Insight into speciation and adaptation in grouse as revealed by whole genome sequencing
(English)Manuscript (preprint) (Other academic)
Understanding the molecular basis of adaption is one of the central goals in evolutionary biology and when investigated across sister species it can provide detailed insight into the mechanisms of speciation. The grouse (subfamily Tetraoninae) constitute an avian lineage whose members inhabit a wide variety of habitats and possess diverse plumage traits and as such offer an interesting case study. Here, we sequence the genomes of 34 individuals comprising three grouse taxa; the willow grouse (Lagopus lagopus lagopus), the red grouse (Lagopus lagopus scoticus) and the rock ptarmigan (Lagopus muta) in order to uncover the genomic architecture of speciation and the genes involved in adaptation. We identify 6 regions, containing 7 genes that show consistent signs of differential selection across the species. These genes are highly involved in a variety of cell processes ranging from stress response to neural, gut, olfactory and limb development. Genome wide neutrality test statistics also reveal a strong signal of population expansion acting across the genomes, which is in line with previous demographic studies in these systems. Additionally, we uncover a 3.5Mb region on chromosome 20 that shows considerably lower levels of differentiation across the three grouse lineages, indicating the action of uniform selection. The Agouti gene, which is integral in the pigmentation pathway, lies at the 5' start of this region hinting at the conserved development of brown plumage across the three taxa. Together, our results provide a key step in the exploration of grouse speciation and adaptation.
Speciation, adaptation, grouse, Tetraoninae, population genomics, FOXP4, Agouti
IdentifiersURN: urn:nbn:se:uu:diva-298415OAI: oai:DiVA.org:uu-298415DiVA: diva2:945908