Re: What are race promoters promoting?

gkeyes6988@aol.com
26 Nov 1996 23:57:57 GMT

Susan accidentally sent me this as e-mail, realized her mistake, and asked
me to post it. The unmarked passages are thus hers. -- Greg Keyes

In article <19961125145700.JAA16642@ladder01.news.aol.com> you wrote:

: (Susan 1)
: Susan S. Chin wrote:
: : >My understanding is that races are geographical variants of a
species.
: : >The morphological differences between populations become greater the
: : >farther apart these populations are.

: (Greg 2)
: Phenotypic variation is based upon present environment, not past
: environment.

What exactly do you mean by this?

: What you mean is that past environments caused a change in gene
frequency
: (higher frequency of short stature in the Ituri) or, in other words, a
: change
: in genotype. If the Ituri and the Bantu had similar genotypes, they
would
: have similar phenotypes because they share a similar developmental
: environment.

What I meant is that adaptations to past environments selected for
certain traits which are advantageous in a given environment. These
traits come about as a result of the interaction between the genotype and
the environment, otherwise known as the phenotype.

: Assuming that your argument that these three groups originated in
: different local environments that shaped the frequencies of genes in
their
: respective
: populations disparately is true, then in what sense are they all
"Negroid"
: ( you say, remember, that there are three basic types, and I assume that
: this is the one all three of these fall into)?

On the basis of geographic origins. All 3 groups are African. I'm not
making any statements about their genotypic similiarities, since it's
well known that there is a much higher degree of genetic variation in
African populations than is found elsewhere in the world.

For those who prefer to view race as a social category, why not add
geography to it? No one can deny one's evolutionary history, family
lineage, if discernable?

: Once again, I agree that there is variation from one human population to
: the next -- it just isn't a bounded variation.

I don't believe "bounded variation" was ever mentioned, or implied in any
of my posts. Just because races exist (IMO), they have to be
discontinuous?

: (Susan 1)
: : >The similarities between populations
: : >are due to similar adaptations to environmental demands.

: (Greg 1)
: : Since humans use culture to do the bulk of their adapting, actual
: : adaptational differences are few (like the sickle cell trait). Most
: other
: : so-called adaptations to climate are the result of phenotypic
plasticity
: : or non-adaptive factors like gene drift and the founder affect.

If you're familiar with Bergman's Rule and Allen's Rule, I don't see how
adaptations to the environment (which encompasses more than just climate)
can be viewed as a chance factor.

: (Susan 2)
: *If humans used culture to do the bulk of their adapting, at
: *what point did this begin? When we became anatomically modern Homo
: *sapiens, we stopped evolving biologically? Obviously the human lineage
: *has evolved biologically through time, why would you expect this to
stop
: *at Homo sapiens? Or at the level of "races"?

: (Greg 2)
: Note first that I did not say biological adaptation was absent -- on the
: contrary, I even gave an example of it (the sickle cell trait is an
: adaptation to malaria). What I said is that most adaptations are made
: culturally. Amazon basin groups did not adapt physically to eat the
: poisonous Manioc root, they developed a technology (cooking) to
: make the root edible to their already existing systems.

Those same Amazon basin groups had already evolved in their skin color,
body type, hair type to this environment long before the technology came
along. (assuming this is their original long term habitat)

: Melanesians and Australian aborigines also have dark skin
: and you are probably right, this is due to a history in the tropics --
but
: that doesn't make them evolutionarily very close to either Bantus or
: pygmies.
: The race concept implies similar characteristics are based on close
: genetic affiliation.

A geographic concept doesn't necessarily imply evolutionary closeness.

: Other 'adaptations' -- such as larger lung cavities in high altitude
: populations -- are developmental -- a result of phenotypic plasticity,
not
: of a change in gene frequency (evolutionary adaptation).

