Critical Progress
Critical in the history of molecular anthropology:
- That molecular phylogenetics could compete with comparative anthropology for determining the proximity of species to humans.
- Wilson and King realized in 1975, that while there was equity between the level of molecular evolution branching from chimp to human to putative LCA, that there was an inequity in morphological evolution. Comparative morphology based on fossils could be biased by different rates of change.
- Realization that in DNA there are multiple independent comparisons. Two techniques, mtDNA and hybridization converge on a single answer, chimps as a species are most closely related to humans.
- The ability to resolve population sizes based on the 2N rule, proposed by Kimura in the 1950s. To use that information to compare relative sizes of population and come to a conclusion about abundance that contrasted observations based on the paleontological record. While human fossils in the early and middle stone age are far more abundant than Chimpazee or Gorilla, there are few unambiguous chimpanzee or gorilla fossils from the same period
Loci that have been used in molecular phylogenetics:
- Cytochrome C
- Serum Albumin
- Hemoglobin - Braunitizer, 1960s, Harding et al. 1997
- Mitochondrial D-loop - Wilson group, 1980, 1981, 1984, 1987, 1989, 1991(posthumously) - TMRCA about 170 kya.
- Y-chromosome
- HLA-DR - Ayala 1995 - TMRCA for locus is 60 million years.
- CD4 (Intron) - Tishkoff, 1996 - most of the diversity is in Africa.
- PDHA1 (X-linked) Harris and Hey - TMRCA for locus greater than 1.5 million years.
Xlinked loci: PDHA1, Xq21.3, Xq13.3, Zfx, Fix, Il2rg, Plp, Gk, Ids, Alas2, Rrm2p4, AmeIX, Tnfsf5, Licam, and Msn
Autosomal:Numerous.
Read more about this topic: Molecular Anthropology, History
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