Magazine article Science News

Evolution's Fast Track toward Slow Flight

Magazine article Science News

Evolution's Fast Track toward Slow Flight

Article excerpt

Moving slowly can take a toll on anything that flies. A plane traveling at low speed generates little lift and has a hard time staying in the air. Birds, however, evolved a solution to this aerodynamic impasse extremely early in their evolutionary history, according to evidence gleaned from a 115-million-year-old fossil discovered in Spain.

During slow flight, birds make use of a special structure called a bastard wing, or alula, which consists of several feathers attached to the first digit of the wing bones. By moving that digit, a bird can separate the feathers of the alula from the rest of the wing, creating a slot that helps channel air over the flight feathers. The improved airflow enhances lift and prevents the bird from stalling during takeoff and landing.

Because feathers rarely fossilize, scientists have had trouble tracing the evolution of this important flight adaptation. The Spanish discovery, however, features remarkably well preserved alula feathers in their original position, report Jose L. Sanz of the Universidad Autonoma of Madrid, Luis M. Chiappe of the American Museum of Natural History in New York, and their colleagues.

The paleontologists named the new species Eoalulavis, because this goldfinch-sized bird shows the earliest evidence of an alula. They describe the fossil in the Aug. 1 Nature.

"It's a significant find, and it helps to bridge the gap between Archaeopteryx and more modern birds," comments Lawrence M. Witmer, an evolutionary biologist at Ohio University in Athens. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.