Human Races

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Since that's precisely what you're arguing, the paper would appear to undercut your position.

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...the reason is not linked to greater difference within and
between populations though.

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Really? I'm not aware of any good evidence that any of the commonly used differences, apart from skin color, is the result of adaptation.

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So distinctive differences in physiology, bone stucture, muscle
attachment, etc. are just random coincidence and not the
result of some past selective pressure?

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A phylogenetically based race will tend to share a suite of traits, while a race that is characterized only by a common selective environment will not, since different selective pressures vary differently with geography.

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So a population that has been subject to the same selective
pressures will NOT share a set of traits?And two different populations living in environments with
different selective pressures won't diverge (even remotely ...
perhaps I can call it nano-evolution )?If there was concensus in the west for a spherical earth for
two thousand years, how is that people thought Columbus was
going to fall off the egde if he went too far?Sure, the Greeks and other ancient races knew, but in Europe
as recently as, what, three - four hundred years ago, the majority
opinion was Earth was flat.Consensus isn't enough. It can be shaped by political factors
and fear of reprisal.I'll restate my position (hopefully with any contradictions
removed, and consider this my thinking even if my meadering
thought processes have obfuscated my thinking in previous posts).1) Cultural racial membership is defined by the members of a
perceived race (not by outsiders). The UK government is using
a 'self-declaration' race categorisation, and the US hospital
services have performed studies that show, by-and-large, that
self-determined racial categorisation matches standard
admission rankings.2) Cultural racial associations are linked to the history
of the cultural race.3) Cultural races originate in localised geographic regions. Each
geographic region will present somewhat different survival
challenges.4) Extant phenotypic traits that interact with the environment will,
over time, be shaped by the environment. These traits are, by
definition, heritable.5) If there is a noticeable difference in the pehnotypic traits
of one group compared to another, then this must be identifiable
in the coding segments of the genome.We, as humans, are observably different.
Those differences are heritable.
Those differences are what cultural racial concepts refer to.

And what about ....Nature - Not Found"They discovered that the most recent common ancestor of everyone in the sample group lived in Africa 171,500 50,000 years ago. They also found a significant branch in the tree that separates most Africans from non-Africans. This genetic divide probably represents an exodus of people from Africa that took place 52,000 27,500 years ago."

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Quite possibly. Also quite possibly not

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So your rejection of the traits being adaptive is as incorrect
as my suggestion that they are.Can we positively identify ANy traits as adaptive except by
a significant amount of hypothesising?

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A single population subject to the same set of selective pressures will probably share a set of traits. But different selective pressures are unlikely to have exactly the same geographical distribution, which is why the paper you quoted from talks about membership in multiple, overlapping races. Some environmental factors change over very short distances, while others remain similar over thousands of miles.

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And in regard to a biological basis for race, this is more pro
than contra.If geographic separation subjects different groups to different
sets fo selective pressures, then the populations that are
affected by those pressures will share trait sets that populations
elsewhere do not have.

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They didn't.

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Fair enough ... doesn't detract from concensus being a poor
metric for a theory.How about a geocentric solar system then ... or bleeding being
a beneficial therapy ... or ...

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Really? I'm not aware of any good evidence that any of the commonly used differences, apart from skin color, is the result of adaptation.

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Had I stated such a rejection...

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Sorry, mis-interpreted the above as you saying that they
weren't rather than we don't have evidence that they are.

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We can make a good case, but only when there's enough genetic evidence

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Darwin didn't have the luxury of genetic evidence, and yet he could
still infer adaptive traits from observation of traits wrt
environment ... isn't that sufficient? If a trait provides a benefit
of some kind in the environment where it is the norm?Isn't the emergence of differentiation between two populations
of the same species in different locations required by evolutionary
theory ... and it's absence an undermining of such?

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Could you be more specific? ...

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Inuit :- live in harsh, cold environment with limited vegitation.Kalahari Bushmen :- live in harsh, desert environment some game, some
fruit/nuts/edible roots.Celts :- Originated in cold, wet hilly location unsuitable for much
agriculture.The locations on earth are many and varied, and the peoples who
come from different locations are observably different, but
consistent within group.

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It's the evidence that counts, not the consensus

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That's all I was saying. Consensus was raised as though that
made it true ... I am unconvinced by the suggested evidence.

