In a discussion about the events in Baltimore, I asserted that the biological race concept was invalid. This was agreed with by some, and disagreed with by some.
Rather than derail @Wirey's thread, I thought I'd reply to the good Saint Frankenstein's post here.
The points you make here are that race exists as a biological concept because we can a) determine what race somebody is by looking at their DNA, b) determine their race by examining their bone structure and c) due to the existence of race-specific conditions.
I'll go over these one by one.
Ascertaining an Individual's Race from DNA
I assume that you're referring here to genetic markers - particular sequences and fragment length polymorphisms (RFLPs, VNTRs, SNPs, STRs, etc.) which are used in genetic fingerprinting, as well as a variety of other areas.
In fact, we often can ascertain an individual's geographical ancestry based on these genetic markers. But this doesn't imply race exists, as these markers are primarily distributed polymorphically. That is to say, they are found in various different populations in different frequencies. Looking at any individual marker's presence gives us a clue as to an individual's ancestry, but only that.
For example, there is one particular Y-chromosomal lineage, including a set of genetic markers, which is associated with West African populations. The A1 haplogroups, specifically. But it's also been found in seven Yorkshire native men. These people are as 'white' as anything, and have no knowledge of any African ancestry, and no recent common family members. Nevertheless, if we looked at this marker (Y chromosomal lineage) alone, then we would conclude these people were West Africans. (For those interested, it's hypothesised that this marker arrived with a Sub-Saharan African brought to serve on Hadrian's Wall by the Romans.)
This is the case with many such markers, including those inherited maternally (mtDNA), paternally (Y-DNA) and from both parents (autosomal).
Say some particular marker is found in 80% of people in China, 60% of people in Korea, 5% of people in Mongolia. That doesn't give us much information as to where a given individual is from, other than it's more likely they're Chinese than Korean, and much more likely Chinese than Mongolian. But if they also possess another marker, which is found in 60% of Chinese people, 60% of Mongolians and 5% of Koreans, then it's much less likely they're Korean. As it's already unlikely they're Mongolian, then it become more likely they're Chinese. Through adding up lots of these markers, we develop a good estimate for where a person is from, but it's only ever probabilistic.
If a marker arises in a particular population, it tends to spread. Human populations aren't separate enough to keep these things discrete. We must remember that, by current estimates, every human on the planet shares an ancestor around 3,500 years ago.
So there aren't any particular markers which go with a particular 'race'. There may be some for Aboriginal Australians, and for Native Americans. These are, as far as I know, the only large groups at this scale with a common ancestry. So this doesn't support the existence of distinct biological races.
Ascertaining an Individual's Origins from Skeletal Morphology
Morphological differences tend to be distributed clinally. What this means is that they are found at an extreme in a particular population, and become less extreme the further you go from there.
I'm going to invent two entirely hypothetical examples to demonstrate this point.
Firstly, imagine there's a particular lump on the right side of the skull which is pretty pronounced in people from Angola. In the DRCongolese, and in Namibians, it's also found, but is less pronounced, and is only a little rise in South Africans and in Central Africans. There may be some trace of it in Ugandans.
But if I found a skull that had this lump, to any degree, then I could accurately say, yes, this person was a Sub-Saharan African ('black person').
However, if there's a lump on the left side of the skull, which is the most pronounced among Somalis, then it's a different story. This lump would be pretty existent, but less prominent, among Yemenis (not 'black') and Kenyans ('black'). It would be found to some extent among Omanis and Saudis, as well as Tanzanians and Ugandans. It might also be found to have a trace in North African populations, thanks to the spread of Arabs out of the Middle East during the earlier Caliphates.
So if I found a skull with this lump, I wouldn't be able to tell what 'race' this individual was, although I'd be able to say they were probably from such and such a general region.
In reality, all these morphological differences are minute.
So due to the clinal distribution of these traits, as well as skin colour, biochemistry, etc, we can't say that any of them are some kind of 'black' trait or 'white' trait. Just that some are found more commonly, or exclusively, among people who we'd classify in these groups based on sociocultural conditioning. But not in all people of those groups. The first bump would only be found in 'blacks', sure. But it wouldn't be found in West Africans.
Race-specific Conditions
These are often an example of polymorphism again. There are certain disorders which are found much more commonly among groups of certain ancestries. Cystic fibrosis is far more common in 'white people' than other groups. But they exist in other groups.
An oft-cited example is sickle-cell anaemia. This is a hereditary disorder found among West Africans. The evolutionary genetics of it are rather interesting. It is found in people of West African origins. So yes, it is specific to people who we'd call black. But it's not like some trait of 'black people', because Ethiopians don't get it, Somalis don't get it, Zulus don't get it, Tanzanians don't get it. EDIT: But people who have two ancestors from West Africa, along different lines, but are of 99% European ancestry, can get it.
So this also doesn't support the existence of race as a biological concept.
