains suggesting its presence may predate early Mayan settlement.

This extensive period of isolation led to rapid evolutionary divergence and “insular dwarfism.” The Cozumel dwarf fox is estimated to be 60 to 80% the size of its mainland relative, the gray fox. Prior to this rediscovery, physical evidence of the Cozumel dwarf fox was entirely limited to these subfossil remains, and the last second-hand sighting had been reported in 2001.

Despite its long history on the island, the Cozumel dwarf fox has never been formally described or designated as taxonomically unique. Because its habitats in the southern portion of the island are increasingly threatened by land-use change, development, invasive species, and natural disasters, the scientific community considers the dwarf fox to be critically endangered and likely on the brink of extinction.

“One of the most important takeaways from this research is that species can quietly disappear without the world even realizing they are gone,” Bayer explains. “We often think extinction is something dramatic and obvious, but in reality, it can happen gradually and silently, especially for rare species living in remote or understudied habitats.”

Bayer adds: “The rediscovery of the fox is not a conservation success story yet, but it represents a second chance.”

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cross-posted from: https://lemmygrad.ml/post/11897776

Snuffleupagus, a newly described species, is an adorable little predator


S. snuffleupagus, a newly described species of fish, is named after the beloved Sesame Street character, Mr. Snuffleupagus, to which it bears an "uncanny" resemblance.

A small orange fish with hair-like tendrils and a long snout swimming along coral reef.

Solenostomus snuffleupagus, a newly described species of fish, is named after the beloved Sesame Street character, Mr. Snuffleupagus. (David Harasti)

Scientist David Harasti never had any doubt what he would name the tiny orange creature he first spotted on a diving expedition in Papua New Guinea in 2003.

But it would take another two decades for Harasti and his colleague Graham Short to find the elusive fish again, study it, and officially designate it a new species.

Meet Solenostomus snuffleupagus, named after the beloved Sesame Street character, Mr. Snuffleupagus.

"Snuffy for short," Short, an ichthyologist at the California Academy of Sciences and the Australian Museum, told As It Happens host Nil Kӧksal. "The resemblance was quite uncanny."

Short and Harasti have now written a new paper, published in the journal Fish Biology, describing S. snuffleupagus as a new species of ghost pipefish that makes its home along coral reefs, and disguises itself as red algae.

'The awesome power of natural selection'

The fish has quite a few things in common with its namesake — mainly its orange-brown colouring, the long filaments that look like shaggy hair, and its elephant-like snout.

Milton Love, a marine biologist at the University of California’s Marine Science Institute in Santa Barbara, Calif., says the fish's muppet-like appearance demonstrates "the awesome power of natural selection."

"Clearly, all of the morphological features that we find endearing are of some value to the animal," Love, who was not involved in the research, said in email.

"Or, and here is another hypothesis, Gaia created this fish after having one too many of those rum drinks that come with those little umbrellas."

The head of a small orange fish with a long snout and bright yellow eyes.

A snuffy fish photographed by a diver in Tonga. (Darren Rice/Matafonua Lodge)

But its similarity to Snuffleupagus goes deeper than meets the eye.

It's also extremely elusive, much like Mr. Snuffleupagus, who, in his early appearances on Sesame Street, was only ever seen by Big Bird, leading the other characters to mistakenly suspect he was imaginary.

Harasti and Short tried for years to spot a snuffy fish again after that first 2003 sighting to no avail.

Their luck changed in 2021 when some scuba diver buddies started seeing the little creatures on the Great Barrier Reef and got in touch. The scientists headed to Australia to see for themselves, and on their second dive, they found the fish.

"It's an understatement to say that we screamed under water," Short said. "We high-fived, gave each other a hug, and we were just so excited."

An itty-bitty carnivore

In order to describe the fish and confirm it as a previously undocumented species, the scientists looked at CT scans of specimens first collected in 1993 during exhibition to far north of Queensland, Australia, in the Torres Strait.

Short says they were collected alongside several hundred other fish specimens and tucked away until he and his colleague came looking. But even back then, he says ichthyologist Helen Larson, who was part of the expedition, suspected it was a new species.

S. snuffleupagus, like other ghost pipefish, is a cousin of the seahorse.

A tiny orange fish swims in front of a scuba diver's face

The newly described Snuffleupagus fish is smaller than a matchstick. (Darren Rice/Matafonua Lodge)

Using iNaturalist, the citizen science platform, the scientists confirmed sightings of it in Tonga, Papua New Guinea and New Caledonia, suggesting distribution across the southwestern Pacific.

And while it may look like Big Bird's beloved bestie, there are a few significant differences between S. snuffleupagus the fish and Snuffleupagus the muppet.

While Snuffleupagus is famously big — bigger even than Big Bird — S. snuffleupagus is roughly four to five centimetres long, about the size of an airpod.

A large shaggy brown muppet surrounded by dancers

The Sesame Street character Snuffleupagus, pictured here rehearsing for the 2019 Macy's Day Thanksgiving Parade in New York City, is much bigger and less predatorial than its fish counterpart. (John Lamparski/Getty Images)

And while Snuffleupagus would never harm a fly, S. snuffleupagus is a natural-born killer.

"They look adorable, very cute. They're very delicate and slow moving in the water. And it's been assumed that they only eat small crustaceans like small shrimp," Short said.

Not so, he says. The CT scans found tiny fish skeletons in the specimens' stomachs.

"Every fish has a role, and they are either eating or being eaten. It turns out, ghost pipe fish and in particular, snuffy … they're just like other fish," Short said. "They're predators."

Short says the widespread interest in S. snuffleupagus has been a delight, and he hopes it won't be the last fish he brings attention to.

He and his colleague already have their eyes on another species of ghost pipe fish that is known to divers around the Pacific, but hasn't been formally described.

If it works out, they plan to name it after another muppet, but Short wouldn't say which one.

"Not yet, because I need approval," he said.

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spoiler

A research team from ETH Zurich and the University of Zurich (UZH) has developed a novel approach to treating spinal cord injuries: controllable microrobots deliver stem cells directly to the site of an injury, where they promote nerve cell regeneration. In animal experiments, this approach significantly improved mobility.

Spinal cord injuries can have devastating consequences for those affected. Nerve cells in the spinal cord rarely regenerate naturally, while scarring often prevents the regrowth of nerve fibres. Modern therapies attempt to influence implanted stem cells using electrical stimulation to promote the growth of new nerve cells. This approach has several drawbacks: it requires implanted electrodes, and the transplanted cells do not always survive or integrate properly into the existing tissue.

Cells and nanoparticles cleverly combined

Researchers in Zurich are pursuing a new approach, which they have published in the journal Nature Materials. This involves combining therapeutic stem cells with magnetoelectric nanoparticles in such a way that the cells can be guided magnetically to the precise site of an injury and stimulate the stem cells to accelerate repair.

To achieve this, the researchers created a biohybrid microrobot, which combines living neural progenitor cells (NPCs) with a technical component in the form of specially engineered nanoparticles. The NPCs are derived from induced pluripotent stem cells (iPS cells), which are regular body cells reprogrammed in the laboratory to regain stem cell properties. These iPS cells have the potential to differentiate into various types of nervous system cells.

The nanoparticles consist of two layers: an inner layer that responds to magnetic fields and an outer layer that converts this response into electrical signals. By combining these special nanoparticles with the progenitor cells, the researchers fabricate what are known as NPCbots.

A lab the size of a chip

The researchers create the NPCbots in specialised labs on a surface measuring one square centimetre. This process can be illustrated graphically. “We place a reservoir in the centre where we trap the cells. Then we inject the nanoparticles and wait for the two components to bind,” explains Professor Salvador Pané i Vidal of the Multi-Scale Robotics Lab at ETH Zurich.

