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Carnivorous crocodile-like monsters used to terrorize the Caribbean

How did reptilian things that looked something like crocodiles get to the Caribbean islands from South America millions of years ago? They probably walked.

The existence of any prehistoric apex predators in the islands of the Caribbean used to be doubted. While their absence would have probably made it even more of a paradise for prey animals, fossils unearthed in Cuba, Puerto Rico, and the Dominican Republic have revealed that these islands were crawling with monster crocodyliform species called sebecids, ancient relatives of crocodiles.

While sebecids first emerged during the Cretaceous, this is the first evidence of them lurking outside South America during the Cenozoic epoch, which began 66 million years ago. An international team of researchers has found that these creatures would stalk and hunt in the Caribbean islands millions of years after similar predators went extinct on the South American mainland. Lower sea levels back then could have exposed enough land to walk across.

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© By Ghedoghedo, CC BY-SA 3.0

Some flies go insomniac to ward off parasites

Have you ever pulled an all-nighter because of anxiety? Found yourself doomscrolling on your phone when you should have gone to bed hours ago? Purposely downed too many cups of coffee at three in the morning? There are some insomniac flies who would like a word.

It appears that fruit flies that spend their days lazily buzzing through the lush orchards and rainforests of Queensland, Australia, live in paradise. That changes at sunset. After dark, the flies are plagued by the Gamasodesqueenslandicus mites, which can attach themselves like ticks and literally eat the flies alive in their sleep. Researchers led by University of Cincinnati biologist Joshua Benoit have now discovered that flies that have had enough of the mites will stay awake at the expense of their health.

These mite-resistant flies drain their nutrient reserves to stay up all night, making them more susceptible to starvation. Insomniacs consumed more oxygen and were generally more active than non-resistant flies; they also experienced changes in gene activity related to their metabolisms.

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© Joao Paulo Burini

Lichens can survive almost anything, and some might survive Mars

Whether anything ever lived on Mars is unknown. And the present environment, with harsh temperatures, intense radiation, and a sparse atmosphere, isn’t exactly propitious for life. Despite the red planet’s brutality, lichens that inhabit some of the harshest environments on Earth could possibly survive there.

Lichens are symbionts, or two organisms that are in a cooperative relationship. There is a fungal component (most are about 90 percent fungus) and a photosynthetic component (algae or cyanobacteria). To see if some species of lichen had what it takes to survive on Mars, a team of researchers led by botanist Kaja Skubała used the Space Research Center of the Polish Academy of Sciences to expose the lichen species Diploschistes muscorum and Cetrarea aculeata to simulate Mars conditions.

“Our study is the first to demonstrate that the metabolism of the fungal partner in lichen symbiosis was active while being in a Mars-like environment,” the researchers said in a study recently published in IMA Fungus. “X-rays associated with solar flares and SEPs reaching Mars should not affect the potential habitability of lichens on this planet.”

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© Martin Harvey

Newly hatched hummingbird looks, acts like a toxic caterpillar

The white-necked jacobin (Florisuga mellivora) is a jewel-toned hummingbird found in the neotropical lowlands of South America and the Caribbean. It shimmers blue and green in the sunlight as it flits from flower to flower, a tiny spectacle of the rainforest.

Jay Falk, a National Science Foundation postdoctoral fellow at the University of Colorado, Boulder, and the Smithsonian Tropical Research Institute (STRI) in Panama, expected to find something like that when he sought this species out in Panama. What he didn’t expect was a caterpillar in the nest of one of these birds. At least it looked like a caterpillar—it was actually a hatchling with some highly unusual camouflage.

The chick was covered in long, fine feathers similar to the urticating hairs that some caterpillars are covered in. These often toxic barbed hairs deter predators, who can suffer anything from inflammation to nausea and even death if they attack. Falk realized he was witnessing mimicry only seen in one other bird species and never before in hummingbirds. It seemed that the nestlings of this species had evolved a defense: convincing predators they were poisonous.

