Re: Race - why & when

William Stoltzfus (bstoltz@pluto.njcc.com)
Fri, 24 Feb 1995 12:01:30 -0500

I'm venturing into deep academic waters here and am relying upon the
buddy system to help me out (and not push me under!) if my reasoning gets
too choppy. I'm a teacher attempting (absurdly, I know) to write a ninth
grade-oriented text for my class on ancient civilizations. The prologue
deals with human connections to the rest of the biological world (and
beyond) so I find the issues raised in this newsgroup fascinating. The
questions of race, differing classifications of australopithecines and
the genus homo, and finally phenotype-genotype distinctions, are
critically important to the general public, and present ninth graders
destined to become members of the general public, because of our apparent
tendancy to both perceive and fear differences that a molecular biologist
might dismiss.

I'm especially interested in the idea of speciation, which I find
troubling if it's embraced too literally. I get the feeling that one
man's ramidus is another woman's afarensis. Paleontologists are mostly
stuck, at present, with a phenotypical view of the world, until, I guess,
Jurassic Park-like fossilized DNA extraction becomes workable enough to
allow corroborating evidence from a genotypical perspective. It's
interesting to me that many fossil hunters have been reluctant to applaud
the relatively recent arrival of molecular dating; presumably the cause
of science is advanced if we have another technique at (your!) disposal.
On the other hand, I'd be bummed, too, if my discovery of ramidus, which
got me a place in both paleohistorical texts and on page C3 of the NYT,
proved to be "just" Lucy's disinherited brother or sister. (A poor
example, since the disparity in dated remains is huge.)

Reading Origin of Species (yes, it was about time), I was struck, in the
chapter on hybridization, by Darwin's discussion of plant species
crossings that yielded fertile offspring. He goes on to say, "...that
there are individual plants, as with certain species of Lobelia, and with
all the species of the genus Hippeastrum, which can be far more easily
fertilized by the pollen of another and distinct species, than by their
own pollen." (Penguin Classics reprint, 1985,p. 268) Darwin said earlier
that "neither sterility nor fertility affords any clear distinction
between species and varieties [of plants]..." (p. 266)

I've quoted sparingly, and quite possibly may have missed the point
entirely. Darwin did say, "I doubt whether any case of a perfectly
fertile hybrid animal can be considered as thoroughly well documented"
(p. 270), and, no doubt, the same is still true 136 years later. Yet
David Raup, in Extinction Bad Genes or Bad Luck?, jocularly writes, "A
species is a species if a competent taxonomist says it is" (W.W. Norton,
1991, p. 14). Perhaps the fertile offspring distinction holds truer in the
Kingdom Animalia, moreso than
in plants. Lynn Margulis claims bacteria intermingle so successfully
that differentiating them by species is problematic at best.

My woefully limited understanding of molecular biology leads me to
believe that different species exist in the eyes of the beholder, and, we
hope, in the eyes of an informed, open-minded beholder. (This is
literally true from the linguistic perspective. "Species" derives from
the Latin "specere", to look at.) Speaking molecularly, I gather there
is no difference in protein sequencing between humans and other related
species until the rhesus monkey: a range that spans families in the
taxonomic system. (Keeton and Gould, Biological Science, W.W. Norton,
1993, p. 525) And 99% of human and chimp DNA is the same (ibid, p.
732). Perhaps these numbers are meaningless at the molecular level;
finer gradations may be necessary.

If the general public and academicians (unlike, sad to say, the authors of
The Bell Curve), relied upon species and subspecies
classifications as merely helpful, then phenotypical distinctions
would be another convenient and temporary set of metaphors for describing
life. Unfortunately, for xenophobic reasons or other, "seeing is
believing" to many of us, and many of us freak when you look different
from me. This is the wavelength I'm on. Please correct my misunderstanding.