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Title: Genomic architecture and introgression shape a butterfly radiation
We used 20 de novo genome assemblies to probe the speciation history and architecture of gene flow in rapidly radiatingHeliconiusbutterflies. Our tests to distinguish incomplete lineage sorting from introgression indicate that gene flow has obscured several ancient phylogenetic relationships in this group over large swathes of the genome. Introgressed loci are underrepresented in low-recombination and gene-rich regions, consistent with the purging of foreign alleles more tightly linked to incompatibility loci. Here, we identify a hitherto unknown inversion that traps a color pattern switch locus. We infer that this inversion was transferred between lineages by introgression and is convergent with a similar rearrangement in another part of the genus. These multiple de novo genome sequences enable improved understanding of the importance of introgression and selective processes in adaptive radiation.  more » « less
Award ID(s):
1736026
PAR ID:
10122822
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
366
Issue:
6465
ISSN:
0036-8075
Page Range / eLocation ID:
p. 594-599
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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