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Genetic views on race vary considerably between and within academic disciplines. Genetic views differ from historical ones. Many views are complex, and are distinguished by subtle differences. Often the significance of differences between views is related to the use of race in biomedicine. This article compares the major contemporary views on race. Summary of contemporary views
Do human races exist? What about subspecies/breed? If race had a biological basis, what would it be? The phylogeographic subspecies definition A phylogeographic criteria for 'subspecies' was established in the early 1990s (Avise and Ball, 1990; O’Brien and Mayr, 1991). "members of a subspecies would share a unique, geographic locale, a set of phylogenetically concordant phenotypic characters, and a unique natural history relative to other subdivisions of the species. Although subspecies are not reproductively isolated, they will normally be allopatric and exhibit recognizable phylogenetic partitioning. ... evidence for phylogenetic distinction must normally come from the concordant distributions of multiple, independent genetically based traits." (Miththapala et al., 1996) Total human genetic diversity It is often claimed that human genetic diversity is smaller than that of other mammals. Time frame of modern human evolution Mitochondrial DNA from contemporary humans coalescences to a common ancestor living 150,000 years ago (see Mitochondrial Eve). However, nuclear DNA loci have a range of coalescence times, some predating the origin of modern humans or even hominids. Distribution of genetic variation within/between populations Some scientists have argued there exists more variation within racial groups than between, and therefore human races have no taxonomic value. This opinion can be traced back to a 1972 paper by Richard Lewontin. Some researchers report the variation between racial groups (measured by Sewall Wright's population structure statistic FST) accounts for as little as 5-7% of human genetic variation. This argument was widely popularized after Lewontin's original publication. However, most geneticists now recognize that low FST values do not invalidate the suggestion that there might be different human races because of technical limitations of FST (Edwards, 2003), see Lewontin's Fallacy. Populations within continents are more closely related to one another than to populations on other continents. Genetic variation between races is highly structured (Risch, 2002). Thus, when one considers many points (i.e., genetic loci) of variation one can distinguish groups and allocate people into groups (Bamshad, 2004). Do biologically distinct races exist? Sandra Lee, Joanna Mountain and Barbara Koening believe that genetics will not produce identifiable racial categories. They claim other genetic anthropologists claim that genetics will find identifiable races. Craniofacial Appropriation Controversy in Genetic Clusters Dr. Eduardas Valaitas claims the traditional Races of physical anthropology have been unscientifically appropriated by geneticists. Valaitais, a statistititian from Yale, has made a genetic similarity chart of the human species. His genetic distance chart does not coincide with Cavalli Sforza's genetic distance chart. Valaitais claims to have made a genetic distance chart by actual Euclidean distances given by the data. Valaitais contrasts his work with other genetic distance charts such which he claims were categorized in a priori or predefined groups. Namely, Valaitais accuses other genetic anthropologists of using hand-me-down racial groups from the earlier craniofacial races of the 19th century typologists. In particular, the genetic distance intepretations of Cavalli Sforza have been ridiculed for using "a priori" racial groups such as "Caucasian" not given by the actual genetic data itself. The genetic distance plot of Sforza which mirrors 19th century typological groups, has been used by Arthur Jensen a race and IQ psychologist to promote the idea that the traditional races of craniofacial anthropology have been confirmed by genetics. | |||||||||||||||||||||||||||||||||||||||||||||||||||
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