| fatslob-:O said: 1) You could practically use that argument against any biological division among populations ... (biologists aren't going to stop at just "species" either, they are going to make further classifications in the same species group such as "breeds" and to me "human races" are no different than that of animal "breeds") If we do that for the ENTIRE animal kingdom then human races are not an exception ... 2) And it's these skewed allele frequencies which allows us to categorize these large populations ... Would you categorize the people of East Finland as being more genetically similar to the populations of East Asia or Sub-Saharan Africa compared to the European populations ? 3) I don't argue for "race" as a discontinuous distribution of human genetic diversity. In fact I've always acknowledged that race is not a discontinuous classification for human populations much like how we define each "colour" to be distinct only to find out later that they are just a part of the near continuous visible wavelength spectrum of electromagnetic radiation but that doesn't mean that we still can't group based on "range" ... Not all of us define "race" as genetically "distinct" populations and instead define race as genetically "skewed" populations based off of geographical isolation ... (you call them "clines" but we call it "race") 4) @Bold Rosenberg responds otherwise in another paper ... (this pretty much trivializes your entire argument that the genetic differences between races are not statistically significant not true) |
1) But that isn't true. There are a number of statistical factors which can be used to determine whether or not species are considered to be subdivided into distinct clades.
2) I don't know about the genetic similarities between Finns and other non-European populations. That said, in some other populations, this is the case. Certain populations in Africa share more with Europeans than some other African populations.
3) If you do not argue for distinction between "races", the term race becomes arbitrary, fitting into convenience instead of natural biological divisions. Basically, that means that race is socially determined, not biologically determined.
4) There are a few problems with this:
a) Even in Rosenberg's models, clustering is largely arbitrary. The way Structure works is by allowing an individual to plug in values for the amount of clusters you would like to receive. Rosenberg did this with 2-6 clusters. In doing so, he showed that while 2 clusters does not produce any means to clearly distinguish between clusters, 3-6 all produce similar results with the conclusion that this is an acceptable way of dividing the species. He also does not provide results for potential clustering above 6. Basically, what this means is that a division into three clusters is equally valid to a division into six clusters, and depending on the results for beyond 6 clusters, maybe 20 clusters is equally valid. In fact, it is likely that if you put in 52 clusters, it would come back as highly relevant, as that is the number of populations used. Additionally, Tiskoff (2009) performed similar methodological calculations reporting on up to 14 clusters, including six clusters within Africa. To prioritize any one of these clustering models without further information would be to overstep the bounds of this research.
b) This brings us to the issue of using Structure in the first place. While it is a highly regarded program, the means in which it is being used exists outside its intended bounds. As such, robust evaluation of the program must be performed to ensure that this utility is valid. Rosenberg did perform some tests, however, they did not account for the complexity of human genotypic relationships. As such, a robust test was performed using simulation models to see how Structure handles this type of analysis, and many issues arose: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3183908/
This article shows that when number of clusters is lower than the number of populations (in Rosenberg's case, 52 populations were utilized), the program can sometimes incorrectly cluster data due to the analysis existing outside of the program's bounds. The author hypothesizes that the reason for this is that the program places as many results as possible into homogenous clusters, and fills the remaining clusters with heterogeneous populations. The highly homogenous clusters statistically overwhelm the statistical issues created by the heterogeneous clusters.
This pattern is shown when viewing the African populations I described earlier. Despite these populations being more similar to European populations (based on allele sharing calculations) they are not paired in the same group, indicating that the results within Structure may not be an accurate representation of the similarity between genotypes.
c) Rosenberg's models are not models of the statistical significance of races. His models describe the significance of patterning. Basically, what this means is that his models aren't looking into whether or not the degree of variation between groups is significant to call them biologically distinct, he is only looking to see if he can break the groups up. While the ability to divide a population into smaller groups is relevant to the question at hand, it is not indicative of the biological significance of that division.
d) And finally, we discuss biological significance. First of all, I think it is important to note that Rosenberg does not suggest that the possibility of clustering defines race and in fact says that his work should not be taken as evidence of such. Second, I do not believe that Rosenberg (2005) adequately responds to potential issues with sampling. They seem to expand their loci analysis, but do not sample additional populations. These populations are theorized to potentially fill the "gaps" claimed to exist by Rosenberg. Further, it is worth noting that the second article I posted was released after Rosenberg (2005), so it could be seen as a response to Rosenberg, not the other way around (and in fact, Rosenberg (2005) is specifically referenced in this article). This is supported by additional articles which were released after Rosenberg (2005). So, lets look into this a bit.
There's a lot here, and I'm not really sure how to condense it. I'm going to try to be brief because I don't want to be here all night.
-Fst values for Rosenberg's distinct populations do not support biological differentiation. Utilizing Fst values between continents gives a value of 0.043 which falls in the range of "little to no genetic differentiation" and this value gets lower with different clustering.
-"in a rational classification of biological organisms, the computational possibility to determine group membership does not imply that these groups are meaningful according to biological systematic and evolutionary classification criteria"
-The insufficiency of the modern view of race is highlighted through even Rosenberg, which shows certain groupings which do not match typical social "race" grouping, such as a grouping of many asian populations with European populations.
-One of the issues with the modern system of race (that is, the common application, not the Rosenberg divisions), is that it does not necessarily reflect evolutionary history, but instead geography. Often, physical traits are adaptive to an environment, not an indicator of shared ancestry. ( https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3737365/ )
Overall, the problem with the concept of biological race, is that it is largely abstract. We could divide up the species in hundreds of different ways, but this wouldn't be evidence of "race" on its own. So the question becomes, "if biological race exists in the abstract, how do we apply it?". As I stated in my conversations with other users, concepts which run parallel to race do have some utility. You pointed this out yourself. Now, there is a question of whether the utility of "race" is the best means of wielding this utility, but there is some utility there.
So, what have we said? Variation exists across the species in some form. Race in this context exists based on arbitrary criteria. Application of race is potentially relevant, but also potentially harmful and often not ideal.
As such, where do we go from here? Well, lets talk about the different contexts. In academia, race is a dangerous concept because it is so nebulous. Different schools of thought can break it up differently, and what may be applicable in one application may not be applicable in another. Further, its use runs the risk of either misutilizing these concepts or misrepresenting them. In an academic setting, generally more concrete terms should be used when discussing topics other than the term itself. As such, the use of "race" should be immediately contextualized, or avoided if possible. In the context of medicine, race brings up a number of different challenges. Notably, how the concept of race fits into genetics. No matter what model you utilize, there is a wide variation within "races". As such, it is dangerous to apply racial concepts broadly within medicine without properly testing the validity and the robustness of the "race" hypothesis. Similar to academia, if more specific terms can be used, that is generally ideal.
And in the context of this thread.
I stand my "who cares?". If you wish to hold onto the categorization scheme of race and you take it as an affront for people to essentially disavow that system by allowing free identification (which isn't exactly what this regulation does, but I'll take it to the extreme), I think it needs to be understood that this is a functionless change. There is no real loss of utility to be found in allowing self-identification within an anti-discrimination regulation. At the end of the day, no matter how you identify, you will be treated the same within the context of this school system.
