http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/12/14/wsquir14.xmlMammals took to the skies as long ago as the first birds, perhaps even earlier, according to a study of a squirrel-like creature from inner Mongolia.
The discovery of the fossil of the "gliding beast" raises the question about why mammals never got to fly as well as birds, though they were swooping around for 70 million years longer than scientists had thought.
"I don't think we really know why mammals never got to be as good as birds," said Jin Meng, of the American Museum of Natural History, New York, who led the study published today in the journal Nature.
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