New experiments reveal a sophisticated posture-control system hidden inside living wood.Ancient ferns may have helped keep Triassic Europe burning by rapidly regrowing after fires and supplying fresh fuel for the next blaze. Around 201 million years ago, Earth was rocked by the end-Triassic mass extinction. The crisis has been linked to enormous volcanic activity associated with the breakup of Pangea. Those eruptions released huge quantities [...]Scientists have uncovered two surprising forces that help guide how the human brain forms before birth. Before birth, the human brain is shaped in large part by an unusual class of stem cells known as radial glia. These cells help determine which brain cells are produced, when they appear, and how the cerebral cortex, the [...]Researchers have identified a new plant species in western Thailand whose unusual appearance inspired the dramatic name Thismia daemona, or the “devil flower.” A nearly black flower with horn-like projections and flashes of reddish orange has been discovered beneath leaf litter in a mountain forest in western Thailand. The plant cannot photosynthesize, spends most of [...]
Despite major strides in education and conservation efforts, rabies remains a serious public health issue. The Center for Disease Control (CDC) estimates around 90 percent of cases occur in wildlife, but their consequences still reverberate across ecosystems and routinely endanger humans. Combating the viral disease costs the United States over $300 million every year, but the hefty price tag is justified. Contracting one of the oldest known diseases invariably causes severe symptoms like abnormal sensations, violent movements, hydrophobia, and loss of consciousness. Rabies is fatal in virtually every documented case, and still kills around 59,000 people around the world each year.
Once primarily associated with dogs, rabies has since spread to wildlife such as raccoons, skunks, bats, and foxes—making the issue much more difficult to track and control. Since 1995, the United States Department of Agriculture (USDA) has overseen a National Rabies Management Program in cooperation with state and federal departments, university researchers, and other organizations. After over 30 years of work, one of the most preferred mitigation methods is regularly placing oral rabies vaccine (ORV) bait in strategically selected wildlife areas. The easiest way to spread millions of bait blocks across thousands of square miles? Airdrops.
Next month, the USDA will once again begin tossing fishmeal-coated ORV packets from planes throughout the Southeastern states of Virginia, North Carolina, Tennessee, Georgia, and Alabama. These tiny edibles are specifically crafted to target the most prominent rabies variants seen in raccoons, coyotes, and gray foxes.
“The goal is to prevent westward spread of raccoon rabies by creating a continuous vaccine barrier that stays in front of rabies occurrence on the landscape,” a USDA spokesperson recently told FOX Carolina News. The representative added that although the distribution’s scope doesn’t currently include South Carolina, they are “very close to establishing an ORV area in South Carolina counties bordering North Carolina and Georgia in the next few years.”
If all goes as planned, the National Rabies Management Program’s geographic scope will shrink over time as the disease is regionally eliminated. Until then, anyone who accidentally comes into contact with an ORV bait brick shouldn’t worry about contracting the disease. The vaccine inside each brick is proven safe for over 60 animal species, including cats and dogs. If you happen to locate one in a residential area, the USDA recommends to either simply leave it alone, or use gloves to move it to a more remote location for its intended recipients. Always wash your hands thoroughly after handling ORV bait—and try to ignore the pungent odor of fishmeal.
The post It’s almost time to airdrop rabies vaccines again appeared first on Popular Science.
Authors: Elisa Rigosi, Researcher in Sensory Biology, Department of Biology, Lund University and David O’Carroll, Professor of Sensory Biology, Department of Biology, Lund University
One bee has long been regarded as a benchmark for visual performance: the honeybee drone.
These male honeybees (Apis mellifera) have evolved highly specialised eyes for detecting queens during mating flights. They are extraordinarily sensitive to tiny moving objects less than half a degree across. In human terms, that’s like spotting a person more than 250 metres away.
Honeybees have dominated research on bee vision for more than a century. But some of the most impressive visual performances measured in our new study came from rarely studied, solitary species.
