DURING the Jurassic period, between about 200 million and 145 million years ago, some meat-eating dinosaurs began evolving bird-like skeletons and sprouting feathers on their bodies. One group of these creatures eventually split off to become birds, although researchers have long debated which one it was and when it actually happened. Now, a team of scientists claims to have found the earliest known bird.
About 30 species of feathered dinosaurs have been discovered in the past dozen years or so, mostly from geological formations in China's northeastern Liaoning province. But up until now, few paleontologists have argued any of them qualified as the earliest known bird. That honour has been held for 150 years by archaeopteryx, a 150-million-year-old creature discovered in Germany. Nevertheless, two years ago, China's most famous fossil hunter, Xing Xu of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, argued in a paper in Science that Archaeopteryx was not really a bird, although many researchers did not agree.
But even if Archaeopteryx is a bird, the new specimen, reported by a team led by Pascal Godefroit, a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels, could push it off its perch as the earliest one known. The new fossil, which the team has named Aurornis xui (Aurornis meaning "dawn bird," and xui in honour of Xing Xu's contributions to bird origins), was found in Liaoning province's Tiaojishan Formation, in sediments dated about 160 million years ago, according to the Nature report. Luis Chiappe, a paleontologist at the Natural History Museum of Los Angeles County in California, says it must fly through at least one important hoop before it can claim to be the first bird: Its authenticity must be proved. That's because the specimen was not found during excavations, but was supposedly found by farmers and acquired from a Chinese fossil dealer.