More than 100 million years ago there were birds in what is now China with two sets of wings, a study of recently unearthed fossils has shown.
Researchers found evidence of large feathers on the legs of 11 bird specimens at a Chinese museum. The feathers suggest that early birds had four wings, leading scientists to suspect the wings played an early role in the evolution of birds, a report from the Christian Science Monitor stated, citing an article published Thursday in the journal Science.
The fossils are from the Cretaceous period and researchers say the feathers are stiff and stick straight out from the birds' legs and have enough surface area to be aerodynamic.
The findings support the hypothesis that birds evolved from dinosaurs. Fossil records show feathers covering the legs and feet first developed in dinosaurs, the CSM report stated. It is widely accepted that a dinosaur called the Microraptor used large leg feathers to in some way aide in flight, a report from The New York Times stated.
Whether the ancient birds used leg-wings to fly seems to be a matter of debate.
David Alexander, an animal flight specialist not involved in the study, reportedly told Science magazine that the leg-feathers probably had some sort of aerodynamic function, "although whether as stabilizers, steering vanes, or full-blown wings remains to be seen."
However paleontologist Kevin Padian reportedly told Science that he did not believe the leg-feathers contributed to any sort of flight and that the feathers would create flight-hindering drag.
Another speculation suggests that the leg-feathers were used for courtship and mating rituals.
More studies are needed before the true role of the leg feathers can be determined, the reports stated.