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Re: What Are the Race Deniers Denying?
Philip Deitiker (pdeitik@bcm.tmc.edu)
Thu, 31 Oct 1996 21:38:32 GMT
geroldf@sdd.hp.com (Gerold Firl) wrote:
>Laura - a few weeks ago you posted an excerpt from cavilli-sforza
>_history and geography of human genes_ which I found very interesting.
>My apologies for the tardy response, but I wonder if you could clarify
>what he is trying to say; you wrote:
>>You are assuming, rather than demonstrating, the existence of bias.
>>Cavalli-Sforza et al. do in fact explain the problems with
>>"races" as analytical units for studying human variation. On p.19
>>of the book you mention above:
"Human races are still extremely unstable entities in the
hands of modern taxonomists, who define from 3 to 60 or more
races (Garn 1971). To some extent, this latitude depends on
the personal preference of taxonomists, who may choose to be
"lumpers" or "splitters". Although there is no doubt that
there is only one human species, there are clearly no
objective reasons for stopping at any particular level of
taxonomic splitting....
As one goes down the scale of taxonomic hierarchy toward the
lower and lower partitions, the boundaries between clusters
become even less clear. The evolutionary explanation is simple.
There is great genetic variation in all populations, even in
small ones. This individual variation has accumulated over
very long periods, because most polymorphisms observed in
humans antedate the separation into continents, and perhaps
even the origin of the species less than half a million years
ago. The same polymorphisms are found in most populations,
but at different frequencies in each, because the geographic
differentiation of humans is recent, having taken perhaps
one-third or less of the time the species has been in existence.
There has therefore been too little time for the accumulation
of substantial divergence....
From a scientific point of view, the concept of race has failed
to obtain any consensus; none is likely, given the gradual
variation in existence. It may be objected that the racial
stereotypes have a consistency that allows even the layman to
to classify individuals. However, the major stereotypes, all
based on skin color, hair color and form, and facial traits,
reflect superficial differences that are not confirmed by
deeper analysis with more reliable genetic traits.... By means
of painstaking multivariate analysis, we can identify "clusters"
of populations and order them in a hierarchy that we believe
represents the history of fissions in the expansion of the whole
world of anatomically modern humans. *At no level can clusters
be identified with races, since every level of clustering
would determine a different partition and there is no biological
reason to prefer a particular one." (my emphasis)
>>This strikes me as a pretty clear explanation.
>C-S seems to be saying that we can classify the species into an
>arbitrary number of races, depending on what level of clustering we
>choose to establish demarcations, and hence race is "unstable". I
>guess that's a fair statement, but it shouldn't be interpreted to mean
>that race has no basis in biology. The genetic clusters do exist, and
>they do correspond to the standard processes of adaptation and drift
>which always create geographic variation in any species.
I don't think any geneticist will argue this point, every population
is going to have variation to the extent it can't be made identical to
another population. The issue really revolves around who should, and
under what circumstances population based genetic distinctions be
made. There are some people in the medical fields who have tried to
equate intelligence with 'race' and these types of assertions are
founded on intelligence tests not genetics test. The reason I bring
this up is that I know folks who are involved in the study of genetics
of human intelligence, and the pathways which are unknown outnumber
the known pathways by magnitudes of ten. How can someone ascribe
intelligence without defining the relative weakness or strengths of
the points in the pathways which govern intelligence (not withstanding
the environmentally derived input in to intelligence). In modern age
when one ascribes intelligence to any form of inheritance pattern on
is obligated to provide the genetics (linkage at minimum for the
traits). This has been done for a whole host of disorders, but has
never been equated with tripartite genetic separation.
I think to answer the holo-race question biologically (and
definitively) one needs to look a hundreds, if not thousands of loci
before any of previously suggested biological phenomena can be
affirmed or rejected. In the end I have to ask the politically
perplexing issue of: what are the goals of those who what to involve
genetic distinction?
1. To keep the 'races' separated. You and I both know that while
isolation has occured, it is in no way mandated by either natural or
and reasonable manmade law (If it were numerous groups would be asked
to literally split themselves apart, this is a fundemental human
rights violation).
2. To govern the education, occupation, and liberties of people. I
have to ask, on what firm structure/function relationship is one going
to do this. It is true that the proportion of individuals in distinct
population best suited for certain occupations differs; however, the
issue is, if all things are to be held equal, has any real
(objectively scientific) definition of these differences been made
that might be useful. The answer is no, and the issue is whether it
might be best to allow the individual to search/decide which
occupation in life is best suited, rather than stereotyping an
individual group and creating mandates or quotas. [And, no this is
neither an argument for or against minority based quaota systems]
3. To use knowledge of population genetics as a statistical means of
assessing medical risks, defining best therapuetic solutions to solve
certain problems. The answer to this one is that from a therpueitc
point of view one can and should consider the genetics of the
indivudal for treatment.
There are examples of diseases which only appear in one population
of peoples but not others. There is the issue of donor populations for
organ transplant, etc. There are many other issues, but If all one has
to go by is a tripartite race definition, and there is some statisical
benefit to uising it then it can be used, but the quest should be for
better resolving that person inheritance better.
What I am about to say may seem quite snobbish, but, from my point
of view, the biological issues of race or how races should be
separated has no business in the non-scientific public sphere, as
you've pointed out the issues are far to complex for layman type
usage's. These do have a place in medical/scientific realm as we've
discussed in this and other threads.
Secondarily, the way that I've seen race used in the past is a
stereotypical means of separating social/cultural groups of people,
and again any concern of genetics of biology reflects very superficial
phenomena.
Since, as you mentioned, the genetic based partitioning of human
groups is likely to become more branched as more is learned and the
medicinal sciences will eventually accomidate the new structure, the
the funtionality of the tirparite race system for biomedical reasons
is quickly becoming obsolete. Since the non-biomedical usages both
reflect xenophobias and function as cultural separators, the use by
these laymen for attempted biological understanding (or
in-your-face-ignorance) is best retorted with 'as far as you should be
concerned 'race' [referring to the tripartite system], doesn't really
exist'. If that person really wants to understand why, you might
suggest for them to read as much as they can of the history of the
world, and some digested summaries of what molecular genetist have
found, and how the archeological record supports/extends these
findings. I don't think its appropriate here in this space to try to
argue the specifics of what constitutes a genetic partition,
particularly with people who think the world began 6000 YA, last
thursday. If they want to read, and are prepared to divorce themselves
from their preconceptions then give them a push in that direction, If
they read they will eventually figure it all out for themselves.
This issue of the biological significance of 'race' is frankly an
issue of separting ignorance from enlightenment. As you mentioned,
race can be used as a biological partition system; however, given its
acheic invention, and all the implicit social/cultural attachements
in its usage is neither adaptable to new structures and is completely
obsolete as an old one. Using race to describe genetics is like using
Newton's laws of thermodynaimcs to understand particle/wave
characteristics at the speed of light or Lamarkian inheritance to
describe early embryology, its simply obsolete.
Philip
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