![]() ![]() Feathers provided the evolutionary advantages-warmth, display, and for some, flight-that allowed these dinosaurs to outcompete their unfeathered peers and reptiles. What drove that miniaturization? Feathers. In a commentary accompanying that report, Michael Benton of the United Kingdom's University of Bristol wrote that miniaturization is "what makes a bird a bird and not a flying dinosaur." (For more on what happened later, see: "Birds Evolved Slowly From Dinosaurs-Then Took Off.") That rate of change in body size happened much more quickly in this line of dinosaurs than in others. In August, for example, a team headed by paleontologist Michael Lee of the South Australian Museum in Adelaide reported in Science magazine that the dinosaur ancestors of birds decreased in weight from about 359 pounds (163 kilograms) to 1.8 pounds (0.8 kilograms) over 50 million years to reach the size of Archaeopteryx. Recent surveys of fossil sizes show that the ancestors of birds shrank rapidly over the tens of million of years before Archaeopteryx appeared. (Enjoy a fun look at the diversity of modern feathers.)įeathers supercharged dinosaur evolution. Vinther now thinks that dinosaur skins likely sported all sorts of complex bristles and feathers, "all the way back to the common ancestor of dinosaurs." Perhaps this even includes the flying reptiles that lived as far back as 228 million years ago called pterosaurs, "which also have fluffy skin."Īltogether, the recent finds not only point to the startling antiquity of feathered critters, says paleontologist Martin Sander of Germany's University of Bonn, but they also help explain their evolutionary emergence. "We can now be very confident that feathers weren't just an invention of birds and their closest relatives but evolved much deeper in dinosaur history," says Steve Brusatte of Scotland's University of Edinburgh. Its discoverers had suggested the filaments along its back resembled feathers, and at the time, the idea met with some controversy. That find also adds support to the 2009 discovery of the bristled Tianyulong, a running dinosaur unrelated to bird ancestors that also lived in China around the same time. That a feathered Kulindadromeus belonged to a group unrelated to birds demonstrates that "of course, evolution is not directed to a final outcome that we see as a bird," says Vinther. Unlike most previous feathered finds, it belonged to a different group than the theropod dinosaurs, kin to Tyrannosaurus rex and modern-day birds. A running dinosaur, Kulindadromeus, lived in Siberia about 160 million years ago, covered in thin, downy, ribboned tufts of feathers. Those feathers also suggest that Archaeopteryx wasn't much of a flyer. A gorgeously preserved Archaeopteryx was unveiled in July, sporting feathers from its head to its feet, rather than just on its wings and tail as had long been thought. Unrelated to modern-day birds, the find points to a wide diversity in feathered features in dinosaurs. A "two-tailed" feathered dinosaur called Jeholornis flaunted a jutting frond of feathers on a trailing fan some 120 million years ago. Now, more dinosaur discoveries reveal how deep the roots of feathered dinosaurs really go: The revisions began in the 1990s when a trove of feathered dinosaurs, fleet-footed runners with surprising variety, emerged from fossil beds in China and confirmed those suspicions. (Related: "Jurassic World Stuck in the 1980s, Experts Grumble.") ![]() Instead, these fossils paint a plumage-packed picture of the age of dinosaurs. (See "Evolution of Feathers" in National Geographic magazine.)Ī series of revolutionary discoveries backs Vinther's idea and vanquishes the Jurassic Park vision of dinosaurs as leathery brutes. "I think that the common ancestor of dinosaurs probably had feathers and that all dinosaurs had some type of feather, just like all mammals have some type of hair," says paleontologist Jakob Vinther of the United Kingdom's University of Bristol. ![]()
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