Re: Genetic Evolution (was: HGHG)
Lane Singer (lsd@ix.netcom.com)
30 Jan 1995 07:52:19 GMT
In <tlathropD36L2I.3sA@netcom.com> tlathrop@netcom.com (Tom Lathrop) writes:
>This post contains discussion on some points extracted from a longer
>article I posted around a week and a half ago, under the title "The
>History and Geography of Human Genes". I think I have made a rather
>strong case that recent genetic studies of the human race, in
>particular those summarized in the recent book The History and
>Geography of Human Genes, by Luca Cavalli-Sforza (and two others), do
>*not* render the common idea of "race" meaningless, despite the
>insistence of many on the Left that this is so.
It has nothing to do with "the Left" as you so ominously put it; it's
a scientific issue, pure and simple.
>Readers who agree with
>me on this should read this article carefully and use it as a resource,
>especially to counter the argument that racial differences are
>"superficial" and therefore unimportant.
Yes, of course. The color of one's skin is anything but surperficial.
Especially if you lived in South Africa several years ago and long
into the past. People such as you have made sure that the shade
of one's complexion is the determining factor in a great many
areas of life, so I can see why you would want it to be viewed
as something other than superficial.
>>[Singer]
>>>I never denied that there were flows of genetic diversity over
>>>different populations. But - our definition of "race", from a
>>>scientific perspective, bore the requirement that one population
>>>contain at least one genetic characteristic that was absent in all
>>>other populations. And this =doesn't= occur among humans, anywhere.
>
>>[Lathrop]
>>>Hold it, hold it! Exactly *where* did you get that definition of
>>>"race"? Given this definition there certainly are no distinct human
>>>races, but this definition seems pretty far from what the
>>>man-in-the-street thinks of as "race", and it seems like a pretty
>>>useless definition in any case. Given this definition, if there *were*
>>>two distinct races of humans or some other species, and even a slight
>>>amount of mixing between them occurred, then instantly there would no
>>>longer be two races! Your definition of race is far too unstable to be
>>>interesting scientifically. Of course, I can understand why it would
>>>be *very* interesting politically... :-)
>
>>The sources on this are many, but since we're talking about this
>>one book, I'll use a quote contained therein:
>>
>>HGHG, p.4
>>"For a long time anthropologists tried to reconstruct evolutionary
>>relationships and history ->on the basis of a single characteristic
>>or gene<-. A favorite ->for over 100 years<- was the cephalic index
>>(the percentage of skull breadth to length) introduced shortly before
>>the middle of the last century. However, with a single trait, two
>>populations of different origin could well turn out to be more or
>>less identical. Anthropometric traits of this kind aslo have
>>another very serious drawback: there is no guarantee that the
>>character is completely ->under the control of biological inheritance<-
>>and the the variations observed could be due to ->short term
>>response to environmental changes<-. This was shown by Boas (1940)
>>at the beginning of the centruy, ->but this lesson was, and still
>>is, usually forgotten<-."
>
>Lane, you claimed that "our definition of 'race'" required that
>populations have unique traits. When I asked you to justify this, you
>talk about the methods people were using 100 years ago to try to trace
>the origins of different populations. Non-sequitur Lane!
Slipping and sliding, Tom. The only scientifiic definitions of race
come from theories that were 100 years old, and have only now
been discredited, based upon our growing understanding of
human origins. Do you deny that our knowledge base in both
paleoanthropology and genetics has increased substantially
in just the last decade?
>*My*
>definition of race does not require such unique traits. I'd like you
>to show me a modern definition that does!
Ah, that's just it. I can't show you =any= scientific definition of race
because there isn't one to be found. I see that you refer to *your*
definition of race, but you have failed to share it with us for
some reason.
I can quote from "The History and Geography of Human Genes",
which was published just last year by Princeton University Press.
begin quote ---
1.6. Scientific Failure of the Concept of Human Races
The classification into races has proved to be a futile exercise
for reasons that were already clear to Darwin. Human races
are still extremely unstable entities in the hads of modern
taxonomists, who define from 3 to 60 or more races.
end quote ---
The entire section is filled with quotable statements
regarding this issue. Note that Cavalli-Sforza felt the
issue was important enough to warrent its own section.
He later he states that "the hope of producing a good
taxonomy is a lost cause," and "The claims of a genetic basis
for a general superiority of of one population over another
are not supported by our findings. Superiority is a political and
socioeconomic concept, tied to events of recent political,
military, and economic history and to cultural traditions of
countries or groups. This superiority is rapidly transient, as
history shows, whereas the average genotype does not change
rapidly. But racial prejudice has an old tradition of its own,
and is not easy to eradicate."
