TY - JOUR

T1 - Environmental diel variation, parasite loads, and local population structuring of a mixed‐mating mangrove fish

AU - Ellison, Amy

AU - Wright, Patricia

AU - Taylor, D. Scott

AU - Cooper, Chris

AU - Regan, Kelly

AU - Currie, Suzie

AU - Consuegra, Sofia

PY - 2012/6/19

Y1 - 2012/6/19

N2 - Genetic variation within populations depends on population size, spatial structuring, and environmental variation, but is also influenced by mating system. Mangroves are some of the most productive and threatened ecosystems on earth and harbor a large proportion of species with mixed‐mating (self‐fertilization and outcrossing). Understanding population structuring in mixed‐mating species is critical for conserving and managing these complex ecosystems. Kryptolebias marmoratus is a unique mixed‐mating vertebrate inhabiting mangrove swamps under highly variable tidal regimes and environmental conditions. We hypothesized that geographical isolation and ecological pressures influence outcrossing rates and genetic diversity, and ultimately determine the local population structuring of K. marmoratus. By comparing genetic variation at 32 microsatellites, diel fluctuations of environmental parameters, and parasite loads among four locations with different degrees of isolation, we found significant differences in genetic diversity and genotypic composition but little evidence of isolation by distance. Locations also differed in environmental diel fluctuation and parasite composition. Our results suggest that mating system, influenced by environmental instability and parasites, underpins local population structuring of K. marmoratus. More generally, we discuss how the conservation of selfing species inhabiting mangroves and other biodiversity hotspots may benefit from knowledge of mating strategies and population structuring at small spatial scales.

AB - Genetic variation within populations depends on population size, spatial structuring, and environmental variation, but is also influenced by mating system. Mangroves are some of the most productive and threatened ecosystems on earth and harbor a large proportion of species with mixed‐mating (self‐fertilization and outcrossing). Understanding population structuring in mixed‐mating species is critical for conserving and managing these complex ecosystems. Kryptolebias marmoratus is a unique mixed‐mating vertebrate inhabiting mangrove swamps under highly variable tidal regimes and environmental conditions. We hypothesized that geographical isolation and ecological pressures influence outcrossing rates and genetic diversity, and ultimately determine the local population structuring of K. marmoratus. By comparing genetic variation at 32 microsatellites, diel fluctuations of environmental parameters, and parasite loads among four locations with different degrees of isolation, we found significant differences in genetic diversity and genotypic composition but little evidence of isolation by distance. Locations also differed in environmental diel fluctuation and parasite composition. Our results suggest that mating system, influenced by environmental instability and parasites, underpins local population structuring of K. marmoratus. More generally, we discuss how the conservation of selfing species inhabiting mangroves and other biodiversity hotspots may benefit from knowledge of mating strategies and population structuring at small spatial scales.

U2 - 10.1002/ece3.289

DO - 10.1002/ece3.289

M3 - Article

VL - 2

JO - Ecology and Evolution

JF - Ecology and Evolution

SN - 2045-7758

IS - 7

ER -