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Re: Not dinos, but interesting, in an evolutionary sense



Matt Bonnan wrote:

>I was only able to see the abstract of "The developing renal,
>reproductive, and respiratory systems of the African elephant suggest
>an aquatic ancestry."  While internal testicles and nephrostomes are
>interesting features of elephants, how the well-developed pillar-like
>limbs and other terrestrial features would have developed from aquatic
>mammals like the dugong, or how a complex probocis would develop,
>isn't clear.

The last common ancestor of the dugong and elephant lived about 60 million
years ago, so there's been plenty of time for elephants to adapt to land.
According to the author, the aquatic ancestor spent a few million years in
the water. Presumably dugongs became more aqutic while elephants became
less.
-- Jeff Hecht