>And even if you can, that doesn't take care of my other objections.
>One, that such a definition is different from, and much more
>restrictive than what most people think of as "race". So when you run
>around telling people "science has proven there's no such thing as
>race" you're seriously misleading them, because you are not talking
>about what they think you're talking about. And two, your definition
>of race is unstable, in that if there were two separate races, and they
>mixed even slightly, then they would instantly stop being separate
>races. What good is a definition like that, unless you are absolutely
>intent on running around shouting "there's no such thing as race"?
I'm not at all intent on running around shouting anything. You are,
however, quite caught up in your intent of not only making sure
that the concept of race outlives its scientific basis, but also confers
some sort of caste definition in the process, base upon intellectual
fitness.
>>[Singer]
>>>And, the groups that we have divided the world into were based,
>>>initially, upon the theory of multiple, separate evolutions for
>>>man, which led us to imagine a =much= greater genetic disparity
>>>than exists.
>
>>[Lathrop]
>>>No, you have it backwards. The multiple, separate evolution theory was
>>>a (failed) attempt to explain observed racial differences.
>
>>And the fissions that are so keenly obsessed over by racists are
>>are also "a (failed) attempt to explain observed racial differences."
>
>Lane, you are in denial. The primary concern of Cavalli-Sforza's book
>is mapping those "fissions",
Of course. The aim of the book is to trace the migration of early
anatomically Modern humans.
>and he repeatedly affirms that the deepest
>of them lies between Africans and non-Africans. I've quoted him
>several times to that effect, but you simply refuse to acknowledge it.
I have made no such denial. I responded that it is a very important issue
because it contributes to our knowledge that Africa was indeed the
birthplace of our species - only Africa. Other than that I have
really nothing to say about it. Why? What is it you want me
to say?
>The genetic trees in his book consistently have a branch labeled
>"European" or "Caucasian", but you take no notice. Why?
Again, what notice do you want me to take. The authors state that
they are using the names given the various populations by
scientists who gathered and published some of the genetic data
used as the foundation of this work, in 1977 and 1984. (p.73)
On page 20 they state that although "the individual can be the unit
of evolutionary study, this requires testing every individual for a
large number of genes, and the amount of information generated
soon becomes prohibitive." As it is, they started with data on
almost 2,000 populations and were forced, for logistical reasons,
to combine them, "Our main criterion in pooling populations for
generating higher categories was geographic, but it was clear
that, especially for populations from the developing world, the
geographic criterion had to be supplemented with general
anthropological information of some kind because populations
of widely different origins occasionally live only short distances
from one another."
>
>>[Lathrop]
>>>>And yes, North Africans group with the Caucasians (as shown in the
>>>>*second* color map, representing Africa, and explicitly stated at the
>>>>beginning of section 3.4 in the text).
>
>>[Singer]
>>>Modern north Africans maybe, but not ancient north Africans. This
>>>map in question represents the world today, or as of 500 years ago
>>>(he clearly states that he attempted to sample populations that
>>>were extant 500 years ago in their present locale).
>
>>[Lathrop]
>>>I don't think I believe this. Did you get this from the book, or do
>>>you have another source?
>
[Singer]
>>HGHG, p.4
>>"Our primary interest is in understanding this evolutionary process.
>>The first task is to describe the existing variation, using a variety
>>of techniques that lend themselves to this work and allow us to test
>>the relevant evolutionary models. We restrict our interest to aboriginal
>>populations, which we define as those already living in the area of
>>study in A.D. 1492."
>
>Yes yes, I knew that the map in question represented the world 500
>years ago. What I was asking for was the source of your assertion that
>"ancient north Africans" were not Caucasian. Was *that* in the book,
>or did you get it from somewhere else?
>
>Why can't you answer my questions as I ask them?
What an intersting tone. I would like to ask you - where do you
get off? Your question was ambiguous enough that I interpreted
it as I did. By the way, Tom, I have asked you many questions
that have gone unanswered. There's no need to be rude.
Ancient north Africans were not Caucasions for the simple reason
that there were no Caucasions 100kya. There were no humans outside
of Africa. The north Africans were, at that time, genetically identical
to subSaharan Africans - in fact, the north Africans =were=
subSaharan Africans who migrated to the north.
More of Tom's questions addressed in a following post.
Singer
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"men remain in ignorance as long as they hate, and they hate unjustly
as long as they remain in ignorance." Tertullian
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