Gametic isolation is thought to play an important role in the evolution of reproductive isolation in broadcast‐spawning marine invertebrates. However, it is unclear whether gametic isolation commonly evolves early in the speciation process or only accumulates after other reproductive barriers are already in place. It is also unknown whether gametic isolation is an effective barrier to introgression following speciation. Here, we used whole‐genome sequencing data and multiple complementary phylogenomic approaches to test whether the well‐documented gametic incompatibilities among the strongylocentrotid sea urchins have limited introgression. We quantified phylogenetic discordance, inferred reticulate phylogenetic networks, and applied the
Hybridization, introgression, and reciprocal gene flow during speciation, specifically the generation of mitonuclear discordance, are increasingly observed as parts of the speciation process. Genomic approaches provide insight into where, when, and how adaptation operates during and after speciation and can measure historical and modern introgression. Whether adaptive or neutral in origin, hybridization can cause mitonuclear discordance by placing the mitochondrial genome of one species (or population) in the nuclear background of another species. The latter, introgressed species may eventually have its own mtDNA replaced or “captured” by other species across its entire geographical range. Intermediate stages in the capture process should be observable. Two nonsister species of Australasian monarch‐flycatchers, Spectacled Monarch (
- NSF-PAR ID:
- 10451690
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 30
- Issue:
- 9
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 2087-2103
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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