Early Birds

The oldest known ancestor for modern birds was recently discovered in China and was announced yesterday.

Paleontologists have unearthed the exquisitely preserved fossils ofwhat is the oldest known ancestor of modern birds, a loonlike swimmerand flier that flourished in lake country 110 million years ago in whatis today northwest China.

The fossils included five headless butotherwise nearly complete skeletons that show the outlines of softtissues, including feathers and ducklike webbing between the toes.Researchers said the find suggested modern birds may have evolved fromaquatic ancestors.

An international team led by Hai-lu You, of the Chinese Academy of Geological Sciences, found the fossils, known as Gansus yumenensis, in Gansu province near Changma, a mountain community about 1,200miles west of Beijing. Results of their research are reported today inthe journal Science.

"They were clearly able to fly but were alsoadaptable for swimming and diving," said team member Matthew C.Lamanna, of the Carnegie Museum of Natural History. "We don't know what they ate because we don't have a skull, but the legs and feet are thoseof a diver. He had a powerful kick stroke."

Gansus is being compared in appearance and behavior to modern loons, grebes, and diving ducks, but was actually fairly small. The Post article says it was close to magpies in size; perhaps a murrelet or auklet would be a closer analogy for something that small that spends most of its time on the water. The modern diving birds spend almost their entire lives on the water, some of them coming ashore only to breed.

Grrlscientist has more on the implications of the discovery, and how this fossil fits into the avian lineage. One of the interesting implications is that modern birds evolved from primarily aquatic species after most terrestrial species had become extinct. This is just something that will need to be worked out later.

technorati tags:Gansus yumenensis, Birds, Evolution, Fossils