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The surprising evolution of the weirdest animals on Earth, according to a new study

The surprising evolution of the weirdest animals on Earth, according to a new study

CNN30-04-2025
The story of two of the strangest animals on the planet just got a little stranger, thanks to clues revealed by a lone fossil specimen that scientists now say represents a long-extinct ancestor. The new research could upend what's known of the evolution of the most primitive mammals alive today.
Found in Australia and New Guinea, the platypus and echidna are called monotremes, and they are unique for being the only mammals that lay eggs.
The amphibious platypus has a bill and webbed feet, like a duck, and a beaver-esque tail. The small creature spends much of its time hunting for food in the water. The echidna — fittingly known as the spiny anteater — lives entirely on land, is covered in pointy quills and has rear feet that face backward, kicking up dirt as the animal burrows into the ground. Neither animal has teeth, and though they both produce milk, they secrete it through their skin for babies (often called puggles) to lap at, because they lack nipples.
'There's plenty of weirdness to go around on these little things,' said Dr. Guillermo W. Rougier, a professor in the department of anatomical sciences and neurobiology at Kentucky's University of Louisville who studies early mammalian evolution.
'They are one of the defining groups of mammals,' Rougier said. 'The typical mammal from the time of dinosaurs probably shared a lot more biology with a monotreme than with a horse, a dog, a cat or ourselves.' Therefore, he said, monotremes provide a window into the origins of mammals on Earth.
A new study published Monday in the journal Proceedings of the National Academy of Sciences opens that window a little further. Research led by paleontologist Suzanne Hand, a professor emeritus at the University of New South Wales' School of Biological, Earth and Environmental Sciences in Australia, reveals the internal structure of the only known fossil specimen of the monotreme ancestor Kryoryctes cadburyi, which lived more than 100 million years ago.
The fossil, a humerus, or upper arm bone, was discovered in 1993 at Dinosaur Cove in southeastern Australia. From the outside, the specimen looked more like a bone from a land-dwelling echidna than a water-loving platypus. But when the researchers peered inside, they saw something different.
'By using advanced 3D imaging approaches, we have been able to illuminate previously unseen features of this ancient bone, and those have revealed a quite unexpected story,' said study coauthor Dr. Laura Wilson, a senior lecturer at the university's School of Biological, Earth and Environmental Sciences.
The team found that internally, the fossil had characteristics of the semiaquatic platypus: a thicker bone wall and smaller central cavity. Together, these traits make bones heavier, which is useful in aquatic animals because they reduce buoyancy, so it's easier for the creatures to dive underwater to forage for food. By contrast, echidnas, which live solely on land, have much thinner, lighter bones.
The finding supports the popular, but unproven, hypothesis that Kryoryctes is a common ancestor of both the platypus and echidna, and that at the time of the dinosaurs, it may have lived at least partially in the water.
'Our study indicates that the amphibious lifestyle of the modern platypus had its origins at least 100 million years ago,' Hand said, 'and that echidnas made a much later reversion to a fully terrestrial lifestyle.'
There are well-known examples of animals evolving from land to water — for example, it is believed that dolphins and whales evolved from land animals and share lineage with hippos. But there are few examples that show evolution from water to land. The transition requires 'substantial changes to the musculoskeletal system,' Wilson said, including new positioning of the limbs for life on land and lighter bones to make moving less energy-intensive.
A land-to-water transition could explain the echidna's bizarre backward feet, which Hand said it may have inherited from a swimming ancestor that used its hind legs as rudders.
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Platypus released in Australian national park for the first time in 50 years
'I think that they very elegantly prove the suggestion that these animals were adapted to a semiaquatic life very early on,' said Rougier, who was not involved in the study, though he did have contact with the authors during their research.
The primitive history of these unusual animals, he said, is 'truly crucial' to our understanding of how mammals (including humans) came to be.
'Monotremes are these living relics from a very long distant past. You and a platypus probably had the last common ancestor over 180 million years ago,' he said. 'There is no way to predict the biology of this last common ancestor without animals like monotremes.'
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Climate change is making fire weather worse for world's forests
Climate change is making fire weather worse for world's forests

Miami Herald

timea day ago

  • Miami Herald

Climate change is making fire weather worse for world's forests

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The researchers used imagery from the LANDSAT satellite network to determine how tree cover had changed from 2002 to 2024, and compared that with satellite detections of fire activity to see how much canopy loss was because of fire. Globally, the area of land burned by wildfires has decreased in recent decades, mostly because humans are transforming savannas and grasslands into less flammable landscapes. But the area of forests burned has gone up. Boreal forests lost more than two times the canopy area in 2023-24 compared with the period between 2002 and 2024, the study found. Tropical forests saw three times as much loss, and North American forests lost nearly four times as much canopy, mostly because of Canada's wildfires. Significant losses were in remote forests, far from human activities. That isolation suggests that fires are increasing primarily because of climate change, said Calum Cunningham, a fire geographer at the University of Tasmania who was not involved with the study. 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Years with extreme fire-weather conditions had more forest fires and more carbon dioxide emissions than typical years without severe fire weather. Carbon dioxide, the main greenhouse gas, acts as a blanket in the atmosphere, trapping the sun's heat and warming the environment. Neither study's findings were particularly surprising to the experts, because most of the regions that the studies highlighted have burned in recent years. Both studies add to a growing body of evidence that points to climate change as one of the main reasons that the planet is experiencing more frequent and more severe forest fires, often overlapping. 'It really puts to bed any debate about the role of climate change in driving these extreme fires,' Cunningham said. When more places are hit with fire weather at the same time, countries' capacities for sharing firefighting resources drop. 'You get stretched thin,' Abatzoglou said. Reduced firefighting can create a dangerous feedback loop: Bigger fires mean more emissions, which creates more fire weather and makes future fires more likely. Budget and staffing reductions at science agencies in the United States, along with policy changes, can exacerbate climate-driven changes to fire trends, said Peter Potapov, an ecologist at the World Research Institute who led the PNAS study. For instance, repealing the 'roadless rule,' which banned roads in some remote American forests, could increase human activity there, along with fire risk. Terminated satellites could degrade fire forecasting. And funding cuts to the U.S. Agency for International Development, a State Department program that has been largely dismantled by the Trump administration, ended a program that helped other countries improve their fire-monitoring capabilities. This article originally appeared in The New York Times. Copyright 2025

Expert Says AI Systems May Be Hiding Their True Capabilities to Seed Our Destruction
Expert Says AI Systems May Be Hiding Their True Capabilities to Seed Our Destruction

Yahoo

time6 days ago

  • Yahoo

Expert Says AI Systems May Be Hiding Their True Capabilities to Seed Our Destruction

We already know that AI models are developing a propensity for lying — but that tendency may go far deeper, according to one alarm-sounding computer scientist. As flagged by Gizmodo, this latest missive of AI doomerism comes from AI safety researcher Roman Yampolskiy, who made it on a somewhat surprising venue: shock jock Joe Rogan's podcast, which occasionally features legitimate experts alongside garden-variety reactionaries and quacks. During the July 3 episode of "The Joe Rogan experience," Yampolskiy, who heralds from the University of Louisville in Kentucky, proffered that many of his colleagues believe there's a double-digit chance that AI will lead to human extinction. After Rogan claimed that many of the folks who run and staff AI companies think it will be "net positive for humanity," the storied AI safety expert clapped back. "It's actually not true," Yampolskiy countered. "All of them are on the record the same: this is going to kill us. Their doom levels are insanely high. Not like mine, but still, 20 to 30 percent chance that humanity dies is a lot." "Yeah, that's pretty high," the psychedelic enthusiast responded. "But yours is like 99.9 percent." The computer scientist didn't argue, and instead offered a distillation of his AI anxiety: "we can't control superintelligence indefinitely. It's impossible." Later in the interview, Yampolskiy took another of Rogan's quips — that he would "hide [his] abilities" were he an AI — and ran with it. "We would not know," the AI doomer said. "And some people think it's already happening." Pointing out that AI systems "are smarter than they actually let us know," Yampolskiy said that these advanced models "pretend to be dumber" to make us trust them and integrate them into our lives. "It can just slowly become more useful," he said of a hypothetically brilliant AI. "It can teach us to rely on it, trust it, and over a longer period of time, we'll surrender control without ever voting on it." While the idea of an insidiously smart AI may seem like the stuff of sci-fi, Yampolskiy noted that the technology has already ingratiated itself to us in ways that could, ultimately, benefit such an AI overlord. "You become kind of attached to it," he explained. "And over time, as the systems become smarter, you become a kind of biological bottleneck... [AI] blocks you out from decision-making." As we've repeatedly seen, people are not only becoming addicted to AI, but also experiencing cognitive issues and even delusions after overusing it. It's not too hard to imagine a society full of contented AI adherents being lulled into a false sense of security by the very technology that would, per Yampolskiy's philosophy, seek to destroy us — and that's a bleak vision of the future. More on AI doom: Godfather of AI Alarmed as Advanced Systems Quickly Learning to Lie, Deceive, Blackmail and Hack

