The feathered Archaeopteryx long ago laid claim to the title of oldest known bird—but it appears there's a new oldest winged critter in town. Scientists have found a fossil of a feathered dinosaur that predates Archaeopteryx by some 10 million years: Aurornis xui, discovered in northeastern China. The find, thought to be some 160 million years old, "pushes (back) the origins of birds—or origin of animals that are very closely related to the bird," says a paleontologist. But plenty of questions remain, the Los Angeles Times notes.
While the authors of the study in question say Aurornis xui is the earliest known bird, other experts aren't certain it qualifies as a bird at all. "Around the origin of birds 160 million or so years ago, there were many fossils that were experimenting with birdness—getting more and more bird-like," says the paleontologist, who wasn't involved in the study. "What exactly the line is that made it to birds is not entirely clear ... and this is just one candidate." What's more, the fossil's incredible preservation casts some doubt on the extent of its authenticity, he says, adding that up to 80% China's museum fossils are believed to be "enhanced" by humans. (Read more dinosaurs stories.)