While the honeybee lives in massive colonies, most bee species are solitary so must do everything themselves: find food, locate mates, provision their nests. In terms of vision, several of the solitary species we researched outperformed honeybee workers in a number of ways, including the sharpness of images formed by their eyes.
Understanding how these different evolutionary solutions work is important for more than just understanding bee biology. It could provide ideas for nature-inspired technologies, from compact visual sensors to autonomous robots.
With more than 20,000 species worldwide, bees show extraordinary diversity in lifestyle, body size and ecological role. Some live in open environments; others forage in dense vegetation or in dim light at dawn, dusk and even at night.
Such remarkable diversity prompted us to ask the question: how have bees’ eyes adapted to such different lifestyles and visual demands?
Bees see the world through compound eyes made up of thousands of tiny lenses. These odd-looking structures are their main tools to navigate, locate flowers and identify important landmarks.
Our new study of some daytime-active bee species shows that even bees with similar-looking eyes can achieve impressive visual performance in surprisingly different ways.
Male wool carder bees (Anthidium manicatum), for example, spend much of their day patrolling territories and chasing rivals or potential mates through the air. This bee pushes visual sharpness to the limit with its exceptionally small photoreceptors that minimise optical blur. In contrast, honeybee drones have evolved large lenses that maximise sensitivity.
The Australian blue-banded bee (Amegilla) manages to detect small objects and see sharp images just as well without either of these extreme strategies. Instead, it achieves similar visual performance using a different combination of optical design and sampling.
From the outside, the eyes of these bees all look very similar. But when we looked more closely, we found the size of their visual sensors (photoreceptors) differed greatly.
These light-sensitive structures are a bit like the pixels in a smartphone camera. They sit behind the bees’ tiny eye lenses, converting light into electrical signals. Larger pixels capture more light, improving sensitivity, while smaller ones can help preserve image sharpness.
The challenge – for smartphone designers and evolution alike – is balancing these competing demands.
Looking at anatomy tells us how the eye is built, but not how well it performs. To answer this question, we recorded directly from individual photoreceptors in living bees.
We used glass microelectrodes with tips just a few tens of nanometers wide – thousands of times thinner than a human hair. That allowed us, for the first time in these species, to measure the tiny electrical signals that single cells produce when the bees were shown tiny objects on a computer display.
Our results revealed something unexpected. The diminutive Australian blue-banded bee lacks the enormous eyes of a honeybee drone, yet achieved a similar level of sensitivity in its photoreceptors.
At first glance, this seems paradoxical. How can bee eyes built so differently perform so similarly?
The answer is that evolution is not working towards a single ideal design. Different species have arrived at similar visual performance through different combinations of optical design, photoreceptor structure and visual sampling.
Our findings show why it is important to look beyond a handful of familiar species. By studying a wider range of bees, we can better understand how different senses have evolved, leading to a variety of adaptive solutions.
This is true not only for vision but for other traits, including how bees respond to environmental stresses such as heat and pesticide exposure.
Through our research, we are just beginning to appreciate the remarkably different ways of seeing the world that bees have evolved.
Different bee species have evolved different solutions to the challenges of seeing their world. For example, the Australian blue-banded bee is a buzz pollinator, able to vibrate flowers to release pollen in a way that honeybees cannot. This makes it a potentially valuable pollinator of crops such as tomatoes in Australia, where bumblebees are not naturally present.
Such diverse evolutionary solutions may also prove useful to engineers. Designers of cameras, robots and autonomous vehicles face many of the same challenges as bees: how to gather enough visual information while keeping sensors small, efficient and affordable.
Bees and other insects have been a fruitful source of inspiration for artificial vision systems. In our previous work, we developed computational models based on insect target motion processing that turned out to be as robust as alternative engineered solutions, with large benefits in processing efficiency.
We have now translated these models on to an autonomous robot that can pursue moving targets within natural scenes and even into autonomous flying drones.
Unfortunately, as bee diversity declines worldwide, there is a risk that we lose not only species, but the unique evolutionary innovations that have taken millions of years to develop.