'Genetic approaches to understanding human adaptation to altitude in the Andes.'Talks about the difficulty of determining whether or not
a trait is developmental or 'built-in'.Is that the same as inferring whether a trait is adaptive or
not, if one already knows that the trait is genetically
linked (based of heritability, for example)?If a heritable trait confers an advantage, and only occurs
in individuals who trace their family origins back to
the same location is that insufficient evidence of an adaptive
trait?Off topic maybe?

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"We discovered that rare mutations in LMNA.."

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Who said anything about genetically identicle ... since when did
consistent mean the same?The paper you cited is talking about 'rare mutations'. One would
hardly classify a drosophila with stunted wings as anyhing
but a mutant drosophila, why change the 'rules' for humans?If you have a whole bunch of red-eyed ones and a whole bunch
of white-eyed ones of the same species they are referred to as
strains (aren't they) ... why change the 'rules' for people?

Isn't it likely that light skin was selected for in
low-sunlight regions because darker skin reduces (in the
sense that you need more light to do it) Vit-D synthesis ?Otherwise the 'western europeans' would range in skin tone
across the ful spectrum rather than in the lighter
end, surely.[This message has been edited by Peter, 12-05-2003]

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Just showing that there's a benefit is not usually enough ...
I can't think of any that are markers for racial groups, however.

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This implies that regionally associated, heritable traits
just emerge at random, and leads to the populations originating
in different regions came into being independently of one
another.Genetic evidence points to a migration from Africa coupled with
some populational bottle-necks.If the population that headed out-of-Africa where a single population
then according to what has been suggested in this thread
they would be pretty homogenous.That populations in different regions are observabley different
and these differences are heritable means that something
promoted particular phenotypes in the different regions.The different phenotypes are suggestive of a divergence amongst
the original migrant population.

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That depends on how recently the populations have separated and how much gene flow there is between them.

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Are you saying that the ToE's dependence on differentiation
within a species depends on the above, or whether it happens
or not depends on the above.Some researchers are suggesting that the emergence of modern
humans and apes did not occur as a distinct split, but was generated
over time from an inter-breeding population with increasing
degrees of differentiation.

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Is there any evidence that they do have distinctive, adaptive alleles?

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Inuit are genetically pre-disposed to obesity (i.e. fat deposition)
which is beneficial in a cold climate, and require less calcium
in their diets (recommended calcium levels given to Inuit
children can cause hypercalciuria at significantly higher rates
than seen in non-inuit). They also possess lower incidence of
genes associated with cardio-vascular disorders, which is beneficial
if you want to survive longer with higher body-mass-index.

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This is a better example of more typical human populations. "Bushmen" is not a category that they would use to self-identify

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Agreed, although they have no name for themselves (or none that
they are willing to divulge), but have come to accept the
term (somewhat).The intrusion of Bantu herders into their hunter-gathering lifestyle
pre-dates western interaction with the region, but is not
overly indicative of inter-breeding between the two different
tribal cultures.There is some suggestion that all click-language speakers are
related. http://www.marylandresearch.umd.edu/issues/fall2003/dna.html has:"The connection between populations who speak a click language, the language spoken by the Africans in the film "The Gods Must Be Crazy." The DNA shows that different peoples who use click language but live hundreds of miles apart, may be related. Says Tishkoff, "We have been able to show, for the first time, that the Sandawe of East Africa and bushmen from the south of Africa and the southern bushmen of Botswana, Namibia and South Africa share a recent common ancestry, within about 35,000 years. We speculate the southern bushmen originated in East Africa, and that they both are remnants of a very old group of hunter-gatherers, perhaps the earliest ancestors of modern humans."Which admittedly doesn't say anything about, well, anything in detail
but indicates that there is a genetic means of identifying 'Bushmen'.As for the celts --- well OK, even during the time of the Roman
Empire that was a bit tenuous (and I was thinking of Wales ).Interestingly there is a review on
http://www.2think.org/cavalli-sforza.shtml
which is a little schizophrenic. It states that "The variation among individuals is much greater than the differences among groups. In fact, the diversity among individuals is so enormous that the whole concept of race becomes meaningless at the genetic level", but just prior to that says "once the genes for surface traits such as coloration and stature are discounted".So once we discount the genes for the traits upon which racial
distinctions are usually made, suprisingly, we find no genetic
evidence for race. Does that not seem a little, well, odd.Other selected quotes are :-
"What the eye sees as racial differences - between Europeans and Africans, for example - are mainly adaptations to climate as humans moved from one continent to another. ""Those findings, plus the great genetic distance between present-day Africans and non-Africans, indicate that the split from the African branch is the oldest on the human family tree""All Europeans are thought to be a hybrid population, with 65% Asian and 35% African genes"You cannot have it both ways ... there are either genetically
observable differences that allow us to trace humanity's
origins back to Africa, or there are no significant differences
between races that can be seen in the genome.

