Primitive birds used four wings for flight
Chinese researchers find avian fossils with feathered legs which, they say, the primitive animals used to supplement their wings
Some primitive birds boasted four wings, before evolution led them to ditch their hind feathers in favour of webbed or scaly feet, scientists in China say.
And even though the latest discovery documents new evidence of feathered feet in early birds, the question remains whether the plumes were actually a help or a hindrance in flight.
The Chinese scientists behind the study, published in the US journal , said the 11 newly described fossil specimens offer evidence the leg feathers were used as a part of a four-winged system for flying.
Researchers found the new trove of data by poring over fossils at China's Shandong Tianyu Museum of Nature, said lead researcher Xu Xing, a well-known dinosaur researcher.
The 11 birds come from five species and were relatively robust: larger than a crow, but smaller than a turkey, according to Xu, a professor at the Key Laboratory of Vertebrate Evolution and Human Origin with the Chinese Academy of Sciences.