Re: Parasites and paleoanthropology

Glenn A. Friedrich (glenn@lexgen.com)
Wed, 17 Jul 1996 09:04:55 -0500

In article <837563874snz@crowleyp.demon.co.uk>, Paul@crowleyp.demon.co.uk wrote:

[...]

: Nearly all h.s.s. parasites and intermediates are associated with
: bodies of fresh water.

Do you have documented data that "most" of the 200 species (your number)
of human parasites are "associated" (what does that mean?) with bodies of
fresh water? Can you provide references? Put some meat on your argument
and provide real numbers and use more exact terminology. Is it 85% of
species or over 90%? Turn your speculation into something a bit more
substantial.

: In each case the h.s.s. population must
: have achieved a minimum density in the area to justify speciation.

Why? Can you quantitate what you mean by 'minimal'? What percent of any
given parasite's life cycle is spent in a human host? Why can't your
strawman savannah theory call for some existence of humans near bodies of
water? Heck, I can assume with fair confidence that our ancestors had to
drink water. And why wouldn't this exposure to water be more than adequate
to allow parasites to flourish? Malaria is alive and well without tribes
of aquatic apes roaming the modern day wetlands.

As an aside, your use of the word 'justify' in the above quoted passage is
unfortunate. Speciation requires no justification because it doesn't see
into the future. Which particular speciation events happen to occur is a
matter of chance.

[...]

: I suggest that a thorough and wide-ranging study of h.s.s.
: parasites (and their evolution) would show that fairly dense,
: localised and sizeable hominid populations have inhabited areas
: close to standing bodies of fresh water in the tropics at or near
: sea-level for many hundreds of thousands of years. In other words,
: such a study would go to disprove hunting/savannah theories of
: human evolution.

I suggest you might want to flesh out your hypothesis with a little
preliminary data before anyone embarks on a 'thorough and wide-ranging
study' as you suggest. Such data isn't difficult to come by. But of course
a fundamental question which you may find a considerable hurdle is
defining your minimal host population required for parasite speciation.
Good luck.

--Glenn A. Friedrich