Mass of genes rather than master genes underlie the genomic architecture of amphibian speciation.
Details
Serval ID
serval:BIB_390A9598B804
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Mass of genes rather than master genes underlie the genomic architecture of amphibian speciation.
Journal
Proceedings of the National Academy of Sciences of the United States of America
ISSN
1091-6490 (Electronic)
ISSN-L
0027-8424
Publication state
Published
Issued date
07/09/2021
Peer-reviewed
Oui
Volume
118
Number
36
Pages
e2103963118
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Publication Status: ppublish
Abstract
The genetic architecture of speciation, i.e., how intrinsic genomic incompatibilities promote reproductive isolation (RI) between diverging lineages, is one of the best-kept secrets of evolution. To directly assess whether incompatibilities arise in a limited set of large-effect speciation genes, or in a multitude of loci, we examined the geographic and genomic landscapes of introgression across the hybrid zones of 41 pairs of frog and toad lineages in the Western Palearctic region. As the divergence between lineages increases, phylogeographic transitions progressively become narrower, and larger parts of the genome resist introgression. This suggests that anuran speciation proceeds through a gradual accumulation of multiple barrier loci scattered across the genome, which ultimately deplete hybrid fitness by intrinsic postzygotic isolation, with behavioral isolation being achieved only at later stages. Moreover, these loci were disproportionately sex linked in one group (Hyla) but not in others (Rana and Bufotes), implying that large X-effects are not necessarily a rule of speciation with undifferentiated sex chromosomes. The highly polygenic nature of RI and the lack of hemizygous X/Z chromosomes could explain why the speciation clock ticks slower in amphibians compared to other vertebrates. The clock-like dynamics of speciation combined with the analytical focus on hybrid zones offer perspectives for more standardized practices of species delimitation.
Keywords
Multidisciplinary, Haldane’s rule, cryptic species, phylogeography, sex chromosomes, species delimitation
Pubmed
Web of science
Open Access
Yes
Funding(s)
Swiss National Science Foundation / P2LAP3_171818
Swiss National Science Foundation / 31003A_166323
Create date
10/07/2021 21:45
Last modification date
05/10/2021 7:09