Extra-European Caucasoid

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A term describing non-European Caucasoids from North Africa, Horn of Africa, West Asia, Central Asia and the Indian subcontinent and their descendants in other parts of the world.

Molecular phylogeny researchers using this term are not necessarily asserting that the members of this group are more closely related to each other than to non-members. The word cluster is used both for sets of populations statistically found by cluster analysis to be genetically more similar to each other than to any other populations in the study, but also used for arbitrary groupings. This makes it is easy to mistake an assumption or artifact for a scientific result.

In The History and Geography of Human Genes by Cavalli-Sforza et al. (1994), the average linkage tree diagram of 42 populations (p.78, Fig.2.3.2.B) shows the set of extra-European Caucasoid sample populations as polyphyletic. Cavalli-Sforza et al. grouped 42 sample populations into 9 reasonably compact clusters, although not necessarily genetically closest, including "Caucasoid (extra-European)", for convenience in further analysis (p.79, section 2.3.c).

As the Arguments against races as lineages section of the Race article notes: "the molecular and biochemical proponents of this model explicitly use racial categories in their initial grouping of samples".

It is also necessary to keep in mind that while molecular systematics resulting from cluster analysis is suggestive of a lineage or clade of populations of common descent from a single past ancestor population, it is not proof of a strictly monophyletic origin unless it is already known from other evidence (often archeological instead of genetic) that the member populations of the cluster then stayed in reproductive isolation from other populations.

[edit] See also

[edit] References

  • Cavalli-Sforza, L.L., Menozzi, P. & Piazza, A. The History and Geography of Human Genes Princeton: Princeton University Press, 1994. ISBN 0-691-08750-4
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