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Re: DISCOVER/Neanderthal/Homo Sap.
cc3265@CNSVAX.ALBANY.EDU
5 Sep 1995 00:20:06 GMT
In article <DEE20s.n3B@inter.NL.net>, ghanenbu@inter.nl.net (Gerrit Hanenburg) writes:
>hubey@pegasus.montclair.edu (H. M. Hubey) wrote:
><some parts snipped in the interest of space>
>Can we gain any confidence as to the status of a palaeontological species like
>the Neanderthal.I think we can,by comparing the differences between
>Neanderthals and modern humans with those between other "wildtype" species.We
>shouldn't compare them with the domestic dog but with a natural species
>cluster such as that of the Cape fox,red fox,fennec fox,kit fox and Artic fox
>(all full species) because we may assume that these species have been subject
>to the same proces of natural selection as Neanderthals and early modern
>humans. (even better of course is to compare them with other primate groups)
>><large snip>
>An important difference however between artificial and natural selection is
>intentionality.Natural selection has no intentions,no goal and doesn't plan
>ahead.Artificial selection in its most advanced forms is more like designing.
>The speeding up of the process may also be of great importance for it may be
>this that leads to uncoupling of morphological change and speciation (i.e.the
>establishment of reproductive isolation).It's conceivable that morphology is
>more subject to change under artificial selection while the processes that
>may lead to reproductive isolation are less so.(they may have a more random
>character. e.g.in one instance only one major event like a chromosomal
>inversion may be enough for genetic incompatibility while in another case the
>cumulation of several genetic events is required.Artificial selection may not
>have any influence on this).
Yet humans DO NOT mate randomly at all. Traditionally, though this is
changing in our day, there were great cultural taboos on mating outside of
one's ethnic group or religion. Today this is less strict
but still exists. Additional factors such as socio-economic group
and education level also play a role, as do many other variables. While some
of these factors may not have existed in pre-history, some of them
undoubtably did. The factor of conscious choice is something which may or
may not exist among non-human animals, like foxes and monkeys, but we do
know for sure that it exists in humans, and has a large effect. Humans are
domestic animals, and practice their own form of artificial selection. Archaic
humans might well have done the same (there is some data from primatologists
suggesting that some non-human primates do show some amount of favoritism in
mate selection -- dominance is not the whole story). All of this (along with
the fact that, until recently, people tended to stay and breed pretty much
where they were born, distances being vast) has led to regional variation --
but NOT speciation.
Also, the process of physiological adaptation to a given environment --
also known as adaptability -- can lead to large changes in morphology (some
of which, like the "barrell chest" of those living in the Andean highlands,
could show up in the skeletal remains) which do not translate into genetic
changes and speciation. It has long been thought (so I've read) that
Neandertals were an archaic group specialized for glacial living.
My grad textbook in Physical Anthropology (Jurmain & Nelson '94)
mentioned, as I remember, certain "transitional" looking fossils, dating
before and after the classic Neandertal period. This could be taken as
evidence for inter-breeding OR evolution at work, I suppose. (The text also
mentions, incidently, fossils which appear to be an erectus-archaic mix of
some sort, which tends to support the multi-regional theory). I myself would
love to have a look at all this.
So, while it is possible that there was more than one species of Homo
running around in those days, I do not believe that anything has been
conclusively proven at this point. I get very uncomfortable when I see
someone ridiculed for making speculations, since there really is no
"established dogma," or shouldn't be, in this field. As new finds are
unearthed (almost daily, it seemed, this past summer), opinions change.
Caroline Cooper
Dept. of Anthropology
SUNY Albany
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