Scientists have found the first direct fossil evidence that whales once had hind legs and feet and retained smaller but functional versions of them for more than 10 million years after they left the land for a life at sea.
In a discovery of potential importance in understanding this unusual evolutionary step, the first hind limbs and foot bones of a whale ever found were identified among the fossils of a 50-foot-long animal excavated by scientists from the University of Michigan and Duke University.
The discovery, made last fall 95 miles southwest of Cairo in an Egyptian desert that once was a sea, was announced yesterday and will be described in a detailed report to be published tomorrow in the journal Science.
Dr. Philip D. Gingerich, director of the Museum of Paleontology at the University of Michigan, said in a telephone interview that the fossils provided the first firm evidence that , whales, as was long assumed, walked on four legs when they were land animals, up until 50 million years ago. The inference was drawn from anatomical studies of archaic whales, which had pelvises, and modern whales, which bear some of the traces of formerly functioning legs... [1]
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