How bird flight began

Washington, January 26 (ANI): A team of scientists from the University of Kansas (KU) and Northeastern University in China says that it has settled the long-standing question of how bird flight began.

The KU-China researchers push their research into the origins of bird flight and the early evolution of birds with decisive flight tests of a model of the four-winged gliding raptor, called microraptor.

"We've done the scientific work and flight tests to show that microraptor was a very successful glider," said David Burnham from KU.

"In 2003, they found one that was so well-preserved that you could count the feathers on its wings," he added.

A debate involving the KU scientists, recently documented by the PBS program "NOVA," had flared over the question of whether evidence supported the theory that animals developed flight as ground dwellers, as a majority of paleontologists had asserted.

But, Martin and Burnham argue that flight originated above, in the trees. Such animals would have been gliders.

According to the researchers, fossils of the hawk-sized microraptor shore up their theory.

"The controversy was that these animals couldn't spread their hind-wings to glide," said Burnham.

"But we've been able to articulate the bones in their hip socket to show that they could fly," he added.

The new flight model created by Martin and Burnham comes directly from a skeleton composed of casts of the original bones of a microraptor and the preserved impressions of feathers from specimens in Chinese museums.

These astonishingly preserved fossils give a detailed image of the plumage in the gliding raptor and make possible the construction of an accurate model.

The fossils also show that an essentially sprawling posture was a plausible hind-limb wing position to provide stable flight with gliding parameters better than those of modern "flying lemurs."

The competing "biplane posture" advanced by other researchers suggested that an upright stance provided for successful glides.

But, the KU-China team argues that this stance required an impossibly heavy head to maintain a proper center of gravity.

Furthermore, the presence of seven-inch-long flight feathers on the feet would prohibit any extended stay on the ground.

Thus, microraptor must have been completely arboreal. (ANI)