Open AccessGeographic extent of introgression in Sebastes mentella and its effect on genetic population structure
Author(s) -
Saha Atal,
Johansen Torild,
Hedeholm Rasmus,
Nielsen Einar E.,
Westgaard JonIvar,
Hauser Lorenz,
Planque Benjamin,
Cadrin Steven X.,
Boje Jesper
Publication year - 2017
Publication title -
evolutionary applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.776
H-Index - 68
ISSN - 1752-4571
DOI - 10.1111/eva.12429
Subject(s) - introgression , biology , sebastes , population , sympatric speciation , gene flow , ecology , genetic structure , sympatry , genetic divergence , evolutionary biology , genetic variation , genetic diversity , fishery , fish <actinopterygii> , genetics , demography , sociology , gene
Genetic population structure is often used to identify management units in exploited species, but the extent of genetic differentiation may be inflated by geographic variation in the level of hybridization between species. We identify the genetic population structure of Sebastes mentella and investigate possible introgression within the genus by analyzing 13 microsatellites in 2,562 redfish specimens sampled throughout the North Atlantic. The data support an historical divergence between the “shallow” and “deep” groups, beyond the Irminger Sea where they were described previously. A third group , “slope,” has an extended distribution on the East Greenland Shelf, in addition to earlier findings on the Icelandic slope. Furthermore, S. mentella from the Northeast Arctic and Northwest Atlantic waters are genetically different populations. In both areas, interspecific introgression may influence allele frequency differences among populations. Evidence of introgression was found for almost all the identified Sebastes gene pools, but to a much lower extent than suggested earlier. Greenland waters appear to be a sympatric zone for many of the genetically independent Sebastes groups. This study illustrates that the identified groups maintain their genetic integrity in this region despite introgression.