Re: Modern Neanderthals?

David Sierra (dsierra@lonestar.jpl.utsa.edu)
Mon, 14 Oct 1996 15:56:24 -0500

On Mon, 14 Oct 1996, Yousuf Khan wrote:

[stuff deleted]

> I can guarantee you that if were having this conversation in the last
> century, we'd be calling individual races as separate species. Blacks,
> whites, orientals, etc. Let's face it there are enough features different
> between these groups to justify classifying them separately: shapes of
> noses, flatness of faces, musculature, etc. Yet today in our more
> "enlightened" times we wouldn't dream of calling any of our existing
> peoples as members of separate species, because all of those differences
> are considered "minor".

Not to mention the PRIMARY reason for considering all of us one species:
LACK OF REPRODUCTIVE ISOLATION. People from different "races" CAN
effectively mate and produce offspring capable of producing offspring
with either of thier parents groups. And there of course the fact that
there is as much allelic diversity inside a given human population as
between populations.

> I can guarantee you that in the next 100 years that some anthropologists of
> that time will be sitting around discussing how racist we were for
> considering Neanderthal features as even remotely significant. Of course,
> by then they will have their own set of prejudices to overcome.

The only good basis for designating two populations different speces is
reproductive isolation, plain and simple. That being said, the only way
to determine species differentiation on extinct populations IS through
anatimical features. Since the scientists in question (and I'm not one,
so correct me if I'm wrong, some one who does this kind of work) don't
use mere facial differences, but things a bit more telling like true
anatomical bone structures, I think that it may be a valid measure.

Again though, if the differences inside a group of H.n. over a wide
range of anatomical demesions are as great as between a group of H.n. and
H.s. the species designation has good merit. Otherwise, well, the only
way to resolve the debate is to look at gentic material. The only studies
I've seen published involving this kind of investigation point to a
common group of ancestors for all human populations. Again, this doesn't
exactly say that H.n. and H.s. were incapable of interbreeding, but it
does suggest that there isn't a large reseviour of H.n. genetic material
floating around in the H.s. genome, as would be expected if significant
amounts of interbreeding had gone on, implying reproductive isolation. I
realize there are a lots of ifs, and implications inherant in the
proceeding arguements, but then the whole field of palentology is
chock-full of implications, yes?

Any comments on my reasoning?

Later,
David Sierra