This article is republished from The Conversation under a Creative Commons license. Original article.
The post Bees view the world in surprisingly different ways appeared first on Mapping Ignorance.
Ancient teeth suggest humans were using psychoactive betel nuts 25,000 years ago, pushing the history of habitual drug use deep into the Ice Age. Archaeologists from Griffith University have found evidence suggesting that humans were using mind-altering substances far earlier than previously believed. The research team, led by Professor Adam Brumm of Griffith’s Australian Research [...]There’s nothing better than sinking your teeth into a sweet, creamy chocolate bar. Rats think so, too—and they may announce their chocolate-infused joy to the world at ultrasonic frequencies.
Researchers have previously linked ultrasonic rat vocalizations with different emotional and motivational states in the animals, such as in reaction to rewarding stimuli. For example, the rodents vocalize in this way when eating something sweet.
Now, a team of researchers in Japan have discovered that rats emit a particular ultrasonic vocalization while eating chocolate. Their findings are detailed in a study recently published in the journal eNeuro.
To come to this conclusion, the researchers compared ultrasonic vocalizations that rats emitted when they had access to chocolate, with those they made when they didn’t have access to the candy. The team also compared them with a chocolate-free control group of rats. Researchers then used AI to analyze the vocalizations’ acoustic features, identifying a distinct ultrasonic vocalization—officially 40 kHz inverted-U—strongly associated with chocolate snacking.
“When rats eat something delicious such as chocolate, they emit a distinct ultrasonic call that humans cannot hear,” Koshi Murata, a study co-author and researcher at the University of Fukui, said in a statement. “This call drops sharply when the brain’s opioid ‘pleasure’ system is blocked. This suggests that rats may be vocally expressing the enjoyment of eating, offering a new window into whether animals experience pleasure as we do.”
To see if this distinct vocalization was related to the tastiness of food or just eating in general, Murata and colleagues compared chocolate-eating vocalizations with the sounds the rats produced while eating regular food. And while the rats ate similar amounts of both, they emitted significantly more 40 kHz inverted-U USVs while eating chocolate.
In a separate food-choice test, the rats also demonstrated an obvious preference for chocolate: 15 out of 16 rats picked chocolate over the regular food (and can we blame them?). In two experiments, researchers also found that the vast majority of 40 kHz inverted-U USVs were emitted within one second of a feeding event.
“Our discovery suggests that animal vocalizations could serve as a real-time, non-invasive readout of internal emotional states—specifically, how much an animal is enjoying its food,” said Murata. “Such a tool would allow researchers to measure ‘pleasure’ more directly than current methods permit, and could accelerate research into the brain mechanisms that generate positive emotions.”
Understanding more about how the brain processes rewarding experiences could shed light on behaviors like overeating, as well as conditions like anhedonia, or the inability to feel pleasure and a common symptom of depression.
The post Rats make an ultrasonic sound when they eat chocolate appeared first on Popular Science.
Billions of people still suffer from hunger and food insecurity worldwide. Meanwhile, microbial contamination causes a third of global food waste annually, resulting in major economic losses and illnesses. Although antibiotics and pesticides help control contamination, their excessive use can promote bacterial resistance or leave toxic residues.
One alternative uses materials that generate highly reactive forms of oxygen when exposed to light, called photocatalysts, to prolong food freshness. These molecules kill bacteria by damaging their cell components in a process called photodynamic inactivation or PDI. However, current PDI systems rely on energy-intensive lasers and long exposure times because the bacteria’s protective cell membranes block reactive oxygen molecules. As a result, the systems don’t kill bacteria effectively and risk overheating food, affecting its freshness and nutritional value.
Scientists at Zhejiang University in China thought that it would be possible to achieve a PDI system using accessible, free sunlight with the right photocatalyst. Moreover, they also wanted to integrate this photocatalyst into food packaging to combat microbes during storage.
