Jurassic Beaver Discovered

Discussion in 'Science' started by Petrel, Feb 24, 2006.

  1. Petrel

    Petrel
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    Small beaver-like mammal found in Chinese Jurassic deposits.

    The original article was published in Science, but I won't be able to get a look at that until Monday at the earliest.

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  2. Petrel

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    Ji, Q.; Luo, Z.-X.; Yuan, C.-X.; Tabrum, A. "A Swimming Mammaliaform from the Middle Jurassic and Ecomorphological Diversification of Early Mammals." Science, 2006, 311, 1123-1127.

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    This mammaliaform animal has guard hairs, an inner coat of fur, and molars specialized for catching fish. The tail is somewhat flattened like a modern beaver's, although narrower. The upper portion of the tail is furred on the sides and scaled in the middle, although lower down the fur thins out and it is all scaley. The caudal vertebrae show a characteristic flattened, butterfly shape typical of animals adapted to swimming such as beavers and otters. There is a trace in the fossil that suggests webbing on the hind paws, and the forelegs are thickened and sprawling, probably originally for digging but now used for paddling as with the platypus. They have odd plated, overlapping ribs which were apparently common among mammaliaforms and cynodonts (a type of primitive reptile).

    I'm going to quote what they say about the ear structure because I'm not sure what it all means and don't want to get it wrong:

     
  3. Petrel

    Petrel
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    Fixed pic:
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