Re: AAT Theory
H. M. Hubey (hubey@pegasus.montclair.edu)
23 Sep 1995 00:35:59 -0400
n8010095@cc.wwu.edu (Phillip Bigelow) writes:
>hubey@pegasus.montclair.edu (H. M. Hubey) writes:
>>The problem in determining the effect of the aquatic environment
>>on the physical shape has to take into account two factors
>>1) the time that the animal went aquatic
>>2) the time that the animal stayed in the environment
>>I don't see any reason to assume that an animal that went
>>into the water at a very late period in its development and
>>stayed there much less than some other animal has to have
>>the same shape. This much seems obvious.
> Your comment begs the question of, "then why bother to develop the aquatic
>hypothesis in the first place?".
1) the diving reflex
2) loss of body hair
3) bipedalism or a more streamlined body
> If the animal spent such a brief time (geologically-speaking) in an
>aquatic environment that no _clear_ aquatic anatomical characters developed,
>then I would find it hard to justify using comparative anatomy at all when
>determining "aquatic-ness" from Lucy-age fossils.
I don't know what you're referring to exactly. The lengthening of
the leg bones can easily be attributed to the crucible of the
selection mechanism of them hanging around the water and escaping
to deeper water to escape death.
As to "clear aquatic anatomical characters" I can't imagine
what you could mean except perhaps you are expecting fins or
flippers.
--
Regards, Mark
http://www.smns.montclair.edu/~hubey
|