This is how I would distinguish genotype vs phenotype. Take two
individuals up to a high altitude, have them train at that altitude for 5
years. At the end of this period, will they both perform at the same
level due to environmental adaptations with larger lung capacity?
Phenotype is plastic to a certain extent, but it is constrained also by
the underlying genotype.

: (Susan 1)
: : >This racial differentiation occurred once early hominids spread
beyond
: : >Africa and the Old World.

: (Greg 1)
: : This is certainly one view of human origins -- that Homo erectus
evolved
: : separately into H. sapiens in different places...

: (Susan 2)
: *I made a very general statement in saying "early hominids spread beyond

: *Africa and the Old World." Are you disputing the idea that the human
: *lineage began in Africa, and spread from there? Early hominids does not

: *imply Homo sapiens!

I should have added Homo erectus, since some now feel Homo habilis
could have been the first to leave Africa, and not erectus.

: (Susan 1)
: : > Limited interbreeding between populations lead to these
: : >phenotypic differences which we can easily recognize as a "racial
: type,"
: *... The definition of phenotype used here is "the
: *observable expression of the genotype." Phenotypes are *based* on
: *genotypes, how else would these observable characteristics come about?

: (Greg 2)
: Yes, but phenotypic adaptations are not heritable. A Norwegian can tan
: all he or she wants, but their child will not be born tan.

No, but an obvious phenotypic characteristic of a Norwegian is his/her
very light skin color, a phenotypic adaptation to their (or ancestors')
northerly environment. Phenotypic adaptation also implies underlying
genotypic changes in my usage.

In what circumstance would it be adaptive for a light skin colored person
to tan? Biologically adaptive, that is. (We're not talking Bain de
Soleil!!)

We're not using phenotype in the same way.

: Only if there is a
: change in gene frequency (genotype) will that happen. In suggesting
that
: people evolve to meet the needs of particular environments -- and then
: carry
: these traits with them to new environments (i.e the pygmies being in
some
: environment that selected for shortness -- whatever environment that
would
: be
: -- and then carrying it with them to their present homeland where they
are
: surrounded by much taller groups) you suggest a change in genotype, not
: phenotype. And of course, genotypes do vary from group to group, but
not
: in
: a simplistic "racial" way -- unless you want to admit to hundreds or
even
: thousands of "races" which still grade into one another.

There is an interaction going on between the phenotype, the environment,
selection for certain traits thru time (no Lamarckians here), and of
course a change in the gene frequency of the population which favors
certain phenotypes. None of this happens overnight obviously.

At no time did I involve the genotype in my races by geography idea. You
seemed to think I meant genotype, when in fact, I've only talked about
phenotypes, the observable characteristics of the organism.

: (Greg 1)
: : Another view (from the one you propose above) is that there has been
: : considerable gene flow throughout human history, and that humanity
: : represents a continuum of physical variation which we arbitrarily
divide
: : into artificially discreet races.
<bunch of stuff snipped>

It probably doesn't matter how you or I view races then. What's there is
there. We can choose to view them as we see them. What you see as a
continuum of human physical variation arbitrarily divided, I see as a
continuum of human variation with discernible patterns due to the
evolutionary history of the populations. The fact that we're not able to
quantify or characterize races or reach a consensus doesn't make them any
less real or any more artificial.

: Human variation exists. Racial typologies are messy because they are
: artificial. They conceal the real sources and extent of variation.

When did racial typologies come into this? What are these real sources of
variation?

: (Greg 2)
: These came right off of my shelves, and thus may not be as "current" as
: you
: would like. If you want even more current ones, I can get them easily
: enough. I'm surprised, actually, that you even ask for this. If you
: want
: more sources, I'll get them, but please don't accuse me of using older
: sources because newer ones don't back me up: that would be a pain for me
: and
: ultimately embarrassing for you.

By asking for a current citation, I've accused you of using older
sources? That never occurred to me, actually.

Thanks for the sources though.

