Stephan Peischl

Abstract Gut microbial communities are shaped by the physicochemical gradients and compartmentalization along the gastrointestinal tract. Whether spatially variable selection is strong enough to promote lasting genetic divergence within microbial species subject to migration and clonal expansion remains unclear. We performed a metagenomic population-genetic analysis of roe deer microbiota across metabolically and structurally distinct gut compartments.

Abstract Most species have been through population bottlenecks and range expansions, and the impact of these events on patterns of diversity has been well studied. In particular, it has been shown that initially rare neutral variants could readily fix on the front of range expansions or during bottlenecks, giving genomic signatures looking like selective sweeps.

Abstract Purifying selection is a critical factor in shaping genetic diversity. Current theoretical models only address scenarios of either very weak or strong selection, leaving a significant gap in our knowledge. The effects of purifying selection on patterns of genomic diversity remain poorly understood when selection against deleterious mutations is weak to moderate, particularly when recombination is limited or absent.