After just thirty minutes, the NPCbots – each around six micrometres in size – are ready for use. “To scale up fabrication, we operate several lab-on-chip systems in parallel,” explains Hao Ye, senior scientist and the study’s first author. Depending on the test in question, the ETH researchers need hundreds of thousands of microrobots for cell-based studies and several million for animal experiments.

Injured zebrafish swim again

The team tested the NPCbots on zebrafish larvae with spinal cord injuries. The microrobots were injected precisely into the site of the fish’s injury, and electromagnetic fields were generated. For Pané Vidal, teamwork was vital to the experiment’s success: “Stephan Neuhauss and Jingjing Zang at the University of Zurich did extremely valuable work. They enabled us to demonstrate, in a well-characterised regenerative model system, how quickly cells differentiate using our method and how our bots repair the spinal cord.” In just three days, the zebrafish exhibited nearly normal swimming and exploratory behaviour.

The researchers also tested the NPCbots on mice with completely severed spinal cords. Here, too, the results were very promising: after 28 days, the animals’ nerve cells had reconnected at the site of the injury. During this period, the treated mice exhibited increasingly normal movement patterns – their gait, stride length, coordination and exploratory behaviour improved significantly.

This result is particularly significant because, unlike in zebrafish, the mouse spinal cord does not normally regenerate. The treatment was well tolerated by the animals, with no evidence of any adverse effects or immune reactions.

Success through minimally invasive stimulation

These successes were made possible through electrical stimulation of stem cells, greatly enhancing their differentiation after transplantation. In this process, nanoparticles convert magnetic signals directly into electrical impulses that stimulate specific stem cells. When employing NPCbots, researchers need only apply external magnetic fields around the injury site, eliminating the need for implanted electrodes or cables in previous approaches. This is crucial because the spinal cord is extremely sensitive. “Microrobotic guidance makes the treatment more precise and minimally invasive,” Hao explains.

Magnetic fields are particularly well-suited for stimulating stem cells because they can penetrate tissue easily, and their frequency and field strength can be flexibly adjusted to the specific application. Once the progenitor cells have been stimulated and differentiated into nerve cells, the NPCbots essentially dissolve within the tissue. The researchers expect the nanoparticles to be stable and minimally reactive due to their barium titanate coating. Further studies will determine whether and how the particles are degraded or excreted over the long term.

The idea can be expanded as required

The results from animal experiments are extremely promising, but further research will be needed before NPCbots can be tested in humans. “In addition to many clinical aspects, we first need to test which magnetic fields work best in humans and determine the optimal stimulation duration,” Hao explains. Nevertheless, the researchers are already considering further applications: “The reproducible and scalable production of microrobots using our lab-on-a-chip system demonstrates that the platform’s application potential extends beyond basic research,” explains Professor Pané i Vidal. It could also be adapted for other biomedical applications – for example, in cardiology, oncology, wound healing and other targeted regenerative therapies. This could make these treatments safer, more controllable and more effective.

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"Capitalism charging a fortune to cure you? With stuff that has scary side effects?"

spamsus

"Have no fear! Now you can buy a bunch of shit that doesn't work, from us! We're also unregulated as fuck so who knows if this stuff messes up your kidneys."

The worst thing, and anyone who had parents who fell for these scams growing up will know this, is parents who will try to 'cure' their neurodivergent kids with rat butt herb or whatever. Have fun spending your formative years incorrectly medicated!

Sure, yes I know there are natural medicines that work for certain things. But the industry as a whole is so gross and predatory. Every so often they'll 'discover' some ancient remedy so they have something new to market. Selling crystals and sage to very ill people who need real treatment. Exploiting sick people who are desperate for a cure is low as hell and I'm surprised (but not surprised) that they can just sell things that do not do the thing they say they do.

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cross-posted from: https://lemmygrad.ml/post/11869863

This spectacular pit viper was among 11 new species that were discovered in Cambodia’s karsts — ancient limestone cliffs with hidden cave systems. While its official name has not been decided, the “pit” refers to the heat-sensitive organ on its head, which it uses to detect and track down warm-blooded prey.

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This spectacular pit viper was among 11 new species that were discovered in Cambodia’s karsts — ancient limestone cliffs with hidden cave systems. While its official name has not been decided, the “pit” refers to the heat-sensitive organ on its head, which it uses to detect and track down warm-blooded prey. Phyroum Chourn/Fauna & Flora

Conservationists Sothearen Thi and Phyroum Chourn from the charity Fauna & Flora search for reptiles and amphibians deep inside a karst. For two years, the wildlife non-profit surveyed more than 60 caves across western Cambodia in an effort to document life in these unique ecosystems and ensure their protection.

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Conservationists Sothearen Thi and Phyroum Chourn from the charity Fauna & Flora search for reptiles and amphibians deep inside a karst. For two years, the wildlife non-profit surveyed more than 60 caves across western Cambodia in an effort to document life in these unique ecosystems and ensure their protection. Manita Hem/Fauna & Flora

Named after the Hindu god of destruction, Gekko shiva was another unique reptile found in the surveys. It was discovered in early 2025 in a Thai cave temple dedicated to the deity. Researchers warn that its striking appearance makes it a target for the exotic pet trade, and giving it a formal name is the first step toward legal protection.

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Named after the Hindu god of destruction, Gekko shiva was another unique reptile found in the surveys. It was discovered in early 2025 in a Thai cave temple dedicated to the deity. Researchers warn that its striking appearance makes it a target for the exotic pet trade, and giving it a formal name is the first step toward legal protection. Manita Hem/Fauna & Flora

Pablo Sinovas, who led the Fauna & Flora survey team across the karsts, inspects a young reticulated python. This species can grow over 7 metres, making it the world’s longest snake.

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Pablo Sinovas, who led the Fauna & Flora survey team across the karsts, inspects a young reticulated python. This species can grow over 7 metres, making it the world’s longest snake. Manita Hem/Fauna & Flora

This gecko species, found across different karsts, is new to science. It belongs to the Gehyra genus — geckos with powerful claws and sticky toepads. These help them climb almost any surface.

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This gecko species, found across different karsts, is new to science. It belongs to the Gehyra genus — geckos with powerful claws and sticky toepads. These help them climb almost any surface. Hun Seiha/Fauna & Flora

The ornate flying snake glides from tree to tree by flattening its rib cage and twisting through the air like a shimmering ribbon. It is increasingly threatened by illegal trade, as its vivid colors make it popular amongst reptile collectors.

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The ornate flying snake glides from tree to tree by flattening its rib cage and twisting through the air like a shimmering ribbon. It is increasingly threatened by illegal trade, as its vivid colors make it popular amongst reptile collectors. Phyroum Chourn/Fauna & Flora

The Cambodian blue-crested agama was also identified in the surveys. This lizard was only recognized as a new species in 2021, and it can change its vibrant colours when threatened.

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The Cambodian blue-crested agama was also identified in the surveys. This lizard was only recognized as a new species in 2021, and it can change its vibrant colours when threatened. Phyroum Chourn/Fauna & Flora

Karsts are not only ecologically rich but also valued by nearby communities as sacred spaces. Many caves have become Buddhist temples, attracting worshippers and tourists alike.

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Karsts are not only ecologically rich but also valued by nearby communities as sacred spaces. Many caves have become Buddhist temples, attracting worshippers and tourists alike. Phyroum Chourn/Fauna & Flora

Despite their extraordinary biodiversity, Cambodia’s karst landscapes are unprotected, often quarried and blasted for their limestone to produce cement. Fauna & Flora warns that because some species exist only in one hill, destroying a single formation can drive species to extinction — including some we know nothing about yet.