Rather than derail @Wirey's thread, I thought I'd reply to the good Saint Frankenstein's post here.
Yes, there are. If there wasn't, they wouldn't be able to tell what race a person is by their DNA, examining their bones/bone structure, there wouldn't be conditions that are mostly race-specific, etc.
The points you make here are that race exists as a biological concept because we can a) determine what race somebody is by looking at their DNA, b) determine their race by examining their bone structure and c) due to the existence of race-specific conditions.
I'll go over these one by one.
Ascertaining an Individual's Race from DNA
I assume that you're referring here to genetic markers - particular sequences and fragment length polymorphisms (RFLPs, VNTRs, SNPs, STRs, etc.) which are used in genetic fingerprinting, as well as a variety of other areas.
In fact, we often can ascertain an individual's geographical ancestry based on these genetic markers. But this doesn't imply race exists, as these markers are primarily distributed polymorphically. That is to say, they are found in various different populations in different frequencies. Looking at any individual marker's presence gives us a clue as to an individual's ancestry, but only that.
For example, there is one particular Y-chromosomal lineage, including a set of genetic markers, which is associated with West African populations. The A1 haplogroups, specifically. But it's also been found in seven Yorkshire native men. These people are as 'white' as anything, and have no knowledge of any African ancestry, and no recent common family members. Nevertheless, if we looked at this marker (Y chromosomal lineage) alone, then we would conclude these people were West Africans. (For those interested, it's hypothesised that this marker arrived with a Sub-Saharan African brought to serve on Hadrian's Wall by the Romans.)
This is the case with many such markers, including those inherited maternally (mtDNA), paternally (Y-DNA) and from both parents (autosomal).
Say some particular marker is found in 80% of people in China, 60% of people in Korea, 5% of people in Mongolia. That doesn't give us much information as to where a given individual is from, other than it's more likely they're Chinese than Korean, and much more likely Chinese than Mongolian. But if they also possess another marker, which is found in 60% of Chinese people, 60% of Mongolians and 5% of Koreans, then it's much less likely they're Korean. As it's already unlikely they're Mongolian, then it become more likely they're Chinese. Through adding up lots of these markers, we develop a good estimate for where a person is from, but it's only ever probabilistic.
If a marker arises in a particular population, it tends to spread. Human populations aren't separate enough to keep these things discrete. We must remember that, by current estimates, every human on the planet shares an ancestor around 3,500 years ago.
So there aren't any particular markers which go with a particular 'race'. There may be some for Aboriginal Australians, and for Native Americans. These are, as far as I know, the only large groups at this scale with a common ancestry. So this doesn't support the existence of distinct biological races.
Ascertaining an Individual's Origins from Skeletal Morphology
Morphological differences tend to be distributed clinally. What this means is that they are found at an extreme in a particular population, and become less extreme the further you go from there.
I'm going to invent two entirely hypothetical examples to demonstrate this point.
Firstly, imagine there's a particular lump on the right side of the skull which is pretty pronounced in people from Angola. In the DRCongolese, and in Namibians, it's also found, but is less pronounced, and is only a little rise in South Africans and in Central Africans. There may be some trace of it in Ugandans.
But if I found a skull that had this lump, to any degree, then I could accurately say, yes, this person was a Sub-Saharan African ('black person').
However, if there's a lump on the left side of the skull, which is the most pronounced among Somalis, then it's a different story. This lump would be pretty existent, but less prominent, among Yemenis (not 'black') and Kenyans ('black'). It would be found to some extent among Omanis and Saudis, as well as Tanzanians and Ugandans. It might also be found to have a trace in North African populations, thanks to the spread of Arabs out of the Middle East during the earlier Caliphates.
So if I found a skull with this lump, I wouldn't be able to tell what 'race' this individual was, although I'd be able to say they were probably from such and such a general region.
In reality, all these morphological differences are minute.
So due to the clinal distribution of these traits, as well as skin colour, biochemistry, etc, we can't say that any of them are some kind of 'black' trait or 'white' trait. Just that some are found more commonly, or exclusively, among people who we'd classify in these groups based on sociocultural conditioning. But not in all people of those groups. The first bump would only be found in 'blacks', sure. But it wouldn't be found in West Africans.
Race-specific Conditions
These are often an example of polymorphism again. There are certain disorders which are found much more commonly among groups of certain ancestries. Cystic fibrosis is far more common in 'white people' than other groups. But they exist in other groups.
An oft-cited example is sickle-cell anaemia. This is a hereditary disorder found among West Africans. The evolutionary genetics of it are rather interesting. It is found in people of West African origins. So yes, it is specific to people who we'd call black. But it's not like some trait of 'black people', because Ethiopians don't get it, Somalis don't get it, Zulus don't get it, Tanzanians don't get it. EDIT: But people who have two ancestors from West Africa, along different lines, but are of 99% European ancestry, can get it.
So this also doesn't support the existence of race as a biological concept.