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Posted by Kyle on September 9, 2002 00:46:58 UTC


...just to further that last thought ( that we are one big human family)...

Having said that, clearly we as a ‘big family’ have great genetic and physical diversity which is a predicted outcome from populations under periodic reproductive isolation-- eventually you get localized traits occurring.
However, there is to this day, no clear agreement among anthropologists (who use genetic and physical markers to subdivide humans) as to which traits should be used to make racial distinctions.

These are the three ways anthropologists categorize races:
1. anatomical features, skin color, body shape
2. genetics, frequency of genetic diseases
3. blood/ biochemical traits/ metabolic rate and hormone activity.

Most people use #1. Visible anatomical (what biologists call "phenotypic") differences. But when you use all three methods, the results indicate that there is more genetic and physiological diversity WITHIN the groups (that we call races) as there is BETWEEN them. Maybe that's hard to believe but that’s what the data says.

For example, if you use cephalic index (CI) (skull width/ length x 100) then Chinese get lumped together with Norwegians. If you use the ability to taste the chemical substance PTC, then Navajo Indians are related to certain ethnic West Africans, and Spaniards with Malaysians. There are traits that many disparate (contemporary) people share, which came from common ancestors very far back, much earlier than the more recent development of anatomically-distinct racial differences.

The genes that govern the anatomical differences are believed to be relatively recent adaptations (eg. the loss of skin pigmentation in Caucasians, the epicanthal eyelid folds of Asians)-- some of these differences may not have occurred until as recently as the last ice age 12,000 years ago.

So let’s suppose I had a great great...great great grandfather (distant direct ancestor) with really big ears. He produced 5 children who all had big ears too. They all emigrated to various parts of the world, and I descended from one of them. One of them moved to an equatorial climate where he married a dark-skinned woman. One moved to Asia, one to Europe etc. In each case there was a marriage to a local spouse/ mate.
After many generations the collective offspring would have racial traits that were distinctive to their immediate genetic lineage, but if we tested for the big-eared gene, we would see that it mysteriously connected some people in Europe with some people in Asia etc.

This is exactly what biologists and anthropologists have found to be the case on our planet... there are in fact more genetic similarities that link individuals between races than there are genetic similarities between same race members.

These pan-global similarities were traits that humans shared before leaving the African continent in a series of migratory pulses from about 150,000 years ago up to about 40,000 years ago.


All this prompted a geneticist to once remark:
"There could possibly be more genetic differences between myself and my wife (a member of my same race) than between me and a Kalahari Bushman."


Anyway I just thought that that gives an interesting perspective on things.



Regards,

Kyle

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