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Burri, R.

Publications and source records attributed to Burri, R..

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Interpreting Differentiation Landscapes In The Light Of Long-Term Linked Selection

Identifying genomic regions underlying adaptation in extant lineages is key to understand the trajectories along which biodiversity evolves. However, this task is complicated by evolutionary processes that obscure and mimic footprints of positive selection. Particularly the long-term effects of linked selection remain underappreciated and difficult to account for. Based on patterns emerging from recent research on the evolution of differentiation across the speciation continuum, I illustrate how long-term linked selection affects the distribution of differentiation along genomes. I then argue that a comparative population genomics framework that exploits emergent features of long-term linked selection can help overcome shortcomings of traditional genome scans for adaptive evolution, but needs to account for the temporal dynamics of differentiation landscapes.

evolutionary biology

Genome-wide signatures of genetic variation within and between populations - a comparative perspective

Genome-wide screens of genetic variation can reveal signatures of population-specific selection implicated in adaptation and speciation. Yet, unrelated processes such as linked selection arising as a consequence of genome architecture can generate comparable signatures across taxa. To investigate prevalence and phylogenetic stability of linked selection, we took a comparative approach utilizing population-level data from 444 re-sequenced genomes of three avian clades spanning 50 million years of evolution. Levels of nucleotide diversity ({pi}),population-scaled recombination rate ({rho}), genetic differentiation (FST, PBS) and sequence divergence (Dxy) were remarkably similar in syntenic genomic regions across clades. Elevated local genetic differentiation was associated with inferred centromere and sub-telomeric regions. Our results support a role of linked selection shaping genome-wide heterogeneity in genetic diversity within and between clades. The long-term conservation of diversity landscapes and stable association with genomic features make the outcome of this evolutionary process in part predictable.

evolutionary biology