File(s) under permanent embargo
Coalescent and biophysical models of stepping-stone gene flow in neritid snails
journal contribution
posted on 2012-11-01, 00:00 authored by E D Crandall, Eric Treml, P H BarberMarine species in the Indo-Pacific have ranges that can span thousands of kilometres, yet studies increasingly suggest that mean larval dispersal distances are less than historically assumed. Gene flow across these ranges must therefore rely to some extent on larval dispersal among intermediate 'stepping-stone' populations in combination with long-distance dispersal far beyond the mean of the dispersal kernel. We evaluate the strength of stepping-stone dynamics by employing a spatially explicit biophysical model of larval dispersal in the tropical Pacific to construct hypotheses for dispersal pathways. We evaluate these hypotheses with coalescent models of gene flow among high-island archipelagos in four neritid gastropod species. Two of the species live in the marine intertidal, while the other two are amphidromous, living in fresh water but retaining pelagic dispersal. Dispersal pathways predicted by the biophysical model were strongly favoured in 16 of 18 tests against alternate hypotheses. In regions where connectivity among high-island archipelagos was predicted as direct, there was no difference in gene flow between marine and amphidromous species. In regions where connectivity was predicted through stepping-stone atolls only accessible to marine species, gene flow estimates between high-island archipelagos were significantly higher in marine species. Moreover, one of the marine species showed a significant pattern of isolation by distance consistent with stepping-stone dynamics. While our results support stepping-stone dynamics in Indo-Pacific species, we also see evidence for nonequilibrium processes such as range expansions or rare long-distance dispersal events. This study couples population genetic and biophysical models to help to shed light on larval dispersal pathways.
History
Journal
Molecular ecologyVolume
21Issue
22Pagination
5579 - 5598Publisher
WileyLocation
Chichester, Eng.Publisher DOI
ISSN
0962-1083eISSN
1365-294XLanguage
engPublication classification
C Journal article; C1.1 Refereed article in a scholarly journalCopyright notice
2012, Blackwell PublishingUsage metrics
Categories
Keywords
Animal DistributionAnimalsBayes TheoremEcosystemGene FlowGenetic VariationGenetics, PopulationGeographyLarvaModels, GeneticPacific IslandsSnailsScience & TechnologyLife Sciences & BiomedicineBiochemistry & Molecular BiologyEcologyEvolutionary BiologyEnvironmental Sciences & Ecologyamphidromyhabitat preferenceIndo-PacificIsolation by distancemodel selectionSouth PacificCORAL-REEF FISHPELAGIC LARVAL DURATIONMAXIMUM-LIKELIHOOD-ESTIMATIONPOPULATION-STRUCTURETROPICAL PACIFICMIGRATION RATESUNSAMPLED POPULATIONSDELAYED METAMORPHOSISPROPAGULE DISPERSALMARINE POPULATIONSEcology
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC