Anders Eriksson (Kings College London) - Reconstructing the Genetic Legacy of Past Selection and Migrations in the Human Genome

4:00pm - 5:00pm / Tuesday 10th October 2017 / Venue: Lecture Theatre 1 Life Sciences Building
Type: Seminar / Category: Research / Series: BEEM Seminar
  • Suitable for: Staff and students with an interest in Behaviour, Evolution, Ecology and Microbiology
  • Admission: Free
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Geographic and environmental factors shape migrations, population bottlenecks and local movements of individuals, and thereby the patterns of genetic variation within a species. For humans, large ethnically and geographically diverse genetic datasets have recently become available, including a rapidly increasing number of ancient samples. However, the richness of data presents challenges to methods aimed at analysing differences between small numbers of populations.
I will discuss how spatially explicit models and Bayesian methods of inference can be used to address some of these difficulties, using the influence of climate and geography on the spread of anatomically modern humans out of Africa into Eurasia and the Americas as a case study, as well as the current limitations of this approach and how they might be addressed. Finally, as humans expanded out of Africa they encountered environments that differed dramatically from those where our species originated. This would have presented both challenges and opportunities, and set the stage for adaptation. However, the effects of specific adaptations on genetic variation can be confounded by the general demographic response to the new environments, such as local population bottlenecks. I will discuss how climate-informed spatial models can help to disentangle these factors by providing clear signatures of different forms of selection in specific geographic contexts.