Journal article
Mixed population genomics support for the central marginal hypothesis across the invasive range of the cane toad (Rhinella marina) in Australia
Molecular ecology, Vol.25(17), pp.4161-4176
09/2016
Handle:
https://hdl.handle.net/2376/103639
PMCID: PMC5021610
PMID: 27393238
Abstract
Understanding factors that cause species' geographic range limits is a major focus in ecology and evolution. The central marginal hypothesis (CMH) predicts that species cannot adapt to conditions beyond current geographic range edges because genetic diversity decreases from core to edge due to smaller, more isolated edge populations. We employed a population genomics framework using 24 235-33 112 SNP loci to test major predictions of the CMH in the ongoing invasion of the cane toad (Rhinella marina) in Australia. Cane toad tissue samples were collected along broad-scale, core-to-edge transects across their invasive range. Geographic and ecological core areas were identified using GIS and habitat suitability indices from ecological niche modelling. Bayesian clustering analyses revealed three genetic clusters, in the northwest invasion-front region, northeast precipitation-limited region and southeast cold temperature-limited region. Core-to-edge patterns of genetic diversity and differentiation were consistent with the CMH in the southeast, but were not supported in the northeast and showed mixed support in the northwest. Results suggest cold temperatures are a likely contributor to southeastern range limits, consistent with CMH predictions. In the northeast and northwest, ecological processes consisting of a steep physiological barrier and ongoing invasion dynamics, respectively, are more likely explanations for population genomic patterns than the CMH.
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Details
- Title
- Mixed population genomics support for the central marginal hypothesis across the invasive range of the cane toad (Rhinella marina) in Australia
- Creators
- Daryl R Trumbo - School of Biological Sciences, Washington State University, Abelson Hall, Room 305, Pullman, WA, 990164, USABrendan Epstein - School of Biological Sciences, Washington State University, Abelson Hall, Room 305, Pullman, WA, 990164, USAPaul A Hohenlohe - Department of Biological Sciences, University of Idaho, Life Sciences South 252, Moscow, ID, 83844, USARoss A Alford - College of Marine and Environmental Sciences, James Cook University, Building 28, Townsville, QLD, 4811, AustraliaLin Schwarzkopf - College of Marine and Environmental Sciences, James Cook University, Building 28, Townsville, QLD, 4811, AustraliaAndrew Storfer - School of Biological Sciences, Washington State University, Abelson Hall, Room 305, Pullman, WA, 990164, USA
- Publication Details
- Molecular ecology, Vol.25(17), pp.4161-4176
- Academic Unit
- Biological Sciences, School of
- Publisher
- England
- Grant note
- P30 GM103324 / NIGMS NIH HHS
- Identifiers
- 99900546692901842
- Language
- English
- Resource Type
- Journal article