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Tudo Beleza
Supreme tranceaddict

Registered: Oct 2002
Location: Shimokawa, Hokkaido, Japan
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The Human Race
Given that people can be sorted broadly into groups using genetic data, do common notions of race correspond to underlying genetic differences among populations? In some cases they do, but often they do not. For instance, skin color or facial features--traits influenced by natural selection--are routinely used to divide people into races. But groups with similar physical characteristics as a result of selection can be quite different genetically. Individuals from sub-Saharan Africa and Australian Aborigines might have similar skin pigmentation (because of adapting to strong sun), but genetically they are quite dissimilar.
In contrast, two groups that are genetically similar to each other might be exposed to different selective forces. In this case, natural selection can exaggerate some of the differences between groups, making them appear more dissimilar on the surface than they are underneath. Because traits such as skin color have been strongly affected by natural selection, they do not necessarily reflect the population processes that have shaped the distribution of neutral polymorphisms such as Alus or short tandem repeats. Therefore, traits or polymorphisms affected by natural selection may be poor predictors of group membership and may imply genetic relatedness where, in fact, little exists.
Another example of how difficult it is to categorize people involves populations in the U.S. Most people who describe themselves as African-American have relatively recent ancestors from West Africa, and West Africans generally have polymorphism frequencies that can be distinguished from those of Europeans, Asians and Native Americans. The fraction of gene variations that African-Americans share with West Africans, however, is far from uniform, because over the centuries African-Americans have mixed extensively with groups originating from elsewhere in Africa and beyond.
Over the past several years, Mark D. Shriver of Pennsylvania State University and Rick A. Kittles of Howard University have defined a set of polymorphisms that they have used to estimate the fraction of a person's genes originating from each continental region. They found that the West African contribution to the genes of individual African-Americans averages about 80 percent, although it ranges from 20 to 100 percent. Mixing of groups is also apparent in many individuals who believe they have only European ancestors. According to Shriver's analyses, approximately 30 percent of Americans who consider themselves "white" have less than 90 percent European ancestry. Thus, self-reported ancestry is not necessarily a good predictor of the genetic composition of a large number of Americans. Accordingly, common notions of race do not always reflect a person's genetic background.
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May-15-2004 05:35
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ShadoWolf
ISOS

Registered: Apr 2002
Location: State of Trance
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May-15-2004 05:37
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mndeg
;0
Registered: Aug 2002
Location: IL, United States
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this is pointless, it's irrelevent if science proves that race does not exist
people will always in their mind put people in categories of race, and don't tel lme that's not true
when you meet someone, do you notice if they are a guy or a girl?
same thing with race
| quote: | | Instead of advising other people to open their eyes, take your own advice please. The point is that you can't simply announce that black people are a 'race', primarily because of the differentiation that exists within their 'race'. You come across black people who are different shades of black to other black people, and then there are blacks that are verging on being white and black at the same time - so to speak. There isn't a coherent standard by which you can announce that 'yes, this person is a member of the Asian race'. The differences are far too numerous for there to be a coherent and identifiable concept of race. |
in most places, most people aren't so mixed that they don't know what they are COUGH AMERICA, the reason african-americans are so mixed is because of the hundreds years of being enslaved
___________________

soulful/latin/deep house + jazz
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May-15-2004 05:47
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