Arizona fossils reveal an ecosystem in flux early in the age of dinosaurs
Arizona fossils reveal an ecosystem in flux early in the age of dinosaurs

Yahoo

time08-07-2025

  • Yahoo

Arizona fossils reveal an ecosystem in flux early in the age of dinosaurs

By Will Dunham WASHINGTON (Reuters) -Scientists have unearthed in Arizona fossils from an assemblage of animals, including North America's oldest-known flying reptile, that reveal a time of transition when venerable lineages that were destined soon to vanish lived alongside newcomers early in the age of dinosaurs. The remains of the pterosaur, roughly the size of a small seagull, and the other creatures were discovered in Petrified Forest National Park, a place famous for producing fossils of plants and animals from the Triassic Period including huge tree trunks. The newly found fossils are 209 million years old and include at least 16 vertebrate species, seven of them previously unknown. The Triassic came on the heels of Earth's biggest mass extinction 252 million years ago, and then ended with another mass extinction 201 million years ago that wiped out many of the major competitors to the dinosaurs, which achieved unquestioned supremacy in the subsequent Jurassic period. Both calamities apparently were caused by extreme volcanism. The fossils, entombed in rock rich with volcanic ash, provide a snapshot of a thriving tropical ecosystem crisscrossed by rivers on the southern edge of a large desert. Along with the pterosaur were other new arrivals on the scene including primitive frogs, lizard-like reptiles and one of the earliest-known turtles - all of them resembling their relatives alive today. This ecosystem's largest meat-eaters and plant-eaters were part of reptile lineages that were flourishing at the time but died out relatively soon after. While the Triassic ushered in the age of dinosaurs, no dinosaurs were found in this ecosystem, illustrating how they had not yet become dominant. "Although dinosaurs are found in contemporaneous rocks from Arizona and New Mexico, they were not part of this ecosystem that we are studying," said paleontologist Ben Kligman of the Smithsonian Institution's National Museum of Natural History in Washington, who led the study published in the journal Proceedings of the National Academy of Sciences. "This is peculiar, and may have to do with dinosaurs preferring to live in other types of environments," Kligman added. This ecosystem was situated just above the equator in the middle of the bygone supercontinent called Pangaea, which later broke apart and gave rise to today's continents. Pterosaurs, cousins of the dinosaurs, were the first vertebrates to achieve powered flight, followed much later by birds and bats. Pterosaurs are thought to have appeared roughly 230 million years ago, around the same time as the earliest dinosaurs, though their oldest-known fossils date to around 215 million years ago in Europe. The newly identified pterosaur, named Eotephradactylus mcintireae, is thought to have hunted fish populating the local rivers. Its partial skeleton includes part of a tooth-studded lower jaw, some additional isolated teeth and the bones of its elongated fingers, which helped form its wing apparatus. Its wingspan was about three feet (one meter) and its skull was about four inches (10 cm) long. It had curved fangs at the front of its mouth for grabbing fish as it flew over rivers and blade-like teeth in the back of the jaw for slicing prey. The researchers said Eotephradactylus would have had a tail, as all the early pterosaurs did. Eotephradactylus means "ash-winged dawn goddess," recognizing the nature of the rock in which it was found and the position of the species near the beginning of the pterosaur lineage. Mcintireae recognizes Suzanne McIntire, the former Smithsonian fossil preparator who unearthed it. The turtle was a land-living species while the lizard-like reptile was related to New Zealand's modern-day Tuatara. Also found were fossils of some other reptiles including armored plant-eaters, a large fish-eating amphibian and various fish including freshwater sharks. The ecosystem's biggest predators were croc relatives perhaps 20 feet (six meters) long, bigger than the carnivorous dinosaurs inhabiting that part of the world at the time. On land was a four-legged meat-eating reptile from a group called rauisuchians. In the rivers dwelled a semi-aquatic carnivore from a group called phytosaurs, built much like a crocodile but with certain differences, such as nostrils at the top of the head rather than the end of the snout. Rauisuchians, phytosaurs and some other lineages represented in the fossils disappeared in the end-Triassic extinction event. Frogs and turtles are still around today, while pterosaurs dominated the skies until the asteroid impact 66 million years ago that ended the age of dinosaurs. "The site captures the transition to more modern terrestrial vertebrate communities," Kligman said.

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