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Despite their extraordinary biodiversity, Cambodia’s karst landscapes are unprotected, often quarried and blasted for their limestone to produce cement. Fauna & Flora warns that because some species exist only in one hill, destroying a single formation can drive species to extinction — including some we know nothing about yet. Phyroum Chourn/Fauna & Flora

Pit viper, flying snake and geckos among new species uncovered in Cambodian caves | CNN

New species uncovered in Cambodian caves

Cambodia’s largely unexplored limestone caves stretch for thousands of miles, are home to countless undiscovered species and host unique ecosystems, with creatures found nowhere else on Earth.

Now, a new survey of caves in the northwestern province of Battambang has uncovered a range of species that are new to science, including a turquoise pit viper, a flying snake, several geckos, two micro-snails and two millipedes.

The viper and three of the newly discovered gecko species are still being formally named and characterized. The other finds have been officially recognized over the course of the biodiversity survey, which explored 64 caves across 10 hills between November 2023 and July 2025, and was published in a report Monday.

Each hill and cave in Cambodia’s rocky karst landscape –– a term for a landscape created when rocks break down, forming large cave springs, sinking streams and sinkholes –– is isolated from the others. Each performs as its own individual “island laboratory” of evolution, holding numerous distinct life forms that have adapted to their niche habitat, according to UK-based conservation charity Fauna & Flora, which led the survey along with Cambodia’s Ministry of Environment and field experts.

A flying snake, documented on the expedition.

A flying snake, documented on the expedition.

“Think of it as their own vignette of biodiversity, where nature is performing the same experiment over and over again independently,” evolutionary biologist Lee Grismer, professor of biology at La Sierra University in California, who supported the survey team, said in a statement.

“We go to these separate places and analyse the DNA of the species, and we see how the experiment has run. Some look alike, some look different, and by analysing this we can get an idea of what the driving forces are behind the way they evolve,” he added.

For instance, while researchers identified one species of the striped Kamping Poi bent-toed gecko, named Cyrtodactylus kampingpoiensis, during fieldwork in 2024, they found four different populations evolving in different ways.

“If we are truly going to conserve the biodiversity on this planet, we need to understand what is there,” Grismer continued. “We can’t protect something if we don’t know it exists.”

Globally threatened species such as the Sunda pangolin, green peafowl, long-tailed macaque and northern pig-tailed macaque were also found in the landscape during the latest survey.

Conservation biologist Pablo Sinovas led the Fauna & Flora team in Cambodia, working with local researchers to get an idea of the terrain during the day and –– the “fun part” –– look for creatures such as snakes and geckos at night, “when they are most active, when they come out of hiding,” he told CNN.

The team would head out after sunset and spend hours traversing “sharp, rocky terrain” with torches, “looking around every crevice, looking around caves in the landscape, rocks, branches, vegetation, really everywhere. It was kind of a nice search party,” said Sinovas, who is now a senior program manager at the charity.

Some caves in the region hold up to one million bats, although the research team did not enter caves with large bat colonies due to health concerns, according to the report.

Karst landscapes make up about 9% of Cambodia’s land area, at 20,000 square kilometers (or 7,722 square miles), said the report, which outlined that “a large portion of this is still unknown to science.”

Fourteen caves that had not previously been surveyed were registered on one karst hill in the Banan district of the Battambang Province.

“There is more exploration to be done,” said Sinovas, adding that they have only “scratched the surface” in terms of the biodiversity that is waiting to be discovered in the ecosystems of the wider landscape in Cambodia.

Laang Spean Cave in Battambang Province, north-western Cambodia.

Laang Spean Cave in Battambang Province, north-western Cambodia.

As well as hosting a range of species, many of the caves are used as shrines, or for meditation and other rituals, and are visited by tourists and pilgrims, according to the report.

Even so, karst habitats are under threat from poorly planned extraction for cement, as well as overtourism, wildlife hunting, logging and wildfires.

“There is growing demand for cement and karst limestone is useful for the making of cement and, so, karst provides a very important raw material,” said Sinovas.

“But, obviously, if you destroy an area where certain species live, and those species don’t live anywhere else, then you would automatically potentially lead to the extinction of species –– in some cases, of species that haven’t even been described yet,” he continued.

“So, we are working with (the) government to ensure that these important areas are better protected,” Sinovas said, adding that there are ongoing discussions regarding “giving this area some sort of protective status, so that they can be preserved into the future.”

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cross-posted from: https://lemmygrad.ml/post/11869711

Scientists Have Been Studying Fire Salamanders for More Than 250 Years. They Just Discovered That the Creatures Glow Under UV Light

Fire salamanders—one of Europe’s most well-researched amphibians—are biofluorescent, which means they can absorb light from an external source at one wavelength, then re-emit it at another

A black and yellow salamander facing the camera in dim light

Fire salamanders are among the most-studied amphibians in Europe, yet until now, no one realized they are biofluorescent. Bernat Burriel-Carranza

First described more than 250 years ago, fire salamanders are among the most-studied amphibians in Europe. Yet researchers are still making new discoveries about these charismatic creatures. Most recently, scientists learned that fire salamanders emit a bluish-green glow after being exposed to ultraviolet light, wavelengths that humans usually can’t see.

It’s the first time the phenomenon, known as biofluorescence, has been documented in the species, researchers report in a study published May 27 in the journal Royal Society Open Science. Though the ecological functions of biofluorescence remain unclear, scientists suspect that the amphibians might use the glow to communicate with one another, select mates or ward off predators.

Biofluorescence occurs when organisms absorb light from an external source at one wavelength, then re-emit it at another. Scientists used to think that only marine creatures and arthropods—a group that includes insects and arachnids—were biofluorescent. But in recent decades, they’ve been finding the trait in more animals, including some reptiles, birds and amphibians.

The underside view of a fire salamander's head

The bright, sparkly pattern is concentrated in the yellow spots on the creatures’ skin. Bernat Burriel-Carranza

“We are in a thrilling period of discovery in terms of biofluorescence in amphibians and other [four-limbed vertebrates],” Jennifer Lamb, a biologist at St. Cloud State University who was not involved with the research, tells National Geographic’s Jack Tamisiea.

Studies like this one, she adds, “help fill some of the gaps in our understanding, both in terms of what species fluoresce and in terms of the mechanisms likely responsible for that fluorescence.”

Against this backdrop, Bernat Burriel-Carranza, an evolutionary biologist at the Natural Sciences Museum of Barcelona, decided to start taking an ultraviolet (UV) flashlight, also known as a blacklight, with him on evening field expeditions. On a rainy night in Spain, he spotted a fire salamander crossing the road and pointed the beam at it. The flashlight revealed a bright, speckled pattern along the creature’s flanks.

Did you know? Biofluorescence vs. bioluminescence

Biofluorescent animals require an external light source to glow, while bioluminescent creatures produce their own light through chemical reactions in their cells.

Common throughout Europe, fire salamanders are small, black-and-yellow amphibians that range from 6 to 12 inches long. These nocturnal critters tend to live in cool, damp forests near bodies of water, where they feast on worms, slugs and other insects. If they feel threatened, fire salamanders can protect themselves via toxins in their skin or by spraying poisonous liquid from glands behind their eyes. They breathe through their skin, can regrow their limbs and tails and give birth to live young.

After the initial field observation in Spain, Burriel-Carranza and his colleagues decided to investigate biofluorescence in fire salamanders further. Between April 2024 and November 2025, they searched for fire salamanders in Spain and Germany, illuminated them with a UV flashlight and took photographs to capture the bright, speckled glow. The fluorescence seemed to be coming mostly from the yellow spots on the creatures’ skin and concentrated along their sides and stomachs.

A black and yellow salamander in grass

Scientists think the yellow splotches might serve as warning signs to potential predators. Andrés Brunetti

Researchers also swabbed the salamanders’ skin to collect samples of their toxic secretions. When they exposed the slime to UV light, it glowed, too, suggesting the biofluorescence may be coming from the glands that produce the poisonous goo.

