Re: The Aquatic Adaptation of the Human Ear
David Froehlich (eohippus@curly.cc.utexas.edu)
Sat, 7 Oct 1995 17:17:56 -0500
On 6 Oct 1995, H. M. Hubey wrote:
> David Froehlich <eohippus@moe.cc.utexas.edu> writes:
>
> >of exostosis are related to damage of the bone and surrounding tissue and
> >I would hazard a guess that your problem is due to repeated stress on the
> >eardrum caused by water pressure and that it would occur in any mammal,
> >not just hominids.
>
> So? Does this mean that mammals could have developed in an
> aquatic environment?
No!!! Mammals are evolved from fully terrestrial synapsids which wear
evolved from fully terrestrial amniotes which were evolved from largely
terrestrial tetrapods which in turn were evolved from lobe finned fish.
If anything this feature is a plesiomorphy. A retained primitive feature
and it tells us nothing!!!!!!! about mammal relationships.
>
> Maybe there were two species of ape-like creatures one of which
> hung around the water longer than the tree dwellers.
>
> HOw about an environment in which there was an ocean shore right
> next to a forest. Now we could have apes who'd have to walk
> only a little bit to make it to the ocean and escape to the
> trees when they had to. With the sea levels going up and down
> thorughout the ages, it would not have been impossible for the
> sea to come up near a forest someplace. Now is the time when
> the specialists can contribute and tell us if there was a place
> in Eastern/Southern AFrica where this could have occurred.
>
This is not AAS and in fact it tells us nothing about the development of
bipedality (which is what putatively AAS was trying to do. It is quite
possible that some animals lived in a litoral environment. Some primates
do it today. This is a perfect example of moving the target.
Furthermore, there seems to be little or no evidence from the fossil
record to support it. I cannot exclude the possibility but why should
the ape spend any tme in the ocean if there is no reason for it to do
so. Food is not an option since the seashore is one of the hardest
places to get food if you do not have a rod and reel (although I have to
admit crustaceans and shellfish are a possibility) but a largely
shellfish diet can be identified by stable isotope ratios (they have done
it for indians in North America) and nobody has ever noted such stable
isotope ratios. (This latest is still being conducted and I do not know
if there are any results from hominids, but it should be possible).
David J. Froehlich Phone: 512-471-6088
Vertebrate Paleontology Laboratory Fax: 512-471-5973
J.J. Pickle Research Campus
The University of Texas, Austin, Texas 78712
|