Duke University paleontologists say a 35-million-year-old fossil they reassembled suggests the discovery of a unique species.
By measuring hundreds of specimens of a 35-million-year-old fossil mammal called Thyrohyrax -- recovered from the fossil beds of Egypt's Fayum Province -- the researchers determined males of the now-extinct species had oversized, swollen lower jaws shaped much like a banana.
The team at the Duke Lemur Center speculate the animals may have used the balloon-like structural chamber that shaped their bizarre jaws to produce sound.
If that speculation is correct, Thyrohyrax and its fossil relatives would be the only mammals ever found to use such a skeletal structure for producing sound, although some dinosaurs are thought to have used similar sound-producing mechanisms.
The researchers published their findings in the March issue of the Journal of Vertebrate Paleontology, which was released in mid-April.
Copyright 2006 by United Press International
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