Latest news with #SteveBrusatte
Yahoo
13-03-2025
- Science
- Yahoo
Early mammals were all one color, study suggests
If you were to travel more than 120 million years back in time to the Early Cretaceous or Jurassic Period, you might see dinosaurs with striped tails and ruddy crests, primitive birds with iridescent feathers, and forests dominated by giant tree-like ferns. What you'd be less likely to notice are your closest relatives. Early mammals were small, strictly nocturnal, and altogether less showy–verging on downright drab, as supported by a study published March 13 in the journal Science. The new research is the first to look back at early mammals in full color. Using advanced fossil imaging methods and a thorough examination of the pigment-producing cells present in living mammals, the team have uncovered what the fur of our long-lost kin probably looked like. Across six different specimens representing five distinct near-mammalian (mammaliaform) or mammalian groups, the researchers found striking uniformity. All of the early mammal fossils examined indicated the extinct animals had unpatterned, dark-brown coats. Though perhaps not the most immediately exciting news, the finding is notable for illustrating what science has only previously been able to guess at. These new findings have implications for our understanding of mammalian evolution and hints at a future where we can reconstruct every era of the distant past in technicolor. 'When I was growing up, all of the books on fossils said that we would never know the color of extinct species,' Steve Brusatte, a paleontologist and evolutionary biologist at the University of Edinburgh who was uninvolved in the research, tells Popular Science. 'So I'm always flabbergasted with studies like these that seem to do the impossible. This is fantastic work,' he adds. The first mammal-like animals emerged alongside dinosaurs in the Mesozoic Era, aptly known as 'the Age of Reptiles.' Based on fossilized bone and skeletal impressions, paleontologists have long theorized that these early pre-mammals (and the later true mammals) were fairly small. Most were no larger than rodents, and they were predominantly active at night to avoid predation. For decades, measures of eye sockets have been some of the only concrete evidence of that nocturnal lifestyle. Now, this glimpse at some of the first mammals' true colors adds proof. Though we mammals may not be quite as colorful as our avian counterparts, modern species still display hues from purple to orange, along with varied patterns. Fur color isn't just aesthetic. It's a multi-functional adaptation that can serve purposes as varied as thermoregulation, camouflage, mate attraction, communication, and defense. Understanding how early mammals looked helps us understand how they lived and when all the present diversity evolved, says Matthew Shawkey, co-senior study author and an evolutionary biologist at the University of Ghent in Belgium. The findings 'confirm what we [thought] about early mammals–that they were living in the shadows of dinosaurs. Not only was their size and diversity constrained by the presence of dinosaurs, but also their coloration,' Shawkey tells Popular Science. 'They're basically small, dinosaur food.' To reach that conclusion, Shawkey and his colleagues built a database of living mammals. They used spectrophotometry to quantify the color of 116 modern species, and an electron microscope to closely examine the melanosomes (melanin-production and storage sacs inside melanocyte cells) of each of those animals. The team found correlations between hair color and melanosome shape and size, and used those trends to build a predictive model. Then the scientists took the same extreme, close-up view of six very well-preserved ~165 to 120-million-year-old fossils unearthed from northeastern China. The fossils were selected because they're detailed enough to include intricate impressions of fur and individual hairs, and also represent a wide swathe of early mammals and mammaliaforms. The fossils included two flying squirrel-esque gliders, a mole-like burrower, a tree-climber, and two different terrestrial creatures. One of the extinct taxa, a tiny tree-dweller with prehensile claws and wide furry membrane for sailing between branches, Arboroharamiya fuscus, is described and named for the first time in this new study. They found that the fossilized melanosomes were very similar to each other: oval shaped and mid-sized, generally lacking in the extremes present in some living mammals. Overall, the extinct species showed far less diversity than the modern ones. Using their mammalian model, the scientists predict that these melanosome measurements would have corresponded to a mousy grey-brown shade. There was some small variation between and within the specimens–'it's biology after all,' says Shawkey–but not enough to call them different colors. Likely, their universal dull, dark coloring helped these early mammals to better camouflage at night and stay warm. 'We came from such humble beginnings,' he says. Luke Weaver, a paleontologist studying mammal evolution at the University of Michigan who wasn't part of this study, is excited about the new research. 