To make the photocatalyst, the researchers mixed water with a glue-like plant fiber that provides structural support, called pectin, and a chemical from plant seeds that supplies phosphorus, called phytic acid. Then they heated the mixture in a sealed reactor at 220ºC (428ºF) for 5 hours to form tiny structures composed of a carbon core surrounded by a phosphorus-rich shell called phosphorus-modified carbonized polymer dots or PCDs.
To incorporate the PCDs into film packaging, the researchers dissolved equal amounts of a plant fiber from konjac, called glucomannan, and another plant-derived molecule, called carboxymethylcellulose, in warm water to form a network of entangled molecular chains. Then, they added 1.5 milligrams of PCD per milliliter to this mixture, which linked the chains together like molecular fasteners. Finally, they added a moisture-binding chemical called glycerin to prevent brittleness. The researchers cast this mixture onto separate Petri dishes and dried them, forming thin, plastic-like PCD films.
To test the films, the researchers placed Escherichia coli bacteria between 2 sterilized film sheets and exposed the samples to either darkness or simulated sunlight for 20 minutes. They then transferred the microbes onto agar plates and incubated them for 15 hours, allowing surviving bacteria to form visible colonies. They compared the number of bacterial colonies with those of untreated samples to calculate the percentage of bacteria the films eliminated in each environment.
Tests under darkness showed that the films eliminated about 60% of the bacteria. The researchers attributed this result to the positive electrical charge of PCDs, which attracts the bacteria’s negatively charged cell surfaces. The electrical attraction stresses their cell membranes, interfering with essential life processes. This result suggested that the films use a separate charge-based antibacterial mechanism apart from PDI, which requires light to work.
Under simulated sunlight, the films eliminated nearly 100% of the bacteria. The researchers identified 2 principal mechanisms causing this. First, the PCDs acted as tiny heaters that generated localized heat, which stretched holes in the bacterial membranes, allowing contents to leak out of their cells through a process called photoporation. Second, the PCDs generated reactive oxygen molecules that could then penetrate the bacteria. Once inside the cells, these molecules irreversibly damage the bacteria’s internal components and genetic material through PDI.
The researchers also investigated whether PCD films could serve as food packaging by using them to wrap fresh strawberries. Compared with conventional nonbiodegradable polyethylene packaging where visible rotting occurred, the PCD films kept the strawberries fresh for more than 4 days by suppressing bacterial growth and regulating moisture levels. When the team tested whether the films were toxic, they found that the films are safe for humans and compatible for food applications. They also buried the films in soil for 24 days and found that they degraded by 78%, demonstrating biodegradability suitable for packaging fresh foods.
The team concluded that PCD films could be a biodegradable food packaging that combines plant-based materials with multiple antibacterial strategies. The films retained antibacterial activity in darkness and became more effective under sunlight through the combined effects of photoporation and PDI. These findings demonstrated that by combining multiple mechanisms into a single material, researchers can create multifunctional food packaging that remains effective across different storage conditions.
The post Harnessing sunlight to fight bacteria appeared first on Sciworthy.
Staff at St. Louis Zoo in St. Louis, Missouri recently opened up a very special delivery in the mail: an overnight shipment of 500 adult Partula snails.
Their journey began at the Detroit Zoo in Royal Oak, Michigan, and it’s not quite over yet. The small invertebrates’ final destination is Tahiti, where they will be released into the wild as part of an international effort to reestablish wild populations of Partula snails.
“The snails are sent ‘priority overnight’ via either FedEx or UPS. The snails are carefully packed using insulating materials and special ‘phase change’ packs to stabilize the temperature inside,” Mark Vassallo, Curator of Amphibians at the Detroit Zoological Society, tells Popular Science. “Currently the Detroit Zoological Society bred snails are taking a pit-stop at St. Louis Zoo where they will be fed a special diet in order to prepare them for the wild.”
Partula snails are small, tree-dwelling native to islands in French Polynesia. In Polynesian cultural heritage, each unique Partula snail shell represents an island. When humans introduced the predatory rosy wolf snail to the region to manage another invasive snail species, it wrecked Partula snail populations.