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More likely? Yes, I'd say so. But I don't see that it's certain. All northern peoples have straight hair, as far as I know -- would you argue that that must be the result of selection, since without selection they'd show the full range of hair shapes?

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It's actually an issue that I find somewhat confusing.I assume by 'curly hair' you mean the very tight curls associated
most often with those of African or Afro-Carribean descent, rather
than the 'naturally curly hair' of Charlie Brown's would-=be
girlfriend.But eye colour also is a problem for me.From people I know with mixed-raced parents, they all seem to have
the dark eyes and tight curls of that side of the family.
If that is the case all of the time it would suggest that
the genetic controlling this feature are dominant (blue eyes
are a recessive feature I believe).Why have recessive features become dominant in some
populations?How could that happen with significantly inter-breeding gloal populations?

What you have said perturbs me.There is a suggestion that because something
exists in a continuum we must negelect differences
between 'items' in two different points of the
continuum ... like red-light is just electromagnetics isn't it,
no different from UV or X-rays.If the polarised objection to a genetic basis for race is
politically motivated, then it is as objectionalble as using
race for political ends, or promoting creation science in
schools.All of the citations show that differentiating between different
cultural members IS possible at the level of the genome.
Even with the inter-breeding between Zulu, Bantu, and Khosian
people, from fairly narrow geographic ranges.How can one posit differences between different culturally
divided groups as evidence against race?There are objectionable associations with racial determination,
and I cannot see any reason that racial differentiation
should matter on a day-to-day personal basis. It has interest
in tracing human origins, perhaps.My problem in this thread is not that I want there to be
racial distinctions, but that I feel that denial of them is
driven by politics and not by scientific inquiry.

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Where do you get this from sfs or my posts?

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Sorry if I implied that it was your (or SFS's) motivation,
not intentional there.My concern is that there is a great push for there being
no genetic basis for race which doesnt seem to tie up
with what the people who are claiming that are saying elsewhere
in the same papers.If there is no race, how CAN you tell that there are differences
in genomes between African and non-Africans, or that Australian
aborigines are not closely related to modern indigenous Africans.You cannot make ANY arbitrary geographical demarcation and find
a genetic correlation. To take an example from sfs's reply to the
same post that you are replying to) look at a city.Say Dublin, or London, or Paris.There is NO genetic marker available for such a population
because there is a very wide range of lineages that originate
in different geographioc locations.Likewise if the geographic area is too large, or divided by geological barriers this will not be the case.

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In order for "race" to be a useful concept genetically it would have to be supported in such a way that you could not replace "races" with almost any arbitrary grouping

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You cannot replace 'race' with 'almost any arbitrary grouping' unless
I am mis-understanding your use of arbitrary.Take a city population and study their genetic diversity and
it will be all over the map. Sub-divide the same group based
upon assumed racial origin and you'll start to see correlations.If this were not the case genetic distance would not correlate
to geographic distance.Perhaps my use of the word divergence is a little strong,
but there is diversification. If you accpet that the
genetic evidence points to an out-of-africa origin, then
you have to accept diversification.That diversity is forged geographically, and most concepts of
'race' correlate with geographical origin.

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A Khoisan-speaking village may be closer genetically to the Bantu-speaking village next door than it is to the Khoisan-speaking village 50 miles away, but you would label the two Khoisan-speaking villages as part of the same race and the Bantu-speaking village a different race. When you do that, you demonstrate that your labels are cultural, not biological

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No, you demonstrate that neither the Bantu-speeaking not Khosian
speaking villages are representative of the races in question.The history of this relationship, in terms of inter-tribal
marriages, changes the situation.The genetic distance between one Khosian speaking village
and another (assuming one is relatively isolated) provides
a measure of 'out breeding'.

