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bioRxiv · 10.1101/2022.10.29.514326

Large effect loci have a prominent role in Darwin's finch evolution

Abstract

A fundamental goal in evolutionary biology is to understand the genetic architecture of adaptive traits and its evolutionary relevance. Using whole-genome data of 3,958 Darwins finches on the Galapagos Island of Daphne Major we identify six loci of large effect that explain 46% of the variation in beak size of Geospiza fortis, a key ecological trait. Allele frequency changes across 30 years at these loci affected beak morphology in two ways. An abrupt change in beak size occurred in Geospiza fortis as a result of natural selection associated with a drought, and a more gradual change occurred in G. scandens as a result of introgressive hybridization. This study demonstrates how large effect loci are a major contributor to the genetic architecture of rapid diversification during adaptive radiations. One Sentence SummaryAllele frequency change at six loci of large effect causes evolutionary change in key ecological traits.

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BibTeXRIS

Enbody, E. D., Sendell-Price, A. T., Sprehn, C. G., Rubin, C.-J., Visscher, P. M., Grant, B. R., Andersson, L.. 2022-10-30. Large effect loci have a prominent role in Darwin's finch evolution. https://doi.org/10.1101/2022.10.29.514326

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