I think race is a continuum (probably several) rather than an all or none classification.
Where is the person on the continuum that has 10% Asian, 60% European, 20% African and say the last 10% being a mix of Polynesian and American Eskimo?
My definition: skin color and it's covariates arising from shared ancestry and evolution via reproductive isolation over time.
When were blacks and Europeans isolated over time?
Australian Aboriginals were isolated for 40-60 thousand years (I believe). When do they become 'not a race' now that they've been mixing genetically with Europeans for a few hundred years? What race would the offspring be of an Aussie Aboriginal who married a European of the above mix of ancestors?
Steve Sailor's definition is not bad either:
A racial group is an extended family that is inbred to some degree.
So when do European Royals become a separate race?
If anyone doubts race can be categorized biologically / genetically, you should read Before the Dawn:
http://www.vdare.com/articles/nicho...-milestone-on-long-road-back-from-race-denial
It's not the only opinion out there, and just from the link, I can see all kinds of problems already:
Last September, for instance, Wade's article about University of Chicago geneticist Bruce T. Lahn's discovery of two human brain genes that have been evolving differently on different continents earned Lahn global publicity. (Researchers Say Human Brain Is Still Evolving, September 8, 2005)
In contrast, just before Christmas, the Hap-Map team led by Robert Moyzis of UC Irvine released an even more important paper listing 1,800 genes, many of them related to cognition, that have similarly been diverging racially within the last 50,000 years. But Wade, who can't work 365 days of the year, didn't get a chance to cover it when it came out. So Moyzis's landmark study has largely been ignored.
That there are diverging and emerging genetic lines is not in question. The question is when do these genetic lines diverge enough to truly represent a subspecies. And if you have continual remixing, how many races are you going to divide the human population into?
Let me give you a hypothetical. Suppose it's determined that someone with a certain cluster of genetic identifiers successfully predicts the person will appear as a Negro and someone with another cluster of genetic identifiers will predictably appear to be of Asian descent. You then determine the amount of genetic differences between the two groups.
Now you take two people of European descent and find they have the same % of genetic differences between them, but they are traditionally considered to be from the same race.
Why are the 4 of them not 4 different races?
You've chosen outward appearance. Genetically within the human population, you've simply chosen to arbitrarily single out certain unimportant genetic differences.
Socially, those differences have been important. But they are not important genetic divisions. Blood groups, for example, are much more significant genetic differences when it comes to reproductive compatibility, an important biologic distinction when considering species and sub-species.
As for the claim brain genetic lines are diverging, does that translate into intelligence being the racial divide? Maybe I'm a different race from my siblings, after all, we all had different IQs.