Re: Hominid Altitudinal-Latitudinal Adaptations
Paul Crowley (Paul@crowleyp.demon.co.uk)
Fri, 25 Oct 96 16:36:29 GMT
In article <01bbc1e0$ba8a9520$1e2770c2@default>
jdwaters@dircon.co.uk "John Waters" writes:
> The uvb factor raises certain doubts about
> the Red Sea Theory of Human Evolution. It will be interesting
> to hear Paul Crowley's reaction to your reply.
How does the UV-B factor raise certain doubts about the Red Sea
Theory? Hominids have been naked for a sigificant period of
time. Any theory must explain how the coped with UV-B during
that time. They found it advantageous (taking the whole lifestyle)
to have their skin exposed to the sun. They also had all the
usual problems of nakedness (just think of taking off your clothes
and living "naturally"); IOW exposure to all the elements: - sun,
cold, heat, and to parasites, thorns, poison ivy, etc., etc.
Our response should be (1) to propose the substantial advantages
that compensated for these problems; and (2) to suggest habitats
where the problems could be kept to a minimum - (a) a warm place
at night, (b) a location where the sky was normally overcast,
preferably a humid one at sea level; (c) where thorns, etc.,
were few; (d) where shade could be found during the heat of the
day. The other aspects of human anatomy should also be explained:
the heavy sweating, the subcutaneous fat (especially in females),
the sexual differences, etc. In this context UV-B is a problem
for all theories of human evolution but, I suggest, a _relatively_
minor one.
Above all, of course, an account must be given of the food that
the species consumed. Without that, the theory is pure hot air.
And this, with respect, is how I regard the postings in this
thread up to now. There is no point in discussing adaptations
to various latitudes or altitudes without explaining how the
species survived from day to day.
> . . . four different climatic conditions. These comprise a
> reduction in average annual temperature, reduced humidity,
> seasonal changes and changes in day length. As a result, four
> simultanous genetic adaptations are required.
I don't see how such adaptations are a problem _once_there_is_a_
_good_food_supply_. Peruvian Indians have "genetically" adapted
to high altitude in the last 6,000 years or so. That's an eye-
blink in evolutionary timescales.
BTW does anyone know how long have the Inuit been going?
Paul.
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