Re: thermoregulation in hominids

Michael Daunt (liz.daunt@sympatico.ca)
19 Dec 1996 18:27:24 GMT

Newington Reference Library <fp96@dial.pipex.com> wrote in article
<32B6F521.5909@dial.pipex.com>...
| Thermoregulation in Hominids
|
| by Andrew Lewis
|
| Is it just me or does anyone else have a problem with the application of
| Allen€s rule to hominids? The rule states that mammals adapt to the
| temperature of their environment through variations in limb length.
| Longer limbs give the body a larger surface area from which heat can be
| dissipated more rapidly.
|
| I don€t know if this works with most mammals but when it is applied to
| hominids it does not seem to make any sense. However, the rule seems to
| be accepted by most anthropologists.

I think that part of the problem with this is time. The length of time
that most humans have been living in their current environments is unknown.
But I think it is safe to say that the maximum would be under 100,000
years outside of the African continent. This does not really leave a lot
of time for a species to make significant localized morphological
adaptations.

A second consideration is that homo sapiens sapiens transform their local
environment to suit their physical needs. Thus, fire and clothing went out
of Africa with our ancestors. This would significantly decrease any
selective pressures on the size of various parts of the body.

Michael Daunt
liz.daunt@sympatico.ca