Dispersal responses override density effects on genetic diversity during post-disturbance succession
journal contributionposted on 2016-03-30, 00:00 authored by A L Smith, E L Landguth, C M Bull, S C Banks, M G Gardner, Don DriscollDon Driscoll
Dispersal fundamentally influences spatial population dynamics but little is known about dispersal variation in landscapes where spatial heterogeneity is generated predominantly by disturbance and succession. We tested the hypothesis that habitat succession following fire inhibits dispersal, leading to declines over time in genetic diversity in the early successional geckoNephrurus stellatus. We combined a landscape genetics field study with a spatially explicit simulation experiment to determine whether successional patterns in genetic diversity were driven by habitat-mediated dispersal or demographic effects (declines in population density leading to genetic drift). Initial increases in genetic structure following fire were likely driven by direct mortality and rapid population expansion. Subsequent habitat succession increased resistance to gene flow and decreased dispersal and genetic diversity inN. stellatus. Simulated changes in population density alone did not reproduce these results. Habitat-mediated reductions in dispersal, combined with changes in population density, were essential to drive the field-observed patterns. Our study provides a framework for combining demographic, movement and genetic data with simulations to discover the relative influence of demography and dispersal on patterns of landscape genetic structure. Our results suggest that succession can inhibit connectivity among individuals, opening new avenues for understanding how disturbance regimes influence spatial population dynamics.
JournalProceedings. Biological sciences
Article numberARTN 20152934
Pagination20152934 - ?
Link to full text
Publication classificationC Journal article; C1 Refereed article in a scholarly journal
Copyright notice2016, Royal Society Publishing
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Science & TechnologyLife Sciences & BiomedicineBiologyEcologyEvolutionary BiologyLife Sciences & Biomedicine - Other TopicsEnvironmental Sciences & Ecologydensity dependencefirehabitat fragmentationlandscape geneticsmovement ecologydemographic population modelLIZARDFLOWDIFFERENTIATIONCONNECTIVITYINFERENCEPATCHESMATRIXMODEL