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Dentochronological separation estimates for pacific rim populations
Science (New York, N.Y.)
|May 30, 1986
Summary
Dental morphology analysis reveals population genetic separation timelines. Dentochronology estimates American Indian divergence from Asians at 13,000 years ago, supporting archaeological evidence and ruling out European origins.
Area of Science:
- Anthropology
- Genetics
- Paleontology
Background:
- Human migration patterns and population genetics are key areas of anthropological and genetic research.
- Understanding the timing of genetic separation between populations provides insights into human history and dispersal.
Purpose of the Study:
- To estimate the genetic separation dates between various human populations using dental morphology.
- To validate the newly developed method of dentochronology against existing data.
Main Methods:
- Multivariate statistical analysis was applied to dental morphological data from American Indians, Asians, and Pacific Islanders.
- The study utilized dentochronology, a method correlating dental traits with genetic divergence times.
Main Results:
- The estimated fission date for American Indians from Asians is 13,000 +/- 3,000 years ago, aligning with archaeological findings.
- Polynesian separation from Southeast Asians is dated to 5,000 +/- 2,200 years ago, with no derivation from Melanesians.
- Ainu-Jomon originated in Sundaland 14,000 +/- 3,300 years ago, and Africans separated from Asian-Americans 60,000 +/- 6,100 years ago.
Conclusions:
- Dentochronology provides reliable estimates for human population genetic separation.
- The findings support established timelines for human migration and population divergence, particularly for East Asian and Pacific populations.
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