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© Jeff R Clow

We probably inherited our joints from… a fish

What do we have in common with fish, besides being vertebrates? The types of joints we (and most vertebrates) share most likely originated from the same common ancestor. But it’s not a feature that we share with all vertebrates.

Humans, other land vertebrates, and jawed fish have synovial joints. The lubricated cavity within these joints makes them more mobile and stable because it allows for bones or cartilage to slide against each other without friction, which facilitates movement.

The origin of these joints was uncertain. Now, biologist Neelima Sharma of the University of Chicago and her colleagues have taken a look at which fish form this type of joint. Synovial joints are known to be present in jawed but not jawless fish. This left the question of whether they are just a feature of bony skeletons in general or if they are also found in fish with cartilaginous skeletons, such as sharks and skates (there are no land animals with cartilaginous skeletons).

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Even the worst mass extinction had its oases

About 252 million years ago, volcanic eruptions triggered the End-Permian Mass Extinction, also known as the Great Dying. About 96 percent of marine species were wiped out—but were things just as grim on land?

Scientists have debated whether this event caused nearly as much terrestrial destruction. Now, researchers from the Nanjing Institute of Geology and Paleontology (NIGPAS) of the Chinese Academy of Sciences suggest that terrestrial ecosystems did not suffer nearly as much as the oceans.

Led by paleontologist Feng Liu, the NIGPAS team found evidence for refugiums, oases where life thrived despite the devastation. Not only did these refugiums give life a chance to survive the mass extinction event, which lasted 200,000 years, but they are now thought to have been crucial to rebuilding ecosystems in much less time than was previously assumed.

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© Corey Ford

Flashy exotic birds can actually glow in the dark

Found in the forests of Papua New Guinea, Indonesia, and Eastern Australia, birds of paradise are famous for flashy feathers and unusually shaped ornaments, which set the standard for haute couture among birds. Many use these feathers for flamboyant mating displays in which they shape-shift into otherworldly forms.

As if this didn’t attract enough attention, we’ve now learned that they also glow in the dark.

Biofluorescent organisms are everywhere, from mushrooms to fish to reptiles and amphibians, but few birds have been identified as having glowing feathers. This is why biologist Rene Martin of the University of Nebraska-Lincoln wanted to investigate. She and her team studied a treasure trove of specimens at the American Museum of Natural History, which have been collected since the 1800s, and found that 37 of the 45 known species of birds of paradise have feathers that fluoresce.

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© TeeJe

The seemingly indestructible fists of the mantis shrimp can take a punch

The mantis shrimp comes equipped with its own weapons. It has claws that look like permanently clenched fists that are known as dactyl clubs. But when it smashes the shells of its prey, these fists come out of it undamaged.

When throwing punches, mantis shrimp can strike at the speed of a .22 caliber bullet (about 1,316 kmph or 818 mph)—one of the fastest movements in the animal kingdom. That generates a force over a thousand times their body weight. However, unleashing that much energy can backfire because the shockwaves it produces could seriously damage an animal’s soft tissue. None of that seems to affect the mantis shrimp. Now we finally know why.

When a team of researchers from Northwestern University studied the dactyl clubs of one mantis shrimp species, they found that they have layered structures that selectively block sound waves, acting as protective gear against vibrations that could otherwise harm the shrimp. These types of structures, known as phononic mechanisms, filter out sound waves that could otherwise cause nerve and soft tissue trauma.

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© Giordano Cipriani

Parrots struggle when told to do something other than mimic their peers

There have been many studies on the capability of non-human animals to mimic transitive actions—actions that have a purpose. Hardly any studies have shown that animals are also capable of intransitive actions. Even though intransitive actions have no particular purpose, imitating these non-conscious movements is still thought to help with socialization and strengthen bonds for both animals and humans.

Zoologist Esha Haldar and colleagues from the Comparative Cognition Research group worked with blue-throated macaws, which are critically endangered, at the Loro Parque Fundación in Tenerife. They trained the macaws to perform two intransitive actions, then set up a conflict: Two neighboring macaws were asked to do different actions.