'This gives a glimpse of mammal ecology that is otherwise hidden from view,' he says. [ Related: This extinct tree-dwelling mammal may be among humans' closer relatives.] However, Weaver notes the study comes with limitations. The sample size of six fossils is small, encapsulating only a particular time period, region, and subset of all early mammals, he says– though adds that's not abnormal for paleontology. He also cautions that this dataset doesn't necessarily allow for broad inferences about mammals later on in the Cretaceous, as the fossils are mostly representative of the earlier part of the Period. The study authors suggest early mammals were stuck in a narrow ecological and evolutionary lane until the extinction of the dinosaurs. But Weaver notes that recent studies have found evidence for earlier diversification events, as much as 30 million years before the dinosaurs died out. Some early mammals displayed advanced social behaviors, as documented in his own research, and some were even dino predators–not just prey. 'There's often the tendency to think of mesozoic mammals as these kind of meager critters that were just running around hiding,' says Weaver. Though that may be true for many, particularly the earliest groups, 'I would be hesitant to draw that conclusion about all early mammals,' he adds. 'I think there's a lot of interesting things that are happening, especially in the late Cretaceous.' Additional research, examining a broader range of specimens, would be needed to assess how far-reaching the trend of brown-ish, boring mammals was, and when exactly mammals began to gain stripes, spots, patches, and brighter colors. A graduate student in Shawkey's lab has already started a project to reveal just that, in an attempt to build a detailed timeline of fur addition to illuminating our own long evolutionary journey, Weaver and others hope this and similar work underscore the value of museums and preserving fossil remains. When these fossils were initially collected, 'we didn't have the technology to interrogate these sorts of questions,' he says. 'You never know what sort of new insights you can get from old fossils.'
USA Today
04-03-2025
- Science
- USA Today
Scientists found a fossil of a Jurassic bird. Here's how it could rewrite history.
Scientists found a fossil of a Jurassic bird. Here's how it could rewrite history. Show Caption Hide Caption Massive stegosaurus fossil that sold for $44.6M goes on public display Apex, a stegosaurus fossil, was lent to the American Museum of Natural History for public display after selling for over $40 million. Scientists uncovered a 149-million-year-old bird fossil in southeastern China with unexpectedly modern traits they believe could rewrite the evolutionary history of birds. The recently discovered quail-sized creature, called Baminornis zhenghensis, flew through the skies when dinosaurs roamed the earth and is among the oldest birds ever discovered, along with the similarly aged Archaeopteryx that was found in Germany in the 1860s. The Archaeopteryx, a bird-like dinosaur that scientists describe as more reptilian-like than modern birds, were about the size of a crow. More: What lies at the center of the Earth? The answer keeps changing. Researchers from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) at the Chinese Academy of Sciences unearthed the fossil in 2023 while conducting field work in the coastal Fujian Province of China where more than 100 other fossils have been found. The study was published in the journal Nature last month. Steve Brusatte, a University of Edinburgh paleontologist, called Baminornis a 'landmark discovery' in a commentary published in Nature alongside the study. The finding, he wrote, is among the first proof that birds lived alongside dinosaurs during the Jurassic Period. The finding helps scientists answer longstanding questions about when birds began to diversify into the flying animals we think of today. More: A dinosaur museum in an unlikely place Edward Braun, a professor of biology at the University of Florida who has studied the evolution of birds, said the study's findings suggest that there was a 'much earlier diversification of birds with these modern features' than previously thought, pushing back the timeline of bird evolution. When the Archaeopteryx was discovered around 1861, it was heralded as evidence that birds were soaring in the skies by the end of the Jurassic Period. Charles Darwin said the discovery supported his theory of natural selection. But for more than a century, it remained the only bird fossil from that era. Unlike the Archaeopteryx, which featured more reptilian traits and a long tail similar to that of a velociraptor, researchers today believe the Baminornis' light-weight structure and shorter tail make it more similar to modern-day birds that easily fly by flapping their wings through the air. Until Baminornis, the only known birds with shorter tails were believed to have lived about 20 million years later. The fact that the Baminornis and Archaeopteryx lived during the same period more than 5,000 miles apart from one another and each with unique features suggests that some bird evolution had already occurred in the Jurassic Period, the study states. Discovery: Powerful 'ghost particle' with clues about the universe Braun, who was not part of the study and focuses his research on bird genome evolution, told USA TODAY discovering when species morphed helps scientists understand changes in DNA. While he said he doesn't necessarily think news of the Baminornis will change the understanding of the bird genome, he said it will contribute to our broader knowledge about the history of life. 'Understanding how the universe works, how life changed over time, gives us a lot of perspective,' Braun said. 'It gives us a framework to understand how life has changed.'
