Iain Mathieson is an Assistant Professor of Genetics at the University of Pennsylvania. He trained originally in mathematics and statistics before receiving his PhD in genetics from the University of Oxford and performing postdoctoral research in ancient DNA at Harvard University. His work focuses on the genetic basis, distribution and evolution of complex traits in humans. He uses ancient DNA to record and understand the evolution of complex traits as humans migrated throughout the world, developed agriculture, and created and experienced new environments. In particular, he tries to integrate ancient DNA data with information from medical genetics (e.g. Genome-wide association studies), and anthropology to understand the full picture of how genetics and environment interact today, and interacted in the past, to shape human phenotypic diversity.