What Haldar and her team found was that individual birds were more likely to perform the same intransitive action as a bird next to them, no matter what they’d been asked to do. This could mean that macaws possess mirror neurons, the same neurons that, in humans, fire when we are watching intransitive movements and cause us to imitate them (at least if these neurons function the way some think they do).

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© Jim Cumming

Life is thriving in the subsurface depths of Earth

From the flamboyant blossoms and birds of rainforests to the living rainbows of coral reefs, Earth’s surface is teeming with life. But some of its most diverse and fascinating biomes are thriving in the darkness below.

We used to think that the subsurface was a far-from-ideal place for living things. Habitats that can soak up light and warmth from the Sun have the energy to sustain many forms of life and so were viewed as the most diverse. That view is now changing.

Led by Emil Ruff of the Marine Biological Laboratory (MBL), Woods Hole, Mass., new research has unearthed communities of underground microbes that are almost as—and sometimes more—diverse than even reefs and rainforests. Ruff and his team found that subsurface bacteria and archaea are flourishing, even at depths where the energy supply is orders of magnitude lower than enjoyed by organisms in habitats that see the sun.

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© HAYKIRDI

Manta rays inspire faster swimming robots and better water filters

Manta rays are elegantly shaped. They swim by flapping their fins like enormous wings, and their gills filter for plankton with the utmost precision. These creatures have now inspired human innovations that take soft robots and water filters to the next level.

With fins that borrow their shape and motion from mantas, a soft robot created by a team of researchers at North Carolina State University and the University of Virginia improves on a previous model by reaching speeds of 6.8 body lengths per second, nearly double what its predecessor was capable of. This makes it the fastest soft robot so far. It is also more energy-efficient than its previous iteration and can swim not just on the surface, but upward and downward, just like an actual manta ray.

Another research team at MIT used the gills of these creatures, which filter for plankton, to improve commercial water filtration systems. Their gill openings are also the perfect size to help them breathe while they feed, absorbing oxygen from water on its way out. The rays’ balance of feeding and breathing helped the researchers figure out a filter structure that more precisely controls inflow and outflow.

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© MLADEN ANTONOV/AFP via Getty Images

Frogfish reveals how it evolved the “fishing rod” on its head

Behold the frogfish. This bizarre creature really is a fish, despite its bullfrog face, pectoral fins that look like webbed feet, and a froglike mouth that snaps up unsuspecting prey.

But the way it lures its prey is even weirder. Frogfish belong to the anglerfish family known as Antennariidae. Like their anglerfish cousins who lurk in the ocean’s depths, these ambush predators attract their next meal via an appendage on their heads that they use like a fishing lure. This appendage is known as the illicium and thought to have once been a dorsal fin. It has a specialized skin flap, the esca at the end. It tantalizes small fish and crustaceans into thinking it’s a worm until they come too close.

How frogfish controlled the illicium was previously unknown. Led by biologist Naoyuki Yamamoto of Nagoya University, a team of researchers have now discovered that a specialized population of motor neurons have evolved to allow it to shake the illicium around like a wriggling worm. Yamamoto thinks they were originally dorsal fin motor neurons that became more specialized.

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© Divelvanov via Getty

When does your brain think something is worth the wait?

Whether it’s braving the long line at a trendy new restaurant or hanging on just a few minutes longer to see if there’s a post-credits scene after a movie, the decision to persevere or ditch it depends on specific regions of our brains.

Waiting is not always about self-control. Deciding to wait (or not to wait) also involves gauging the value of the potential reward. In an experiment that investigated wait times among people with lesions in the frontal cortex of the brain, University of Pennsylvania psychologist Joe Kable and his research team found that subjects with damage to certain regions of the prefrontal cortex were less likely to wait things out.

“[Our] findings suggest that regions of the frontal cortex make computationally distinct contributions to adaptive persistence,” he and his team said in a study recently published in the Journal of Neuroscience.

