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pinkharrier wrote; Hmmm. Does this apply to life in general (such as wild dogs and dingos etc) or just humans?
pinkharrier wrote; So what is your take on police descriptions? Be precise please.

mcgruff wrote:So what do we actually find?[/i]
- human genetic diversity is unusually low for a primate species (as a result of recent near-extinction events)
- you can pick any population at random anywhere on the planet and you will find almost all possible human variation within that group
- more variation within a given population than between populations
- multiple independent clines*
- if you use enough markers (many thousands) you can identify which population an individual belongs to with very high accuracy (but not with smaller numbers of markers)
Further technical comment: you may have read the misleading statistic, spread by the intellectually dishonest Lewontin, that 85% percent of all human genetic variation occurs within groups and only 15% between groups. The statistic is true, but what is often falsely claimed is that this breakup of variances (larger within group than between group) prevents any meaningful genetic classification of populations. This false conclusion neglects the correlations in the genetic data that are revealed in a cluster analysis. See here for a simple example which shows that there can be dramatic group differences in phenotypes even if every version of every gene is found in two groups -- as long as the frequency or probability distributions are distinct. Sadly, understanding this point requires just enough mathematical ability that it has eluded all but a small number of experts.)
See data sources here http://www.goodrumj.com/RFaqHTML.html also, set out here by Woodley. http://tinyurl.com/4yoersbTable 1. Comparative figures for the genetic diversity of humans and a variety of other large mammals (sampled across much or all of their range except as noted), based on autosomal microsatellites (He and Ho = expected and observed heterozygosity, respectively):
Species He Ho
Humans [18] -- 0.776
Humans [19] -- 0.70-0.76
Humans [20] -- 0.588-0.807
Chimpanzees [21] 0.78 0.73
Chimpanzees [22] -- 0.630
African buffalo [23] 0.759 0.729
Leopards [24] 0.36-0.80 --
Jaguars [25] 0.739 --
Polar bears [26] 0.68 --
Brown bears (N. America) [27] 0.26-0.76 0.30-0.79
Brown bears (Scandinavia) [28] 0.709 0.665
Canada lynx [29] -- 0.66
Bighorn sheep [30] 0.681 0.566
Coyote [31] 0.675 0.583
Gray wolf (N. America) [32] 0.620 0.528
Pumas [33] -- 0.52
Bonobos [34] 0.59 0.48
Dogs (42 breeds) [35] 0.616 0.401
African wild dogs [36] 0.643 --
Australian dingo [37] 0.47 0.42
Wolverines (N. America) [38] 0.42-0.68 --
Wolverines (Scandinavia) [39] -- 0.27-0.38
Elk (North America) [40] 0.26-0.53 --
Keeping the preceding caveats in mind, these are qualitative guidelines suggested by Sewall Wright for interpreting FST:
“The range 0 to 0.05 may be considered as indicating little genetic differentiation.
The range 0.05 to 0.15 indicates moderate genetic differentiation.
The range 0.15 to 0.25 indicates great genetic differentiation.
Values of FST above 0.25 indicate very great genetic differentiation.” [81]
Table 2.
Here are some comparative figures for humans and other species (again, sampled across most or all of their ranges except as noted), based on autosomal microsatellites:
Species FST
Gray wolves (North America) [82] 0.168
Pumas [83] 0.167 (mean pairwise)
Humans (14 populations) [84] 0.155 (AMOVA)
Asian dogs (11 breeds) [85] 0.154
European wildcats (Italy) [86] 0.13
Humans (44 populations) [87] 0.121 (AMOVA)
Coyotes (North America) [88] 0.107
Wolverines (North America) [89] 0.067 (mean pairwise)
Jaguars [90] 0.065
African buffalo [91] 0.059
Polar bears [92] 0.041 (mean pairwise)
Canada lynx [93] 0.033
Humpback whales [94] 0.026 (mean pairwise)
Biowatch wrote:1. Have you heard of the Lewontin Fallacy? Read Cambridge geneticist AWF Edwards' paper on it, or Steve Hsu's discussion here
Although there exist human populations that differ in the proportions of particular alleles present, this fact does not support claims that ‘race’, as it is usually understood, is a biological rather than a social concept. Although there are differences in proportions of alleles in those races usually recognised in contemporary western social discourse (folk-racial categories), these differences are no more biologically significant than are the genetic differences that exist between populations that are not socially recognised as races (populations that do not correspond to folk-racial categories). This implies that whatever average genetic differences exist between the populations called ‘races’ in ordinary social discourse, those genetic differences are not what account for the folk-racial categories in use today. Despite recent research sometimes taken to imply otherwise, folk-racial categories – which remain of fundamental importance to people's life-prospects – remain social categories and not biological categories.
Biowatch wrote:2. What about the genetic diversity in comparison to other species which have sub-species or races?
The fact that, given enough genetic data, individuals can be correctly assigned to their populations of origin is compatible with the observation that most human genetic variation is found within populations, not between them. It is also compatible with our finding that, even when the most distinct populations are considered and hundreds of loci are used, individuals are frequently more similar to members of other populations than to members of their own population. Thus, caution should be used when using geographic or genetic ancestry to make inferences about individual phenotypes.