CW: animal crueltyTo confirm that hypothesis, the team dissected two preserved fire salamanders. When they looked at tissue samples under a microscope, they found fluorescent chemical compounds in the glands and bloodstream, which suggests the substances circulate throughout the creatures’ bodies. That’s something that had previously been observed only in some tree frogs, which use fluorescent compounds known as hyloins to illuminate their translucent skin.

A small foot of a fire salamander

Researchers suspect that the biofluorescence plays a role in communication. Bernat Burriel-Carranza

“We still don’t know what the compound responsible for this fluorescence is, but everything indicates that it is a molecule unknown until now in this species,” says study co-author Salvador Carranza, a biologist at the Institute of Evolutionary Biology in Spain, in a statement. “Identifying it will be key to understanding its origin and function.”

Though humans usually need a UV light to see the salamanders’ blue-green glow, it might be more clearly visible to other animals. Because salamanders are nocturnal and live in dense forests, one possible explanation is that they fluoresce so they can see one another better at night. The researchers say this proposal is supported by the fact that, compared with daylight, full moonlight contains more UV and violet wavelengths, the ones that are absorbed by the animals and re-emitted at different wavelengths. Additionally, the amount of moonlight that reaches the forest floor peaks in the fall, when the salamanders usually breed.

The underside of a fire salamander in UV light

The toxic secretions that fire salamanders produce from their skin also glow under UV light, the researchers discovered. Bernat Burriel-Carranza

Beyond flagging down potential mates, the amphibians might also be using their natural fluorescence as a warning to predators. The scientists think the creatures use their bright yellow splotches as natural “keep away” signs, and because the fluorescence is concentrated in those markings and their toxic secretions, it may help reinforce that warning.

No matter how fire salamanders use their biofluorescence, Burriel-Carranza finds it “fascinating” that such a well-studied species could still hold undiscovered traits, he says in the statement.

“It reminds us that even the most familiar organisms can hide secrets that are only revealed when they are observed with new tools,” he adds.

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cross-posted from: https://lemmygrad.ml/post/11848895

Banner image: Turquoise dwarf gecko. Image © Ardgard Essau via iNaturalist (CC BY-NC 4.0).

How trade bans and local conservation helped save a dazzling blue gecko

Beauty is a curse — at least for the turquoise dwarf gecko of central Tanzania. Between December 2004 and July 2009, demand for this gecko from collectors in Europe boomed, leading to the capture and export of an estimated 40,000 of these striking reptiles from Tanzania.

“I remember when I saw them for the first time [at] a fair, it was about 600 euros per specimen,” or about $700, Dennis Rödder, a herpetologist at the Leibniz Institute for the Analysis of Biodiversity Change in Germany, told Mongabay in a video call. “I think within three or four years, the species appeared everywhere across Europe. You could buy them in every pet shop.”

Turquoise dwarf geckos (Lygodactylus williamsi) grow to a length of 6-9 centimeters (about 2.5-3.5 inches) and are known from only two small patches of forest in Tanzania: The Kimboza and Ruvu forest reserves. These protected areas cover a combined 34 square kilometers (13 square miles). Adult females have a green-brownish color that mimics the leaves of the trees they live in, but the males’ skins are a vivid contrasting blue, one of the rarest colors in nature, meant to stand out and attract females.

Turquoise dwarf gecko (Lygodactylus williamsi). Image © Simon via iNaturalist (CC BY-NC 4.0).

Turquoise dwarf gecko (Lygodactylus williamsi). Image © Simon via iNaturalist (CC BY-NC 4.0).

Active during the day, and so fiercely territorial they evict their young hatchlings from their home trees soon after birth, this species lives exclusively on screwpines (Pandanus rabaiensis), a tree found in Kenya and Tanzania. Standing anywhere from 3-20 meters tall (up to 66 feet), these trees feature long, spiked leaves and a fountain-shaped architecture that provide the ideal habitat for the reptiles, giving them shelter to hide and reproduce, a platform to bask, and a feeding place where water for cooling and insects accumulate.

“It’s the perfect environment for them,” Charles Kilawe, a forest ecologist at Tanzania’s Sokoine University of Agriculture, told Mongabay in a video call. “The leaves of the Pandanus have spines, and it protects [the lizards] against predators like snakes or … eagles.”

But the gecko’s reliance on the screwpine as protection against natural predators has left it vulnerable to another predator: using machetes, poachers cut down large screwpines to grab their helpless resident geckos. The logging to capture these animals was so intense that by 2009, screwpines had gone from covering more than half of Kimboza to only 17.6% of the forest reserve’s area.

That year, researchers estimated that only around 150,000 of these beautiful geckos remained in the wild.

“When I started to work there in 2016, it was difficult to spot them,” Kilawe said.

Location map

In 2009, herpetologist Morris Flecks and colleagues from the Leibniz Institute interviewed one group of gecko collectors from the communities around Kimboza and estimated that they had captured between 32,000 and 42,000 turquoise dwarf geckos from the forest reserve over the previous five years. The researchers noted that this total — which they believed represented at least 15% of the wild population at the time — could be even higher as it didn’t account for many more geckos collected by other groups known to be operating in the forest.

Collection or export of the geckos — or any other wildlife species from a protected forest reserve — required a license, but officials from the Tanzania Wildlife Research Institute told the researchers no such permits were ever issued.

This frenzied collection for the pet trade and the rapid destruction of their already limited habitat led to a steep decline in the geckos’ population size; Rödder, Flecks and other herpetologists recommended that the species should be listed as critically endangered by the IUCN. This was done in 2012. It took another five years before international trade in turquoise dwarf geckos was banned when the species was added to Appendix I of CITES, the global treaty on the wildlife trade.

By this time, the wholesale capture of the geckos in the shadow of Tanzania’s Uluguru Mountains had tapered off; overseas markets were saturated, and while the reptiles remained popular, captive-bred geckos were widely available across Europe, pushing the price of a turquoise dwarf gecko from a peak of $1,500 per specimen to just $40 each.

“Population sizes are back to pre-collecting events. So that’s the good part,” Rödder told Mongabay.

“The not-so-good part is that after a couple of years after our study, there was a wildfire in one of these reserves.”

The white-chested alethe (Chamaetylas fuelleborni) is one of several species that have returned to Kimboza, thanks to restoration efforts involving members of the local community. Image © Zein et Carlo via iNaturalist (CC BY-NC 4.0).

The white-chested alethe (Chamaetylas fuelleborni) is one of several species that have returned to Kimboza, thanks to restoration efforts involving members of the local community. Image © Zein et Carlo via iNaturalist (CC BY-NC 4.0).

Habitat loss due to illegal logging, collection of firewood, conversion of forest to agricultural land, mining, and the growing presence of the invasive Spanish cedar (Cedrela odorata) inside and outside the two forest reserves where L. williamsi is found continue to put pressure on the geckos.

Spanish cedar was introduced to Kimboza in 1960, ironically as a means to relieve logging pressure on native tree species. The idea was that this fast-growing tree, native to the Americas, could provide a reliable source of quality timber and firewood.

The idea was too successful. The exotic cedar, which can grow to a towering 40 m (130 ft), turned out to be very invasive: because it produces seeds twice a year that are dispersed by wind and germinate easily in open areas, the species has taken advantage of gaps and changes to forest structure caused by illegal logging and fires to replace screwpine in many areas.

“By 2016, Cedrela was the most dominant tree in the forest, covering nearly 32% of the big trees area,” Kilawe told Mongabay.

In 2022, Kilawe published a study of Kimboza aimed at determining if turquoise dwarf geckos were directly affected by the presence of Spanish cedars. He found screwpines still thriving in swampy areas and on limestone outcrops, but where a similar survey 40 years earlier found P. rabaiensis in more than half of plots it surveyed, screwpines occurred in barely half the plots Kilawe examined — a severe reduction in habitat for geckos. The presence of cedars, meanwhile, had moved in the opposite direction, found in 16% of plots in 1982, but 52% in Kilawe’s study.