For decades, the Detroit Zoo has been breeding and raising Partula snails and helping return them to their native habitat by the thousands in Tahiti. In fact, the 500 en route right now were all bred at the zoo. Each of their shells features an orange dot of animal-safe paint that glows in UV light, which identifies them as one of the snails released in 2026. Each year has a different color, and the dots also allow conservationists to easily monitor them in their natural habitat.
This upcoming release is part of an international recovery program that has returned 11 different Partula species formerly deemed extinct in the wild to their native environments, consisting of over 17,000 individual snails. The Audubon Nature Institute in New Orleans, Louisiana, also recently sent 200 Partula snails to Tahiti.
When asked what “success” looks like, Vassallo explains that, “Success for a conservation project can be defined in stages but ultimately, a self-sustaining population with consistent reproduction and very importantly, proper habitat that is protected to sustain that species to allow long term recovery and stabilization of that population.”
Some species of Partula snails are already extinct in the wild, such as Partula nodosa. In the wake of reintroductions of the species, however, experts were excited to observe offspring born in the wild.
The post 500 snails mailed to Tahiti to reclaim their natural habitat appeared first on Popular Science.
Wild condor parents usually make a great parenting team. But when one female California condor (Gymnogyps californianus) in Pinnacles National Park in Central California found herself in the role of a single mother, park biologists stepped in to help.
The condor mother wasn’t able to provide sufficient care and food for her chick while on her own. Field biologists realized that when hunting for food, she returned to the nest less frequently. The chick needed more nutrition to grow and develop appropriately.
“Based on her behavior, she had largely abandoned the nest, and the chick was unlikely to survive without intervention,” a spokesperson for the San Diego Zoo Wildlife Alliance tells Popular Science.
Pinnacles National Park biologists took the chick when it was around one month old and sent him to the San Diego Zoo Safari Park’s California condor breeding facility. There, he’s receiving care in a specialized puppet-rearing program.
“The puppet-rearing program is a specialized care method used to raise young California condor chicks without allowing them to see or bond with human caretakers,” says the spokesperson. “Wildlife care specialists use hand-crafted puppets that resemble adult California condors and completely cover the caretaker’s hands and arms. Caretakers use the puppet’s beak to deliver food directly to the chick, mimicking the way an adult condor parent would feed its young in the nest.”
The chick was named Cayic (pronounced Chai-eech), meaning “strong” in the Mutsun language of the Indigenous people of California’s Central Coast. Thankfully, Cayic is demonstrating normal growth and development, and experts plan on returning him to the wild next fall.California condors are still considered critically endangered, after nearly going extinct.
As for the chick’s father, he had stopped returning to the nest and eventually died while receiving treatment for suspected lead poisoning. Lead poisoning is the greatest cause of death for California condors and a severe obstacle in the species’ recovery. The species is also threatened by the consumption of microtrash.
California condors, or “thunderbirds” for Native Americans, are North America’s largest flying birds. Their wingspan is almost ten feet long, but their mighty reach didn’t keep them from reaching the brink of extinction. During the 1980s, there were fewer than two dozen of them in the wild. In 1986, the U.S. Fish and Wildlife Service put them all in a captive breeding and release program, including at the San Diego Zoo Safari Park. Six years later, the program had bred enough chicks to return the first condors to the wild.
As of the end of 2025, there are 607 California condors in the world, 392 of which are in the wild. One of them is Cayic’s mom.
“The mother may go on to pair with another male, and we hope she will have another opportunity to breed during a future breeding season,” says the spokesperson.
The post Single California condor mother gets help raising her chick appeared first on Popular Science.
Many organisms often set up their homes on sea turtles. Known as epibionts, the most noticeable passengers are usually the algae and barnacles clinging to the marine reptile’s protective shell. Other epibionts include tiny crabs in the Planes genus who frequently hitch rides inside the crevices between a turtle’s shell and body.
