Broad geographic sampling reveals the shared basis and environmental correlates of seasonal adaptation in Drosophila
Abstract
To advance our understanding of adaptation to temporally varying selection pressures, we identified signatures of seasonal adaptation occurring in parallel among Drosophila melanogaster populations. Specifically, we estimated allele frequencies genome-wide from flies sampled early and late in the growing season from 20 widely dispersed populations. We identified parallel seasonal allele frequency shifts across North America and Europe, demonstrating that seasonal adaptation is a general phenomenon of temperate fly populations. Seasonally fluctuating polymorphisms are enriched in large chromosomal inversions and we find a broad concordance between seasonal and spatial allele frequency change. The direction of allele frequency change at seasonally variable polymorphisms can be predicted by weather conditions in the weeks prior to sampling, linking the environment and the genomic response to selection. Our results suggest that fluctuating selection is an important evolutionary force affecting patterns of genetic variation in Drosophila.
Data availability
- All raw sequence data have been deposited to the NCBI short read archive (SRA; BioProject Accession #PRJNA308584; accession numbers for each sample can be found in Supplemental Table 1).- Code to conduct these analyses, primary results files, and code to reproduce the figures are available at https://github.com/machadoheather/dmel_seasonal_RTEC.- VCF files with the raw allele frequencies per population and a R-data file of allele frequencies and effective sample sizes (Nc; compatible with scripts) are available on DataDryad (https://datadryad.org/stash/dataset/doi:10.5061/dryad.4r7b826).
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Data from: Broad geographic sampling reveals predictable, pervasive, and strong seasonal adaptation in DrosophilaDryad Digital Repository, doi:10.5061/dryad.4r7b826.
Article and author information
Author details
Funding
NIH Office of the Director (R01GM100366)
- Dmitri A Petrov
NIH Office of the Director (R35GM118165)
- Dmitri A Petrov
NIH Office of the Director (R01GM100366,R01GM137430)
- Alan Bergland
NIH Office of the Director (F32GM097837,R35GM119686)
- Alan Bergland
European Commission (H2020-ERC-2014-CoG-647900)
- Josefa González
Natural Sciences and Engineering Research Council of Canada (RGPIN-2018-05551)
- Thomas Merritt
Canada Research Chairs (950-230113)
- Thomas Merritt
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Magnus Nordborg, Austrian Academy of Sciences, Austria
Version history
- Received: February 16, 2021
- Accepted: June 21, 2021
- Accepted Manuscript published: June 22, 2021 (version 1)
- Version of Record published: July 1, 2021 (version 2)
Copyright
© 2021, Machado et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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