While he found turquoise dwarf geckos just as frequently in screwpines growing under the taller cedars, results from the surveyed plots showed that the number of lizards in screwpines shadowed by dense exotic canopy was considerably lower than in areas where there were fewer cedars or none at all.

Further research is needed to understand what the direct effect of the cedars’ presence on geckos is, but the invasives’ steady expansion into forest areas opened up by fire or tree falls raises fears that cedars will continue to displace gecko habitat. Similar impacts on native biodiversity have been reported from other places where the tree has been introduced, such as Ghana and the Galápagos Islands.

Screwpine (Pandanus rabaiensis) in Morogoro, Tanzania. Image © Andrey Vlasenko via iNaturalist (CC BY-NC 4.0).

Screwpine (Pandanus rabaiensis) in Morogoro, Tanzania. Image © Andrey Vlasenko via iNaturalist (CC BY-NC 4.0).

Today, people from the villages surrounding Kimboza Forest Reserve assist rangers in managing the forest, Kilawe said. Led by Kilawe, they have cut down nearly 100,000 Spanish cedar trees since 2016, and reduced forest fires by around 80%.

They have also planted about 5,000 native trees per year since 2018, working step by step to rebuild the original structure of Kimboza’s forest. Kilawe told Mongabay 10 “ambassadors” drawn from the different villages are paid for their efforts; guiding tourists is another source of occasional income linked to protecting this ecosystem.

“We are hoping that if the removal process continues, in about five years, maybe the forest might be Cedrela-free,” Kilawe said. “It is very important and effective to work with the community in conservation.”

Once caught between the devil and the blue sea, the turquoise dwarf gecko is recovering thanks to these reforestation efforts and the prohibition on trade worldwide. Kilawe said the restoration of Kimboza’s forests has also allowed other animals, such as blue monkeys (Cercopithecus mitis) and birds like the white-chested alethe (Chamaetylas fuelleborni) and the trumpeter hornbill (Bycanistes bucinator) to return to the forest, showing that collaborative hard work can save species and places from the fragile edge of extinction.

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cross-posted from: https://lemmygrad.ml/post/11842509

'Lethally salty' waters hinder rare toad's recovery

Getty Images A natterjack toad sits on a rock in a pool of water with some plant life around itGetty Images

The study found toad survival and size was affected by the salt levels in the water

Salty water could be preventing the recovery of one of the UK's rarest amphibians by making former breeding sites unsuitable for their survival, a study has concluded.

The natterjack toad is found in just a handful of locations.

In Scotland, its only remaining homes are along the Solway Coast, including the RSPB's Mersehead Reserve near Southerness.

Scientists have found that the salt level in water from former breeding sites in south-west Scotland was linked to failed hatching, smaller growth and altered development.

The research is published in the academic journal Ichthyology and Herpetology.

Getty Images A big water pool in a grassy hillsideGetty Images

The study took samples at various sites to check their salt levels

The project was led by Dr Frances Orton, an environmental biologist at Edinburgh's Heriot-Watt University.

"Natterjack toads have declined across the UK, not just in Scotland," she said.

"We wanted to find out why these tiny toads were surviving in the nature reserve in Dumfries and Galloway, but had disappeared from sites along that coast.

"We used anecdotal reports from farmers and local wildlife groups to identify former breeding ponds in Caerlaverock, Southerness and several farms."

The team analysed water samples from Mersehead, where the natterjack toad survives, and other sites.

They measured temperature, pH and salinity and exposed natterjack spawn to water from each of the sites.

Getty Images A natterjack toad sitting on top of grass. We can see just one of its beady eyes, the right one as it is sideways on.Getty Images

Scotland's only remaining natterjack toad colonies are along the Solway Coast

Orton said: "Some of the former breeding sites had such a high level of salinity that no embryos survived to hatching.

"Some weren't as lethally salty, but what we saw there was that the toads were much smaller.

"That doesn't sound like a big deal, but when you're a frog, size really does matter. 95% of tadpoles are eaten by predators.

"For the 5% that make it to the next stage of development, they need to be as big as possible for a chance at survival."

She said the findings could help improve work to revive numbers.

"Until now, a lot of natterjack toad restoration efforts have focused on improving terrestrial habitat, like clearing scrub or controlling vegetation," she said.

"That's still important, but now we know that unless the salinity of the water is tackled, the tiny toads will have no chance of survival."

The biologist added that action needed to be taken soon.

"Amphibians are the fastest-declining vertebrate group globally," she said.

"They've been around for 350 million years, but now species like the natterjack toad are disappearing, quickly.

"They play a huge ecological role as both predators and prey - they feed lots of animal species and, as gardeners will tell you, they eat lots of slugs and midges.

"Natterjack toads are on the verge of extinction and it's vital we understand ways to protect and boost the populations that remain."

Orton and her team conducted the research - supported by the Carnegie Trust and NatureScot - across seven sites in Dumfries and Galloway.

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cross-posted from: https://lemmygrad.ml/post/11831906

Cover image:

Two individuals of Thecacera sesama sp. nov. feeding on a bryozoan. Image credit: Ho-Yeung Chan et al.

Tiny sesame sea slug species discovered in the waters of northern Taiwan | Blog

This tiny nudibranch, which measures less than three millimetres in length, was first spotted by lead author Ho-Yeung Chan during a recreational dive in 2019.

Translucent, speckled, and barely the size of a grain of rice, a new species of sea slug has been identified in the coastal waters of Keelung, Taiwan. Because of its minute size and distinctive black and yellow markings, researchers from National Taiwan Ocean University, National Museum of Natural Science and National Taipei University of Education have named the creature Thecacera sesama.

“Taiwanese divers call it ‘sesame’ in Chinese and it is also small like a sesame seed, hence the name,” the research team explained regarding their decision to honour the local nickname in the scientific nomenclature. This tiny nudibranch, which measures less than three millimetres in length, was first spotted by lead author Ho-Yeung Chan during a recreational dive in 2019.

Thecacera sesama sp. nov. Details of appearance and morphological features, hand-drawn on a tablet PC by Chen-Lu Lee.

The discovery was a stroke of luck that began during Chan’s undergraduate studies:

“During a recreational dive in the summer during the undergraduate study of HY Chan in 2019, he accidentally discovered Thecacera sesama sp. nov. in northern Taiwan waters.”

The Research Team

Despite its unique appearance, the importance of the find was not immediately obvious. In a modern twist on traditional taxonomy, Chan “never realised Thecacera sesama was a new species until he consulted the sea slug expert ‘Hsini Lin teacher’ on Facebook.”

Living specimens of Thecacera sesama sp. nov. Image credit: Ho-Yeung Chan et al.

Documenting the species proved to be a significant logistical feat due to the volatile environment of the Keelung coast. The research team noted that the most challenging part of the study was the unique weather conditions of the region.

Taiwan experiences frequent typhoons in the summer and large waves during the winter monsoon season, with sea temperatures often dropping below 16 degrees Celsius. These factors mean that diving for nudibranch research is only possible for about four months of the year, making sightings of such tiny creatures entirely a matter of chance.

Living specimens of bryozoan with Thecacera species. Image credit: Ho-Yeung Chan et al.

The life of T. sesama is remarkably focused, as the researchers observed that the species exhibits only four primary behaviours: feeding, searching, mating, and laying eggs on bryozoans, which are tiny aquatic invertebrates often called “moss animals”. Interestingly, the specific bryozoan that T. sesama calls home may itself be a species new to science.

