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Title: Data and code associated with: Genomic responses to parallel selection in the eelgrass Zostera marina in adjacent bays
The extent of parallel genomic responses to similar selective pressures depends on a complex array of environmental, demographic, and evolutionary forces. Laboratory experiments with replicated selective pressures yield mixed outcomes under controlled conditions and our understanding of genomic parallelism in the wild is limited to a few well-established systems. Here, we examine genomic signals of selection in the eelgrass Zostera marina across temperature gradients in adjacent embayments. Although we find many genomic regions with signals of selection within each bay, there is little overlap at the SNP level across bays. We do find overlap at the gene level, potentially suggesting multiple mutational pathways to the same phenotype. Using polygenic models we find that some sets of candidate SNPs are able to predict temperature across both bays, suggesting that small but parallel shifts in allele frequencies may be missed by independent genome scans. Together, these results highlight the continuous rather than binary nature of parallel evolution in polygenic traits and the complexity of evolutionary predictability.  more » « less
Award ID(s):
1829976
NSF-PAR ID:
10482466
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Dryad
Date Published:
Subject(s) / Keyword(s):
["FOS: Biological sciences","WGS","Marine ecology","Ecology and Evolution","non-parallel evolution","population genomics","Zostera marina"]
Format(s):
Medium: X Size: 954890872 bytes
Size(s):
["954890872 bytes"]
Sponsoring Org:
National Science Foundation
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