Widespread hybridization and bidirectional introgression in sympatric species of coral reef fish

Harrison, Hugo B., Berumen, Michael L., Saenz-Agudelo, Pablo, Salas, Eva, Williamson, David H., and Jones, Geoffrey P. (2017) Widespread hybridization and bidirectional introgression in sympatric species of coral reef fish. Molecular Ecology, 26 (20). pp. 5692-5704.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://doi.org/10.1111/mec.14279
 
7
2


Abstract

Coral reefs are highly diverse ecosystems, where numerous closely related species often coexist. How new species arise and are maintained in these high geneflow environments have been long-standing conundrums. Hybridization and patterns of introgression between sympatric species provide a unique insight into the mechanisms of speciation and the maintenance of species boundaries. In this study, we investigate the extent of hybridization between two closely related species of coral reef fish: the common coral trout (Plectropomus leopardus) and the bar-cheek coral trout (Plectropomus maculatus). Using a complementary set of 25 microsatellite loci, we distinguish pure genotype classes from first- and later-generation hybrids, identifying 124 interspecific hybrids from a collection of 2,991 coral trout sampled in inshore and mid-shelf reefs of the southern Great Barrier Reef. Hybrids were ubiquitous among reefs, fertile and spanned multiple generations suggesting both ecological and evolutionary processes are acting to maintain species barriers. We elaborate on these finding to investigate the extent of genomic introgression and admixture from 2,271 SNP loci recovered from a ddRAD library of pure and hybrid individuals. An analysis of genomic clines on recovered loci indicates that 261 SNP loci deviate from a model of neutral introgression, of which 132 indicate a pattern of introgression consistent with selection favouring both hybrid and parental genotypes. Our findings indicate genome-wide, bidirectional introgression between two sympatric species of coral reef fishes and provide further support to a growing body of evidence for the role of hybridization in the evolution of coral reef fishes.

Item ID: 51714
Item Type: Article (Research - C1)
ISSN: 1365-294X
Keywords: ecological genetics, fish, hybridization, natural selection and contemporary evolution, population ecology
Funders: King Abdullah University of Science and Technology (KAUST), National Environmental Research Program (NERP), Australian Research Council (ARC)
Projects and Grants: KAUST CRG-1-2012-BER-002, KAUST OCRF-SPCF-2011-BER-001, ARC DE160101141
Research Data: https://datadryad.org//handle/10255/dryad.138611
Date Deposited: 06 Dec 2017 07:33
FoR Codes: 06 BIOLOGICAL SCIENCES > 0604 Genetics > 060409 Molecular Evolution @ 80%
06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 20%
SEO Codes: 96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960808 Marine Flora, Fauna and Biodiversity @ 100%
Downloads: Total: 2
Last 12 Months: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page