From a broader ecological perspective, these vibrant molluscs play a vital role in the marine environment:

“Nudibranchs are one of the key players in the marine food web. They are extremely colourful and can be spotted on coral reef ecosystems. However, many nudibranchs are very small in size and are extremely difficult to spot underwater with the naked eye.”

The Research Team

The researchers believe that the discovery of T. sesama is just the tip of the iceberg for Taiwanese marine biology. Because many species are so small, many more are likely awaiting discovery and formal study. The full research on Thecacera sesama was published in the open-access journal ZooKeys on 11 May 2026.

Original source:

Chan H-Y, Lee C-L, Chen W-C, Chang C-H, Shao Y-T, Pang K-L (2026) Thecacera sesama sp. nov. (Nudibranchia, Polyceridae) from Taiwan, evident from morphology and phylogenetic analyses of the 16S rDNA and cytochrome c oxidase I gene. ZooKeys 1279: 269-284. https://doi.org/10.3897/zookeys.1279.184298

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cross-posted from: https://lemmygrad.ml/post/11831859

Hidden in plain sight: the race to discover new species before they’re gone

When most people imagine scientists discovering new species, they probably still picture an expedition into the unknown.

A naturalist travels somewhere remote, perhaps on a wooden ship, and traipses through the jungle to encounter an animal or plant never before described by science. The intrepid explorer brings back specimens or observations to a museum, where they can be compared, named and described.

There is some truth to this stereotype. Between 1854 and 1862, scientist Alfred Russel Wallace travelled through the Malay Archipelago, discovering animals and insects unknown to Western science. This led him to the theory of evolution by natural selection, contemporaneously with Charles Darwin.

Antarctica had its own era of discovery. In 1840, scientists on a French expedition encountered what we now know as Adélie penguins. Imagine seeing penguins for the first time: strange black-and-white birds waddling over the ice, sliding on their bellies, leaping from freezing seas.

Of course, “discovery” is a loaded word. Many animals and plants described by Western science were already known to Indigenous peoples and local communities. What changed was their entry into the formal scientific naming system – the global process by which species are compared, classified and recognised.

Today, scientists are still finding new life in remote places and hidden inside the DNA of animals we thought we already knew.

We still explore unknown worlds

Scientists still discover species this way: by probing Earth’s nooks and crannies and travelling to remote places to study what lives there.

Last year, I was onboard the scientific vessel R/V Falkor (too) in Antarctica’s Weddell Sea, where one scientific team was searching for seafloor methane seeps.

These are not just geological curiosities. Methane seeps create unusual habitats that harbour strange communities of life fuelled not by sunlight, but by chemicals rising from below. Scientists have already found new microbial diversity at Antarctica’s first known active methane seep.

Not all hard-to-reach worlds are underwater. In Papua New Guinea’s Southern Fold Mountains, camera traps captured a shy, ground-dwelling bird slipping through rugged limestone forest. Scientists described it as a new species in 2025, the hooded jewel-babbler.

But there is another kind of discovery happening too.

White microbial mats underwater are telltale signs of seeping methane. Andrew Thurber, CC BY-ND

Hidden species in familiar animals

Some species are not hidden because they live at the bottom of the sea or deep in a mountain forest. They are hiding in plain sight.

Gentoo penguins are a good example. With their bright orange bills and comic waddle, they are familiar to anyone who has visited Antarctica. To most observers, they are simply “gentoos”.

But our new research shows gentoo penguins are not one widespread species, but four. Our 2020 study first showed major genetic and physical differences between gentoo penguins from different islands.

Now, using whole genomes – the complete set of genetic instructions inside an animal – and ecological modelling, we found these penguins are not just separated by distance, but have adapted to different Southern Ocean worlds.

A large colony of Gentoo penguins on the ice with the ocean behind.

Gentoo penguins on Cuverville Island, Antarctica. David Stanley/flickr, CC BY-ND

Learning to see in higher resolution

Discoveries like this are often called “hidden” species. They look very similar to their relatives, but if we study their DNA, body measurements, behaviour and ecology, it’s clear they are separate species.

Species discovery has always depended on the tools available. Early naturalists relied on what they could collect: feathers, skins, eggs and bones. These museum collections are like time machines and remain incredibly important.

Today, whole genomes tell us if animals have different coding. Ecological models show whether animals live in different environmental conditions. Mathematical approaches test whether groups are evolving independently.

In other words, we are learning to see biodiversity in higher resolution.

This sharper view is changing how we understand familiar animals. For a long time, giraffes were considered one species, but genetics suggests they are four. My own work on forest birds in Madagascar found a new species of Newtonia bird.

The Tapanuli orangutan is a powerful example. This Indonesian great ape from Sumatra was described as a new species in 2017, based on genomic, anatomical and behavioural evidence. It was extraordinary to recognise a new great ape in the 21st century, and sobering to realise fewer than 800 may remain.

Again and again, the message is the same. The natural world is more complex than we know. And sometimes, by the time we recognise that complexity, a species may already be in deep trouble.

An orangutan sits in a leafy tree.

The Tapanuli orangutan is a species of orangutan restricted to South Tapanuli in the island of Sumatra in Indonesia. It is one of three known living species of orangutan. Prayugo Utomo/Creative Commons, CC BY

Why names matter

Taxonomy – the science of naming and classifying life – can sound like an old-fashioned labelling exercise. But it’s how we map life on Earth.

Conservation laws, threatened species lists and monitoring programs usually work at the species level. If several species are mistakenly treated as one, a declining species can be hidden inside a larger group that looks secure.

As we stand at the precipice of Earth’s sixth mass extinction, this has never been more important.

Recognising hidden biodiversity does not solve conservation problems by itself. But it helps us ask better questions. Which species are increasing? Which are declining? Which have not been counted for decades?

These questions are urgent, because we are racing to understand biodiversity while climate change and habitat loss reshape life on Earth.

Even now, in an age of satellites and genome sequencing, Earth still has secrets. Not only in the most remote places, but in the first animals we learn to recognise as children: penguins, giraffes, orangutans.

The closer we look, the more life reveals itself. Our task now is to keep looking and protect the richness that was there all along.

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https://sci-bot.ru/

kinda like perplexity with scientific papers in sci-hub database, what it writes is irrelevant but pulled citations are neat

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cross-posted from: https://lemmygrad.ml/post/11799050

Banner image of a koala by Bernard Spragg. NZ via Flickr (CC0).

Australia has the money to protect nature. It just isn't spending it, expert says

“I think the international community really does need to put more pressure on Australia to do better,” says Euan Ritchie, a professor of wildlife ecology and conservation at Deakin University in Australia, in a recent episode of Mongabay’s Newscast.

From animals like kangaroos, koalas and platypuses, to plants like waratah, kangaroo paw and climbing heath, Australia has exceptionally high biodiversity, with a unique assemblage of wildlife found nowhere else on the planet.

The Australian government claims the country is on track to meet many of its targets under the Kunming-Montreal Global Biodiversity Framework, the landmark agreement that aims to halt and reverse the decline of biodiversity, and ensure the sustainable use of biodiversity equitable sharing of benefits, among other goals, by 2050.

However, Ritchie, who’s also the president of the Australian Mammal Society and a councilor for the country’s Biodiversity Council, argues that “Australia is failing miserably” on all those measures. This is despite Australia being one of the wealthiest nations on Earth in terms of GDP per capita, with a “huge number of really knowledgeable scientists,” he tells Newscast host Mike DiGirolamo.

“If we look at the number of threatened species in Australia, it’s more than 2,200 now, and that list continues to increase,” Ritchie says. “We have ecosystems that are collapsing, 17 in total within Australia and two more further south into sub-Antarctic and Antarctic regions that are collapsing.”

The iconic koala (Phascolarctos cinereus) is also now endangered in the states of Queensland and New South Wales, and in the Australian Capital Territory (ACT), he adds.

