From the Results section:
Our divergence time estimate suggests that the mitochondrial genomes of modern horse breeds shared a common ancestor around 93,000 years ago and no later than 38,000 years ago. A Bayesian skyline plot (BSP) reveals a significant population expansion beginning 6,000-8,000 years ago with an ongoing exponential growth until the present, similar to other domestic animal species. Our data further suggest that a large sample of wild horse diversity was incorporated into the domestic population; specifically, at least 46 of the mtDNA lineages observed in domestic horses (73%) already existed before the beginning of domestication about 5,000 years ago.
|Bayesian Skyline Plot of effective population size through time based on the
whole mtDNA sequence from 63 horses. The beginning of the recent effective population
size expansion is marked in red (median 7,000 years BP).
See also: category: horse genetics.