NBC News
13-02-2025
- Science
- NBC News
Chinese fossil of a Jurassic bird rewrites history of avian evolution
The fossil of a Jurassic bird unearthed in southeastern China has major implications for the history of avian evolution, researchers say. The newly discovered Baminornis zhenghensis, a quail-sized bird, roamed the skies some 150 million years ago during the Jurassic period, according to a study published Wednesday in the journal Nature, meaning it is among the oldest birds known to mankind, along with the iconic Archaeopteryx that was discovered in Germany in 1862 and is of similar age. "For more than 150 years now, Archaeopteryx has stood alone," said Steve Brusatte, a University of Edinburgh paleontologist who wrote a commentary accompanying the study. "During all of that time, it has remained as the only unquestionable bird fossil from the Jurassic Period," he told NBC News in an email. While there were other bird-like Jurassic fossils found here and there, Brusatte said there was a "huge mystery and a frustrating gap" in the fossil record: If Archaeopteryx was flying by then, other birds must have been too. So where were their fossils? The 2023 discovery of Baminornis in Zhenghe county in China's Fujian province, now among the most important discoveries since Archaeopteryx, helps fill that gap, he said, making it the "second unquestioned bird from the Jurassic Period." Unlike the half-bird, half-reptile Archaeopteryx, which had a long and skinny tail similar to that of a velociraptor, Baminornis had a short tail with some of its vertebrae fused into a short, stubby nubbin called a pygostyle — a crucial aerodynamic feature that pushes the body's center of mass toward the wings, similar to those in modern-day birds that helps them fly better. Until the discovery of Baminoris, short tails had been found only in birds known to have lived around 20 million years later, such as Eoconfuciusornis and Protopteryx. "What excites me most is that it is a more advanced bird than Archaeopteryx, and it could fly much better," Brusatte said. Baminoris was much more anatomically complex than Archaeopteryx, which Brusatte said was a "primitive" bird with claws and sharp teeth like its dinosaur ancestors. Archaeopteryx, which played a crucial role in determining that today's birds evolved from dinousaurs, was a "textbook example of a creature caught in the act of evolution like a freeze frame," he added. The vast difference between the two similarly aged birds, discovered about 5,500 miles apart, has led the team behind the Nature study to believe that avian evolution occurred millions of years earlier than previously thought, with the estimate now at about 172-164 million years ago. In addition to dozens of fossils of aquatic or semi-aquatic animals, the Zhenghe Fauna collection includes at least three avialan fossils so far. The researchers said that suggests the collection holds great potential to "enrich our understanding of early bird diversification" and "fill a critical gap in the evolutionary history of terrestrial ecosystem" toward the end of the Jurassic period. Though the Baminornis fossil preserved much of the skeleton, the feathers were not preserved, leaving unanswered questions about the size and structure of its wings. It was also missing the skull, limiting clues about the bird's diet. Nevertheless, "Baminornis tells us that a variety of birds lived during the Jurassic, and they flew in different ways," Brusatte said.
