First birds were poor fliers

Experts say feathers weren’t strong enough to flap

The earliest birds did not have strong enough feathers to take to the air by flapping their wings and were gliders at best, researchers said Thursday.

While modern birds have feathers with a strong central shaft that is hollow to reduce weight, the earliest-known bird Archaeopteryx and another ancient ancestor had feathers that were much thinner and weaker.

Robert Nudds of the University of Manchester and Gareth Dykearchaeoptery of University College Dublin calculated in a report in the Friday issue ofl Science that even if their feather shafts were solid, they would still have been barely strong enough to allow gliding.

Archaeopteryx lived in the late Jurassic period, about 140 million years ago, and Confuciusornis in the early Cretaceous, around 100 million years ago.

It is widely believed among paleontologists that the first birds arose from small, feathered dinosaurs.

One theory is that birds evolved from small dinosaurs living in trees that initially used feathers to control their descent like a parachute, then glided through the forest canopy and eventually flapped their wings to achieve true flight.

"Some thrust generation by these fossil birds cannot be discounted, but the vigorous flapping flight of modern birds is highly unlikely," the researchers concluded.

Nudds said poor flight ability suggests that the early birds lived in trees and would launch in order to glide to another tree. If they landed on the ground they could clamber back up to gain height for their next glide.

"If Archaeopteryx and Confuciusornis were arboreal dwellers, which is suggested by my data, then it also suggests that avian flight originated in the trees and not on the ground," he said.

"Fossil wings that superficially resemble those of existing birds don't necessarily indicate flapping flight ability," concluded Nudds, who added that the origin of avian flapping flight is likely to be more recent than previously thought.