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Craving carbs? Blame an ancient gene.

There is now a genetic excuse not to bother cutting carbs. Humans have genetically adapted to eating starchy foods, and our ancestors may have been carb-ivores even before modern Homo sapiens emerged.

The salivary amylase gene, known as AMY1, is already known to have helped us adapt to eating carbs. It encodes amylase, an enzyme that breaks starches found in pasta and bread down to glucose—and may have given us a taste preference for them. Humans have multiple copies of the gene, which may help us produce high levels of the enzyme.

Researchers from the University of Buffalo and the Jackson Laboratory have now found that, while most copies of this gene arose with the advent of farming, modern humans and our closest relatives had accumulated extra copies long before agriculture.

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© Yana Iskayeva/Getty

Lizards and snakes are 35 million years older than we thought

Lizards are ancient creatures. They were around before the dinosaurs and persisted long after dinosaurs went extinct. We’ve now found they are 35 million years older than we thought they were.

Cryptovaranoides microlanius was a tiny lizard that skittered around what is now southern England during the late Triassic, around 205 million years ago. It likely snapped up insects in its razor teeth (its name means “hidden lizard, small butcher”). But it wasn’t always considered a lizard. Previously, a group of researchers who studied the first fossil of the creature, or holotype, concluded that it was an archosaur, part of a group that includes the extinct dinosaurs and pterosaurs along with extant crocodilians and birds.

Now, another research team from the University of Bristol has analyzed that fossil and determined that Cryptovaranoides is not an archosaur but a lepidosaur, part of a larger order of reptiles that includes squamates, the reptile group that encompasses modern snakes and lizards. It is now also the oldest known squamate.

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© Lavinia Gandolfi/David Whiteside, Sophie Chambi-Trowell, Mike Benton and the Natural History Museum, London

Researchers finally identify the ocean’s “mystery mollusk”

Some of the most bizarre lifeforms on Earth lurk in the deeper realms of the ocean. There was so little known about one of these creatures that it took 20 years just to figure out what exactly it was. Things only got weirder from there.

The organism’s distinctive, glowing presence was observed by multiple deep-sea missions between 2000 to 2021 but was simply referred to as “mystery mollusk.” A team of Monterey Bay Aquarium Research Institute (MBARI) researchers has now reviewed extensive footage of past mystery mollusk sightings and used MBARI’s remotely operated vehicles (ROVs) to observe it and collect samples. They’ve given it a name and have finally confirmed that it is a nudibranch—the first and only nudibranch known to live at such depths.

Bathydevius caudactylus, as this nudibranch is now called, lives 1,000–4,000 meters (3,300–13,100 feet) deep in the ocean’s bathypelagic or midnight zone. It moves like a jellyfish, eats like a Venus flytrap, and is bioluminescent, and its genes are distinct enough for it to be classified as the first member of a new phylogenetic family.

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© MBARI

Supermassive black hole binary emits unexpected flares

What happens when a gargantuan cloud of gas swallows a pair of monster black holes with their own appetites? Feasting on the gas can cause some weird (heavenly) bodily functions.

AT 2021hdr is a binary supermassive black hole (BSMBH) system in the center of a galaxy 1 billion light-years away, in the Cygnus constellation. In 2021, researchers observing it using NASA’s Zwicky Transient Facility saw strange outbursts that were flagged by the ALerCE (Automatic Learning for the Rapid Classification of Events) team.

This active galactic nucleus (AGN) flared so brightly that AT 2021hdr was almost mistaken for a supernova. Repeating flares soon ruled that out. When the researchers questioned whether they might be looking at a tidal disruption event—a star being torn to shreds by the black holes—something was still not making sense. They then compared observations they made in 2022 using NASA’s Neil Gehrels Swift Observatory to simulations of something else they suspected: a tidal disruption of a gas cloud by binary supermassive black holes. It seemed they had found the most likely answer.

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© Northwestern University

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