A newly described, profusely feathered dinosaur may give lift to scientists' understanding of bird and flight evolution, researchers report. The creature, which stood about 28 centimeters tall at the hip, is the oldest known to have sported feathers and is estimated to be between 1 million and 11 million years older than Archaeopteryx, the first known bird.
Several fossils of the creature, which has been dubbed Anchiornis huxleyi, have been unearthed in northeastern China, Xing Xu reported September 25. The strata that contained those feathered fossils were laid down as sediments between 151 million and 161 million years ago, he and his colleagues note in a paper published online September 24 in Nature.
Two types of feather adorn the dinosaur, said Xu, of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. One kind, commonly referred to as "dino-fuzz," resembles the frayed end of a piece of yarn. The other type, similar in overall structure to the feathers of modern-day birds, consists of small filaments that branch from a larger shaft-like filament.
The dino-fuzz decorates the creature's head and neck. About two dozen of the shafted feathers adorn each forelimb and lower leg, the researchers report. Feathers on the legs and feet appear to have overlapped each other, creating aerodynamic surfaces that would have, in essence, given Anchiornis a wing on each of its four limbs. A similar configuration has been seen in other feathered dinosaurs (SN: 1/27/07, p. 53).
With so many species having this arrangement, the four-winged configuration must have been an important phase in the evolutionary transition from dinosaurs to birds, says James M. Clark, a vertebrate paleontologist at George Washington University in Washington, D.C.
Perkins, Sid. "Feathered dino predates birds: peacock-sized creature had aerodynamic appendages." Science News 24 Oct. 2009: 8. Academic OneFile. Web. 19 Nov. 2009.
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