Researchers from the U.K.'s University of Southampton have built an anatomically accurate model of a feathered, five-winged dinosaur called the Microrapter, and placed it in a wind tunnel to study the evolution of bird flight.
"For years scientists thought microraptors could fly but weren't sure how," Southampton's Gareth Dyke said.
Scientists believe that the Microrapter, which lived from 120 to 125 million years ago, is one of the earliest-living flying dinosaurs. Southampton researchers found that they probably didn't need feathers to fly, but used their limbs to glide for long distance -- sort of like a flying squirrel.
"Significant to the evolution of flight, we show that Microraptor did not require a sophisticated, 'modern' wing morphology to undertake effective glides, as the high-lift coefficient regime is less dependent upon detail of wing morphology," Dyke said.
When the wind-tunnel Microrapter flew just as well with its feathers removed, Dyke and his team ultimately concluded that the Microraptor didn't develop feathers for aerodynamic functions.
"That's a key thing, because for many years scientists thought feathers were unique to birds as a great adaption for generating flight. But it seems almost 100 percent certain that feathers evolved for something else. We just have to figure out what for," Dyke said.
The scientists' findings were published Wednesday in the journal, Nature Communications.