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so who are you going to pick as your "African" race

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Those who, according to at least one of the papers referenced
during this discussion, share alleles that are not present
in Europeans and Asians.There are aprrox. (without looking back) 20 of these.

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How do you classify the descendants who may be genetically a mish mash of dozens of different "races"?

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What has this to do with it?If you have a group of populations with no reproductive barrier
you can get highly embedded crosses, that doesn't mean that a
concept of race is non-existent.I am not arguing that you won't get convergence with significant
inter-breeding, I'm saying that that has not happened to a sufficient
degree to claim that there is no biological basis for race.

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If according to you, one can designate "original lineages" despite massive interbreeding in say London or anywhere else then there should be absolutely no correlation between genetic distance and geographic distance...one should always statically maintain one's race just like a separate species.

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This doesn't make sense, logically.If, in one region you have sufficient inter-breeding to comletely
obscure all traces of original lineages, then in that location
you will have a new, unique trait-set, since the likelihood
of haveing the exact same mix elsewhere would be very small. So
the 'new' lineage would have a geographically traceable origin.If this has not happened sufficiently yet, then you would find
traces of the lineage origins in any case.You cannot start a lineage if you live on opposite sides of
the world (unless you have an inter-national sperm/egg bank
I suppose).

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First off, I don't necessarily think OOA (in the form of purist supporters) is correct but in any event, I can accept diversification without subscribing to the cultural concept of "race".

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Not paying any attention to it and not 'subscribing' to it are
different. I doubt that there is a society anywhere that
doesn't have an ingrained concept of race ... socially constructed
yes, but there.If Out-Of-Africa is incorrect, then human populations emerged
separately in separate locations, and the diversification
would be even more pronounced, since it would be older.

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Oh really? Your own personal definitions of race in this thread have varied from as extreme as African, Asian, Caucasian to 3 individuals composing a potential "race". ...

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Well, yes.No matter how much vagueness there is in a concept of race,
ultimately there is a geographic component. One doesn't think
of the bloke up the steet as of a different race, unless
he's different from all the usual residents ... and the
only reason that someone would be that different are unfortunate
circumstances of disease or other disability, or because
they come from somewhere else ... or their family line comes
from somewhere else.There are people in the US who think of themselves as Irish-American,
or African-American ... almost all racial concepts have a
geographic component (even Dubliners or Berliners).

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Oh really? And this does not apply EVERYWHERE else? Show me a place where you do not have large numbers of lineages orginating from different locations even in relatively isolated populations

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Outside of the US, UK, and Australia pretty much all over.Western Europe has a large degree of inter-mingling, but less
so than the colonies ... but move to the Indian sub-continent
or mainland Asia, or S.America (outside the large
population centres) or Amongst the Native American tribes,
or African tribes ... and the number of inputs will be MUCH less.

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Why is it any less valid to you to have "identity by residence" than race?

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It's not invalid ... but that ISN'T biologically based.You seem to be suggesting that global inter-breeding has been
common across the ages ... I've not seen historical evidence of
this. Human societies have been fairly xenophobic, on the whole.

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The reason for this became apparent when the identity of the markers was considered---the OCA2 gene, part of the test battery, encodes a protein that regulates pigment production, meaning that the marker itself contributed to the phenotype. When this site was excluded from the AA1 calculation, there were no significant differences in the African genomic ancestry of black and white study participants

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So, if you exclude all the bits that make us different
we are the same ...Black and white is too broad, but the above says that the
difference has to be specifically excluded. If there is
significant inter-breeding for a number of generations why expect
there to be clear distinctions left. This is not the
global norm.Added by edit (so as not to do another post):Won't Portuguse have 'African' ancestry even in
portugal too? Certainly in the southern parts, where
the Moors held sway for some considerable time ...
doesn't that history conflate matters?There is also mention of 'African allellic markers', and
of Brazilian people falling between the European and African
AA1 values.Doesn't that mean that there are races, otherwise one could not
speak of allelic markers.[This message has been edited by Peter, 12-15-2003][This message has been edited by Peter, 12-15-2003]

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So, slightly differently from how you've characterized Peter's take on genetics, I'd say that the evidence *against* human races is *not* found in genetic data

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That's more or less what I HAVE been saying.

Thanks, I'll take a look.