Article

Divergence Population Genetics of Chimpanzees

Department of Genetics, Rutgers the State University of New Jersey, Piscataway, New Jersey, USA.
Molecular Biology and Evolution (Impact Factor: 9.11). 03/2005; 22(2):297-307. DOI: 10.1093/molbev/msi017
Source: PubMed

ABSTRACT

The divergence of two subspecies of common chimpanzees (Pan troglodytes troglodytes and P. t. verus) and the bonobo (P. paniscus) was studied using a recently developed method for analyzing population divergence. Under the isolation with migration model, the posterior probability distributions of divergence time, migration rates, and effective population sizes were estimated for large multilocus DNA sequence data sets drawn from the literature. The bonobo and the common chimpanzee are estimated to have diverged approximately 0.86 to 0.89 MYA, and the divergence of the two common chimpanzee subspecies is estimated to have occurred 0.42 MYA. P. t. troglodytes appears to have had a larger effective population size (22,400 to 27,900) compared with P. paniscus, P. t. verus, and the ancestral populations of these species. No evidence of gene flow was found in the comparisons involving P. paniscus; however a clear signal of unidirectional gene flow was found from P. t. verus to P. t. troglodytes (2Nm = 0.51).

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    • "These mutation rates were:the migration rate parameter m to be symmetric to reduce the number of parameters, as preliminary analyses estimating asymmetric migration rates were poorly resolved. We also ran several preliminary runs with large, flat priors to estimate migration rate and population size[91]. Based on these preliminary analyses, we set the upper bound of a uniform prior that included the entire posterior distribution of each parameter (Additional file 1: "
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    • "For this reason the two Pan species represent particularly relevant models for making estimates of our last common ancestor's behaviour. Bonobos and chimpanzees are themselves closely related, having diverged from one another around 1 to 2.5 million years ago (Won & Hey, 2005;Langergraber et al., 2012;Takemoto et al., 2015). It is thus unsurprising that the two species show many core similarities. "
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    • "For this reason the two Pan species represent particularly relevant models for making estimates of our last common ancestor's behaviour. Bonobos and chimpanzees are themselves closely related, having diverged from one another around 1 to 2.5 million years ago (Won & Hey, 2005;Langergraber et al., 2012;Takemoto et al., 2015). It is thus unsurprising that the two species show many core similarities. "

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