This press release is also available in Chinese.

If it flapped its wings, dove like a duck, and lived in China about 110 million years ago, it must be Gansus yumenensis, one of the oldest members of the lineage leading to modern birds. Spectacular new fossil specimens of the loon-like ancient bird, reported in the June 16, 2006, issue of the journal Science, help fill in the avian family tree and suggest that today's birds may have gotten their start in aquatic environments.

The five well-preserved fossils of Gansus described in Science include nearly complete skeletons consisting of three-dimensional, mostly uncrushed bones. Several of the specimens are so exquisitely preserved that the carbonized remains of feathers and even webbing in the foot can be seen clearly.

Details in the hind legs and feet of Gansus indicate that the bird was probably a foot-propelled diver like today's grebes, loons, and many ducks, although they may not have been as good at diving as their modern counterparts, according to Hai-lu You of the Chinese Academy of Geological Sciences and his colleagues.

Gansus belongs to a lineage of birds called the Ornithurae, which includes all modern birds (Neornithes) and their immediate fossil ancestors. Gansus is not a member of the Neornithes, but it is the oldest known ornithuran, the Science authors report. Ornithuran birds probably arose in the Early Cretaceous, sometime between 140 and 110 million y
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Contact: Natasha Pinol
npinol@aaas.org
202-326-7088
American Association for the Advancement of Science
15-Jun-2006