: For the sake of clarity, I'll repeat: the consensus of physical
: anthropologists today -- whether you agree with them or not -- is that
: race typologies are neither demonstrable nor useful as research tools.

Using geographic origins to characterize the patterns in human variation
is not my definition of racial typologies.

: (speaking of the history of 'racial' typology)
: "The fact is, generalized references to human types such as "Asiatic" or
: "Mongoloid" "European" or "Caucasoid," and "African" or "Negroid" were
at
: best mere statistical abstractions about populations in which certain
: physical features appeared in higher frequencies than in other
: populations; no example of "pure" racial types could be found.

The concept of "pure" racial types never came up either. Characterizing
races by geography doesn't imply that the racial groups are "pure" by any
means.

: "Human racial classification is of no social value and is positively
: destructive of social and human relations. Since such racial
: classification
: is now seen to be of virtually no genetic or taxonomic significance
: either,
: no justification can be offered for its continuance (R. Lewontin in
: EVOLUTIONARY BIOLOGY 1972, volume 6 pg 397)"

This is unfortunate. I personally feel studying human "racial" variations
could lead to understandings of human adaptations and the source of this
variation. By denying that there is a pattern to it, implies that this
variation is somewhat meaningless.

: (Susan 1)
: : >Recognizing that races exist as a phenotypic category,

: (Greg 1)
: : Again, you certainly mean genotypic here.

: (Susan 2)
: *No, I meant phenotype.

: (Greg 2)

: If you mean heritable characteristics which distinguish distinct "races"
: you mean genotype. Sure, you can't see a genotype, only a phenotype,
but if
: you aren't arguing that "races" have distinct heritable characteristics,
I
: can't imagine what you are arguing. Why haven't the people of East
Indian
: descent born in
: Singapore developed epicanthic folds -- or those of Chinese descent lost
: theirs? They both live in the same environment now. It's because their
: expressed phenotypes derive from differing genotypes.

But that expressed phenotype evolved through time, which explains why
East Indians born in Singapore wouldn't "develop" an extra fold in the
eyelid (which is thought to protect the eyes from harsh weather, but who
knows?) As for why Chinese living in Singapore haven't lost theirs,
what adaptive value would come from such a change?

: (Greg 2)
: Well, this is the unsystematic way we got stuck with racial typologies
in
: the first place. People in Africa all "look" more like each other than
: they "look" like Europeans. This "common sense" notion has failed under

close
: scrutiny, as do many "common sense" notions. Sure the world LOOKS flat
.

Which sort of brings up the inevitable question, which is more important
in assessing whether race exists as a biological reality, the phenotype
or the genotype? And why.
***phenotype = underlying genes expressed in a given environment
adaptively

: there must be something about your "phenotype" argument I'm not
: grasping. Are you claiming that there is no real genetic variation --
or
: that phenotype is the proper criterion for recognizing races? If the
: latter:
: 1. With DNA analysis available now, I see no reason to use phenotypic
: variation as a way of understanding evolutionary relationships. Studies
: of
: plasticity, yes, but even those studies are inevitably enhanced by a
: better
: understanding of the genetic envelope within which phenotypic variation
: occurs.
: 2. If a "genetic" basis of race has been a problem how much more so the
: plastic phenotype, which is peculiar to individual history and
influenced
: by
: such factors as nutrition, disease, altitude, and a host of other
factors.

Your phenotype is alot more plastic than mine. Height, body type, skin
color, hair type, those are phenotypic characters shaped by environment
through evolutionary time. The other factors are purely cultural factors
(nutrition, disease, etc.), those are certainly plastic. I have no
problem with that.

: (Susan 2)
: Glad we found something to agree on :)

: (Greg 2)
: Me too. It's nice to debate with someone on this ng who has some sense
: and
: can frame a cogent argument. Check out a few other threads and see what
I
: mean.

Yes. And please, don't take anything I've said personally. Because it is
definitely not. ("You're not wrong. But your ideas...well :)

Susan