Using ancient DNA to track the evolution of today’s humans
As humans migrated throughout the world, they experienced new and challenging environments. They also created new environments for themselves, for example through the development of agriculture. The traces of genetic adaptation to these environments can be seen in our genomes and phenotypes today. By analyzing ancient DNA–genetic data directly from ancient humans–we are able to watch evolution in action, and observe adaptation as it happens. Here, I summarize what these data have told us about human evolution, and what they might tell us in the future.
In particular, I describe what we’ve learnt about the genetic changes underlying the evolution of stature, body proportions, skin pigmentation, metabolism and immune response, as modern humans migrated into Europe starting around 45,000 years before present. Some of the variation underlying these changes was ancient, some appeared recently, and a small but significant proportion was inherited from our Neanderthal predecessors. In many cases, this variation contributes to variation in phenotype and disease risk among today’s humans. But this is just scratching the surface of the human story and much more remains to be discovered. Finally, I describe some of the key questions that we aim to address in the next few years.