Ritchie and other researchers argue that just 1% of Australia’s annual federal budget, or about A$7 billion ($5 billion), would help save the country’s threatened species and protect ecosystems. However, Australia’s latest annual budget allocates only 0.06% to nature conservation — and this is expected to decline in the future.

At the same time, the government is estimated to spend more than A$26 billion ($19 billion) annually to support or subsidize harmful industries like fossil fuels, DiGirolamo says.

One of the government’s strategies to finance nature protection is to create a “nature repair market,” a voluntary biodiversity market, where industry and private players can earn biodiversity certificates.

A biodiversity market would be very complex to navigate and get right, Ritchie says. Instead, he says Australia should just pony up the money for conservation, which he says it can “afford to [at] a much larger degree today.”

Surveys by the Biodiversity Council also show that 95% of Australians polled support the increased government spending on the environment.

“Australia is a sovereign nation. It’s really rich. If we want to fund something that we think is really important, the government could literally do that today,” Ritchie says. “It’s just a case of whether they have the political appetite to do that.”

Listen to the full conversation with Euan Ritchie here.

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When they’re being eaten, bean plants release chemicals that draw in parasitic wasps.

https://www.science.org/doi/10.1126/sciadv.aec3229

A plant immune receptor mediates tritrophic interactions by linking caterpillar detection to predator recruitment

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cross-posted from: https://lemmygrad.ml/post/11782002

New miniature bright-orange toadlet found in southern Brazil and named after Lula

In a small stretch of the Atlantic Forest in southern Brazil lives a bright-orange species of frog that’s new to science, researchers report in a recent study. The miniature amphibian measures just over a centimeter long, less than half an inch, or the length of an average fingernail.

The team has named the toadlet Brachycephalus lulai, in honor of Brazil’s president, Luiz Inácio Lula da Silva.

The genus Brachycephalus, also called flea toads or saddleback toads, are all tiny and live among leaf litter in Brazil’s Atlantic rainforest. Of the 42 known species, 35 have been described since 2000.

Individuals of the latest species to be described, B. lulai, were found hidden in the leaf litter of the montane Atlantic Forest at two nearby sites on the southeastern slopes of Serra do Quiriri in the state of Santa Catarina, southern Brazil.

The researchers collected 32 individuals and compared different features of the frogs, including their DNA and vocalizations, with those of other Brachycephalus species. Their analysis showed that it was indeed a new-to-science species.

B. lulai has a bright-orange body dotted with tiny green and brown spots. Males measure just 8.9-11.3 millimeters (0.35-0.44 inches) in length, while females are slightly larger at 11.7-13.4 mm (0.46-0.53 inches). The males produce a very distinct call to attract females that’s unique to the species, the researchers found.

Currently, the sites where B. lulai was found appear to be intact, without any significant threats. As such, the researchers suggest the species be categorized as least concern under the IUCN Red List classification.

“The new species occurs in highly preserved forests that are very difficult to access, which means it is not threatened with extinction,” Marcos R. Bornschein, study co-author from the Institute of Biosciences at São Paulo State University, told Popular Science. “It is one of the few Brachycephalus species that are not threatened, which is very reassuring for us.”

However, “it is essential to continue systematically monitoring this scenario,” the researchers write. This is because the broader Serra do Quiriri range — which includes threatened frog species like B. quiririensis, B. auroguttatus, and Melanophryniscus biancae — faces impacts from regular burning of grasslands, cattle grazing, mining, invasion of pine trees, and development for tourism.

Banner image: The newly described Brachycephalus lulai. Image courtesy of Luiz Fernando Ribeiro.

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cross-posted from: https://lemmygrad.ml/post/11752742

How homing pigeons keep navigation simple when winging their way home together

homing pigeon

Credit: Altaf Shah from Pexels

When it comes to flocking together, homing pigeons use a simple strategy to find better ways home, according to a recent report. The study, published in the journal eLife, suggests that homing pigeons use simple route averaging when navigating as a group. eLife's editors say the work addresses an important question, and provides compelling evidence based on multiple models and data on how homing pigeons can generate social routes from solitary ones.

The findings open avenues for future research to investigate the evolution of the mechanisms used by homing pigeons and other social animals when deciding on the best route to travel.

How pigeons pick their routes

How animals navigate complex environments depends on their cognitive abilities. When traveling in groups, some animals pool individual information to improve their navigation. This can be achieved by following experienced leaders, which requires recognizing the experts of the group, or by using simpler mechanisms, such as the "wisdom of crowds" principle, which averages the routes of all individuals. These strategies therefore range from cognitively complex to simple, but their prevalence or interplay in nature remains unexplored.

"This is where the homing pigeon comes in: as a social species that has been studied extensively for their ability to develop and recall routes, these birds are an ideal model organism for studying navigational strategies," says author Shoubhik Banerjee, a Ph.D. student in senior author Albert Kao's lab at the University of Massachusetts Boston (UMass Boston), US. Banerjee and Kao conducted the study with Postdoctoral Researcher Fritz Francisco, also a member of the Kao Lab.

A previous study published in 2017 showed that pairs of experienced and naïve homing pigeons could continuously improve their homing routes over the course of the experiment. The study proposed the key driver to be cumulative cultural evolution (CCE), where chains of birds improve their routes by exploring different options and choosing better ones. However, a detailed mechanistic understanding of how these route improvements emerge is still lacking.

"Building on that study, we aimed to investigate the mechanisms that pigeons use to improve their route efficiency and whether those mechanisms fall under the criteria required for CCE," Banerjee adds.

Inside the experimental design

The previous work involved creating "chains" of birds, similar to a game of telephone, and allowing them to fly back home repeatedly from a release site 8.4km away. Each chain was composed of five "generations" and included an experienced bird that knew about the homing task from the previous generation, paired with a naïve bird that lacked this information.

At the end of the generation (12 flights), the experienced pigeon was replaced with a new, naïve pigeon that traveled with the remaining, now-experienced bird. Working as control groups, solo and fixed pairs of birds carried out the same number of flights as the experimental group (a total of 60 flights). The study found that the experimental chains of birds significantly outperformed both the solo and fixed pair controls by the end of the fifth generation—a result attributed to CCE.

How homing pigeons keep navigation simple when winging their way home together

Illustration of the hypothesized social learning strategies. Credit: eLife (2026). DOI: 10.7554/elife.108054.3

Testing different learning strategies

Banerjee, Francisco and Kao set out to explore which navigation mechanism is necessary and sufficient to replicate those experimental results. They developed seven plausible learning mechanisms, categorized into three types with increasing cognitive complexity.

The first type represents the simplest process, where birds have no knowledge of their partner's level of experience or performance, and includes only the averaging strategy. The second type assumes that birds can recognize the more experienced individual in the pair and maximize their performance using this knowledge. And the third type introduces the highest level of cognitive complexity, which requires birds to actively evaluate their individual or paired performance, aligning with the mechanistic criteria required for CCE.

The team then compared the results of the seven mechanisms with the experimental data to identify which strategies are most likely to be used by real birds. In particular, they explored whether the cognitive requirements of CCE are necessary for the observed improvement in navigation ability.

Simple averaging comes out on top

They found that all of the strategies resulted in route improvements, regardless of their underlying complexity, which suggests that a wide range of decision-making mechanisms can lead to navigational improvements—not just the ones compatible with the definition of CCE. However, when they combined the results with those from a social weight analysis, they found that the experimental data aligned best overall with the simplest strategy: averaging individual routes.

"We show that an improvement in route efficiency alone is not sufficient evidence for cultural transmission, as the experimental birds did not demonstrate some of the criteria of CCE," says author Fritz Francisco. "This could be due to the wisdom of crowds improving routes 'for free' without placing additional cognitive load on the birds. On average, birds in this experiment influenced each other's routes equally, disregarding any differences in experience, which raises broader questions about which social learning mechanisms truly align with the requirements for CCE."