Populations that exist at the boundaries of these continental divisions are sometimes the most difficult to categorize simply. For example, east African groups, such as Ethiopians and Somalis, have great genetic resemblance to Caucasians and are clearly intermediate between sub-Saharan Africans and Caucasians [5]. The existence of such intermediate groups should not, however, overshadow the fact that the greatest genetic structure that exists in the human population occurs at the racial level...
Two arguments against racial categorization as defined above are firstly that race has no biological basis [1,3], and secondly that there are racial differences but they are merely cosmetic, reflecting superficial characteristics such as skin color and facial features that involve a very small number of genetic loci that were selected historically; these superficial differences do not reflect any additional genetic distinctiveness [2]. A response to the first of these points depends on the definition of 'biological'. If biological is defined as genetic then, as detailed above, a decade or more of population genetics research has documented genetic, and therefore biological, differentiation among the races. This conclusion was most recently reinforced by the analysis of Wilson et al. [2]. If biological is defined by susceptibility to, and natural history of, a chronic disease, then again numerous studies over past decades have documented biological differences among the races. In this context, it is difficult to imagine that such differences are not meaningful. Indeed, it is difficult to conceive of a definition of 'biological' that does not lead to racial differentiation, except perhaps one as extreme as speciation.
Biowatch wrote:What does Kaplan mean by biological categories? See Risch et al:Populations that exist at the boundaries of these continental divisions are sometimes the most difficult to categorize simply. For example, east African groups, such as Ethiopians and Somalis, have great genetic resemblance to Caucasians and are clearly intermediate between sub-Saharan Africans and Caucasians [5]. The existence of such intermediate groups should not, however, overshadow the fact that the greatest genetic structure that exists in the human population occurs at the racial level...
Two arguments against racial categorization as defined above are firstly that race has no biological basis [1,3], and secondly that there are racial differences but they are merely cosmetic, reflecting superficial characteristics such as skin color and facial features that involve a very small number of genetic loci that were selected historically; these superficial differences do not reflect any additional genetic distinctiveness [2]. A response to the first of these points depends on the definition of 'biological'. If biological is defined as genetic then, as detailed above, a decade or more of population genetics research has documented genetic, and therefore biological, differentiation among the races. This conclusion was most recently reinforced by the analysis of Wilson et al. [2]. If biological is defined by susceptibility to, and natural history of, a chronic disease, then again numerous studies over past decades have documented biological differences among the races. In this context, it is difficult to imagine that such differences are not meaningful. Indeed, it is difficult to conceive of a definition of 'biological' that does not lead to racial differentiation, except perhaps one as extreme as speciation.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC139378/

mcgruff wrote:@Biowatch
Nobody is saying there is no variation. However, variation is not the same thing as race. People always get the two mixed up.
If you are to prove the existence of race you would have to demonstrate distinct populations with unique genetic profiles.
However, this can't be done. There is no such thing as race in humans, just multiple intersecting clines.


pinkharrier wrote:I'd like an example of race (humans excluded).
pinkharrier wrote:And other examples of variation besides humans.
pinkharrier wrote:And finally, to define the variations in humans, what terms (if any) do you use?



mcgruff wrote:@Biowatch
Nobody is saying there is no variation. However, variation is not the same thing as race. People always get the two mixed up.
If you are to prove the existence of race you would have to demonstrate distinct populations with unique genetic profiles.
However, this can't be done. There is no such thing as race in humans, just multiple intersecting clines.
It appears that those who attempt to deconstruct the concept of race by
gratuitously burdening it with essentialist connotations (‘‘discrete’’, ‘‘non-overlapping’’,
‘‘discontinuous’’, ‘‘defined by racial markers’’, ‘‘racial genes’’, etc.) are
unaware that their criticism has already been addressed by Dobzhansky more than
40 years ago:
Professor Fried has correctly pointed out that there is no careful and objective
definition of race that would permit delimitation of races as exact, nonoverlapping,
discrete entities. Indeed, such criteria do not exist because if they did,
we would not have races, we would have distinct species. (Dobzhansky in Mead
1968, 165)
In fact, Dobzhansky’s argument should be taken one step further: the essentialist
requirement is so unrealistically demanding that, if this criterion were applied, even
the species concept would fail to pass muster: ‘‘

Biowatch wrote:Did you read the paper I cited above?
Biowatch wrote:Population genetics studies consistently show that when you aggregate dna from individuals around the world they fall into identifiable groups/clusters - which correspond to commonly recognised human races. You can call them varieties if you prefer that term.
Biowatch wrote:http://infoproc.blogspot.com/2009/06/genetic-clustering-40-years-of-progress.html

mcgruff wrote:Do you dispute that the gene map is a series of multiple intersecting clines each following their own selective pressures? Such a pattern does allow an individual to be reliably triangulated to a population (but only if you use many thousands of markers) but that, clearly, is not race. If you used this as your definition of genetic uniqueness you would end up with hundreds of thousands of different races.
mcgruff wrote:Are you serious? "Some guy on a blog" is an authority on race?
Interesting reference to Cavalli-Sforza.Do you know what he had to say about race?
"The classification into races has proved to be a futile exercise for reasons that were already clear to Darwin"
--Cavalli-Sforza
The color map of the world shows very distinctly the differences that we know exist among the continents: Africans (yellow), Caucasoids (green), Mongoloids… (purple), and Australian Aborigines (red). The map does not show well the strong Caucasoid component in northern Africa, but it does show the unity of the other Caucasoids from Europe, and in West, South, and much of Central Asia” [The History and Geography of Human Genes , p. 136]

Dr. Stephen O'Brien, a geneticist at the National Cancer Institute, said that the conclusion that race was not a valid concept ''comes from honest and brilliant people who are not population geneticists.''
''That doesn't mean they are insincere,'' Dr. O'Brien said. ''It's just that they haven't really looked at it. What is happening here is that Neil and his colleagues have decided the pendulum of political correctness has taken the field in a direction that will hurt epidemiological assessment of disease in the very minorities the defenders of political correctness wish to protect.''
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