There is strong consensus among scientists that modern humans evolved in Africa and then dispersed throughout Europe and Asia around 60 thousand years ago. Until recently, this process was thought to have occurred without any genetic input from Neanderthals or other archaic humans. In contrast, recent research in anthropological genetics has suggested there were minor levels of genetic interbreeding with Neanderthals and the newly described "Denisovans" from Denisova cave in Siberia. These arguments are based on comparisons of the draft Neanderthal genome to a number of human whole genomes sequences; however, none of the whole human genomes came from the Horn of Africa or southern Arabia, which are regions critical to studies of the first human dispersals out of Africa. It also has been questioned whether the evidence for Neanderthal interbreeding could instead be an artifact of the ancestral human population not randomly breeding (i.e., reflective of genetic structure in the ancient African population).
Using whole genome sequences from Eritrea and Yemen, doctoral student Deven Vyas (University of Florida), under the guidance of Dr. Connie Mulligan, will test the contrasting hypotheses of genetic interbreeding with archaic humans versus ancient population structure in Africa. The latest next-generation sequencing technologies will be utilized to generate whole human genome sequences, and newly developed analytical methods will statistically test support for the two competing hypotheses. The data have significant implications for our understanding of the evolutionary history of humans and our knowledge of the populations and processes that contributed to the modern human gene pool. These novel genetic data from Eritrean and Yemeni individuals will be publicly available to researchers all over the world, facilitating future research. In addition, undergraduate students interested in scientific research will be assisting in this project, continuing the strong tradition of mentoring and training undergraduates to conduct scientific research in the Department of Anthropology's Human Genetics Laboratory at the University of Florida, directed by Dr. Mulligan.