What this means for future research

The team further observed that mixed strategies, while not supported by the experimental data, theoretically combined advantages from both averaging and active selection of better routes, resulting in even greater performance.

"Our results therefore pave the way for future studies to investigate the evolution of social learning and trade-offs among the different decision mechanisms that may be available to animals in the wild," concludes senior author Albert Kao, Assistant Professor and Principal Investigator at UMass Boston.

"For this navigation task, simple averaging is sufficient to explain the experimental results in homing pigeons, but other tasks may be less amenable to the wisdom of crowds—there's a lot of complexity in this area. It would be interesting to explore how collective navigation strategies evolve in different contexts, taking into account, for example, typical group sizes, error rates, and how many times a task is repeated, to better understand social decision-making in homing pigeons and other animals."

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According to the theory of special relativity it IS possible to view two objects moving faster than the speed of light relative to each other. You may think this is not the case but, let me explain. I saw this get confused in a lemmy thread and wasn't setup to post there so I'll clarify here for the interested.

Consider the following: observer A sees a craft B moving right at 0.6c, and another craft D moving left at 0.6c such that they are on a collision course.

B------> <------D

          A

what I'm asserting is A does observe B and D moving at 1.2c relative to each other. The Lorenz transformation is not needed! People get tripped up, but the setup gives away the answer. A sees nothing moving faster than c relative to A so there is no violation of theory.

Special relativity becomes relevant here when determing what is observed in reference frames other than ones own, i.e. B or D. Based on what A sees, it seems like B should see D moving at 1.2c , but applying the lorenz transformation to get B's perspective we see that it doesn't, and everything is seen as slower than c.

B observes A moving at 0.6c, and D at something like, idk, 0.85c (length contraction along the axis of travel is especially relevant here).

   B <---------D

<------A

Just as easily this setup could involve objects moving away from each other and could represent distant objects being pushed away from eachother by the expansion of the universe. The neat thing there is that once they're far enough to cross the horizon above c, they'll never see each other because the light isn't fast enough to cross the gap, so conventiently a violation still isn't observed! wowee

https://en.wikipedia.org/wiki/Observable_universe

light emitted by objects currently situated beyond a certain comoving distance (currently about 19 gigaparsecs (62 Gly)) will never reach Earth.

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cross-posted from: https://lemmygrad.ml/post/11751324

Study clarifies conditions for amphibian species richness on marine islands

Ecology

Study clarifies conditions for amphibian species richness on marine islands

Analysis of data from over 5,000 territories and 1,924 species of toads and frogs shows that two of the main theories about the biodiversity of plants, birds, and mammals in these habitats do not explain the richness of anuran amphibians on their own.

Ecology

Study clarifies conditions for amphibian species richness on marine islands

Analysis of data from over 5,000 territories and 1,924 species of toads and frogs shows that two of the main theories about the biodiversity of plants, birds, and mammals in these habitats do not explain the richness of anuran amphibians on their own.

The Brazilian white-edged tree frog (Boana albomarginata) lives on the mainland and on islands, but the island populations are much larger than the mainland populations (photo: Raoni Rebouças/IB-UNICAMP)

By André Julião | Agência FAPESP – A Brazilian study published in the journal Ecography indicates that the biodiversity of anuran amphibians (toads and frogs) on islands is determined by factors encompassed in two previously opposing theories.

“Biodiversity models that consider island size, distance from the mainland, and productivity [of organic matter per area] have been confirmed with relative success for plants, birds, and mammals, but they hadn’t yet been tested with anuran amphibians, which can’t tolerate salinity and therefore face an insurmountable barrier in the sea,” says Raoni Rebouças, first author of the study, which he conducted as part of his postdoctoral research at the Institute of Biology of the State University of Campinas (IB-UNICAMP) with a fellowship from FAPESP.

To verify whether the models applied to anuran amphibians, the researchers compiled data from over 5,000 marine islands worldwide. Size, distance from the mainland, and climate were among the factors taken into account. The database also included information on the ecological characteristics of 1,924 anuran amphibian species found on marine islands.

The researchers analyzed the number of species on each island, as well as other measures of diversity. These include functional or ecological niche diversity, which considers whether a species is terrestrial, aquatic, arboreal, or fossorial (meaning it lives underground), and phylogenetic diversity, which measures how many evolutionary lineages exist in the area.

“If there are 200 species on an island, but they all belong to the same family and are all aquatic, then there’s high species richness, but low phylogenetic and functional diversity,” explains Matheus Moroti, co-author of the article and a postdoctoral researcher at IB-UNICAMP funded by FAPESP.

In addition to the global analysis, which included all islands and species, the researchers analyzed the biodiversity of anuran amphibians according to climate, distinguishing between tropical and temperate regions.

“Our results show that distance from the mainland, size, and productivity are important for explaining the diversity of anuran amphibians on islands, but their relevance differs depending on the climate [tropical or temperate] and the diversity being considered – whether it’s species richness, functional diversity, or phylogenetic diversity,” says Moroti.


Mantella baroni is one of more than 300 species of anuran amphibians in Madagascar, a large island off the southeast coast of Africa (photo: Leslie Poulson/Creative Commons license via Raoni Rebouças)

Complementary theories

According to the theory of island biogeographic equilibrium, developed based on two papers by Robert MacArthur and Edward O. Wilson, one from 1963 and the other from 1967, the larger the island and the shorter the distance to the mainland, the greater the species richness. This is because species can easily migrate between islands, and larger islands have more space to support many individuals.

On small islands far from the mainland, migration rates would be lower and extinction rates higher, resulting in lower diversity. Subsequently, the theory was tested and confirmed for various groups.

“But for those that can’t tolerate salt, any marine island is distant. That’s why we had to test this theory with anuran amphibians,” recalls Rebouças.

Another important theory regarding island biodiversity considers a factor overlooked by MacArthur and Wilson: the amount of energy available for species to live and evolve on an island, regardless of its size.

Proposed by David Wright in 1983, the species-energy theory suggests that the availability of energy in the form of organic matter productivity per area alone determines diversity on islands.


: Islands seen from Ubatuba, on the coast of the state of São Paulo. Island environments influence amphibian biodiversity differently than they do other animals and plants (photo: Raoni Rebouças/IB-UNICAMP)

Thus, islands of the same size can have different species richness depending on their productivity. The greater the energy produced, the greater the capacity to support a large number of individuals.

“A good example is the world’s largest island, Greenland. Covered in ice for much of the year, it has no frog species. Meanwhile, the second-largest, Borneo, has over 400,” Rebouças explains.

After cross-referencing the available data, the researchers concluded that neither theory alone explains the diversity of anuran amphibians on islands. Rather, both theories are complementary, each providing a better explanation depending on the type of biodiversity measured (species, functional, or phylogenetic) and the climate regime (tropical or temperate).

For example, when considering species and lineage richness, global and tropical data point to a strong correlation with island size. However, in temperate regions, this relationship is weak, as seen in Greenland.

Functional diversity, or the diversity of ecological niches such as terrestrial, aquatic, arboreal, and fossorial, is closely linked to climate when considering the entire world and temperate regions. However, the relationship is weak in tropical regions, which do not depend as much on climate for different niches.

Future studies should examine historical factors influencing diversity on islands. Additionally, a finer-grained analysis could be conducted that includes river islands and considers the extent of water bodies present on the islands.

This study received support from FAPESP through three projects (16/25358-3, 19/18335-5, and 20/12658-4). Two of these projects were part of the Research Program on Biodiversity Characterization, Conservation, and Sustainable Use (BIOTA-FAPESP).

The article “Environmental and geomorphological drivers of frog diversity on islands worldwide” can be read at nsojournals.onlinelibrary.wiley.com/doi/10.1002/ecog.07818.

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