1Department of Anthropology, University of Florida, Gainesville, 2Department of Anthropology, University of Iowa, Iowa City, 3Archaeogenetics Laboratory, Institute of Archaeology of the Academy of Sciences of the Czech Republic, Prague, The Czech Republic, 4Department of Clinical Biochemistry, Faculty of Medicine and Health Sciences, University of Sana’a, Sana’a, Yemen
Friday Morning, 200ABC
The southern dispersal route (SDR) out of Africa posits that anatomically modern humans (AMHs) first left Africa by crossing the southern extent of the Red Sea. Yemen would be the first stop outside Africa. If AMHs did follow the SDR and left modern descendants, one would expect to see deep divergences in the Yemeni mitochondrial gene tree. On the other hand, if AMHs followed the SDR but no modern descendants remain or if AMHs did not pass through Yemen on their route, one would expect more recent divergence dates instead.
We used data from 90 Yemeni mitochondrial genomes from haplogroups L3, M, and N that were sequenced using the Illumina Genome Analyzer IIx as well as 68 additional from a wide-array of haplogroups that were previously sequenced using traditional Sanger sequencing. We used multiple methodologies within the BEAST software package to generate divergence dates. One method, which we took from published literature, used a relaxed clock model and a prior on the tree root, but restricted analyses to the coding region. We also used a novel method that attempts to integrate both the coding and control regions by using multiple substitution models. The dates generated were compared to each other and with previously published dates to test for the effects of different methodologies. Our dates were also compared with archaeological dates to look for consistency between different types of data. We also examined our dates to see if they correlate with periods of climatic change and subsequent population expansions.
Samples sequenced in the study were collected with support of NSF grant BCS-0518530