PT  - JOURNAL ARTICLE
AU  - Christopher B. Cole
AU  - Sha Joe Zhu
AU  - Iain Mathieson
AU  - Kay Prüfer
AU  - Gerton Lunter
TI  - Ancient Admixture into Africa from the ancestors of non-Africans
AID  - 10.1101/2020.06.01.127555
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.06.01.127555
4099  - http://biorxiv.org/content/early/2020/06/01/2020.06.01.127555.short
4100  - http://biorxiv.org/content/early/2020/06/01/2020.06.01.127555.full
AB  - Genetic diversity across human populations has been shaped by demographic history, making it possible to infer past demographic events from extant genomes. However, demographic inference in the ancient past is difficult, particularly around the out-of-Africa event in the Late Middle Paleolithic, a period of profound importance to our species’ history. Here we present SMCSMC, a Bayesian method for inference of time-varying population sizes and directional migration rates under the coalescent-with-recombination model, to study ancient demographic events. We find evidence for substantial migration from the ancestors of present-day Eurasians into African groups between 40 and 70 thousand years ago, predating the divergence of Eastern and Western Eurasian lineages. This event accounts for previously unexplained genetic diversity in African populations, and supports the existence of novel population substructure in the Late Middle Paleolithic. Our results indicate that our species’ demographic history around the out-of-Africa event is more complex than previously appreciated.Competing Interest StatementThe authors have declared no competing interest.