Genetic researchers from the University of Pennsylvania have combined data from existing archaeological and linguistic studies of Africa with human genetic data to shed light on the demographic history of the continent from which all human activity emerged.

The study reveals not just a clearer picture of the continent's history but also the importance of having independent lines of evidence in the interpretation of genetic and genomic data in the reconstruction of population histories.

The study is published in the current issue of the Proceedings of the National Academy of Sciences.

The results, according to Penn geneticist Sarah Tishkoff, a Penn Integrates Knowledge professor with joint appointments in the schools of Medicine and Arts and Science, is that genetic variation in Africa is structured geographically, and to a lesser extent, linguistically. The findings are consistent with the notion that populations in close geographic proximity that speak linguistically similar languages are more likely to exchange genes.