Biologists at the Florida Museum of Natural History recently confirmed a surprising addition to crustaceans’ roster of ocean taxis, however. After examining dozens of specimens collected during surveys off Costa Rica’s Pacific Coast, researchers now know that some small crabs will occasionally climb aboard sea snakes. But these aren’t the Planes crabs the biologists expected. As they describe in a study published in the journal Ecology and Evolution, the clawed invertebrates instead belong to three species related to Planes within the same family.
University of Florida (UF) marine herpetologist Joseph Pfaller first noticed one of the suspicious crabs back in 2012 while studying the yellow-bellied sea snake (Hydrophis platurus). More specifically, he was examining the reptiles’ old skin. Sea snakes shed their scales just like their land-based cousins, but they accomplish the task much differently. Without any hard surfaces to slide against, sea snakes coil into loops to generate enough friction to remove the outer epidermal layers.
“When you find a sea snake’s skin, it’s usually in a knot,” Pfaller explained in a UF profile.
After only collecting a couple of snakes, Pfaller soon watched a small crab fall off one of them. He knew the ocean serpents sometimes hosted barnacles or other stationary organisms, but couldn’t recall a similar situation involving crustaceans—so he started paying attention.
Pfaller amassed 371 sea snakes by the end of his expedition, and he identified far more than crabs. Some of the reptiles also hosted shrimps, snails, and even a clingfish. Pfaller and his colleagues assumed no one previously noticed the additions because marine biologists are generally more focused on the yellow-bellied sea snakes themselves due to their colorful appearance, uncommon distribution, and fascinating underwater behaviors.
Technically speaking, most of the crabs weren’t actually crabs just yet. Instead, most of Pfaller’s collection were considered to be in megalopae—a phase between larva and adult life. That said, at least one young crab appeared to belong to the Planes genus.
Although Pfaller stored the preserved specimens at Florida Museum of Natural History, he soon transitioned to focusing on sea turtles instead of snakes. It took a decade before the oddities resurfaced. After casually mentioning the collection to University of Guam crustacean expert Robert Lasley, his colleague couldn’t resist the joke:
“‘Wait! Wait! Wait! Are you saying you have planes on a snake?’” remembered Pfaller, referencing the cult horror movie Snakes on a Plane.
The pair decided to follow up on his specimens by sequencing their DNA, assuming to confirm their Planes suspicions,but results collected by study co-author and UF invertebrate researcher Soma Elefánti weren’t what they expected.
“Honestly, the thought that we could name this study ‘Planes on a Snake’ was enough to get me motivated, but when we got the results, it was evident that something weird and interesting was going on here,” Lasley said.
As it turned out, none of the megalopae were in the Planes genus. Instead, they belonged to other species in the Grapsidae family, whose adult crabs live on Costa Rica’s coastal trees and rocky shorelines. The study authors knew most crabs release larvae into the water, regardless of living on land or in the water when adults. Because of this, they theorized that the larvae that survived long enough to transition into megalopae instinctually started scoping out a more solid habitat.
“They can swim well, but these things are also built to climb or settle onto something,” Lasley said.
The megalopae that eventually ended up on coastal drift lines likely encountered sea snakes, latched on, then were swept back out into the ocean.
“The snakes are just there, and the crabs don’t know the difference,” explained Pfaller.
The reason no adult Planes crabs were found on the snakes can also be explained by their family tree—Planes crustaceans evolved to know better than to try making a home on the reptiles. Meanwhile, these other species in the Graspidae family are still learning. But since these floaters would never make it back to shore, evolution would have likely taught them the hard way.
“It’s not a good idea. These crabs [had] made a poor decision,” said Lasley.
The post Tiny crabs discovered hitching rides on sea snakes appeared first on Popular Science.
The loss of one ancient Alerce tree could wipe out centuries of fungal diversity.For thousands and sometimes millions of years, marine plankton all over the world built their spiral shells in one direction. Then, suddenly, the spirals switched direction at the same time, everywhere, only to switch back again later. These microorganisms are types of foraminifera, or forams. Found in all oceans, from the tropics to high latitudes, they’re among the most abundant eukaryotic…
Login