Comparative multi-locus phylogeography confirms multiple vicariance events in co-distributed rainforest frogs

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 279; no. 1730; pp. 991 - 999
• Main Authors: Bell, Rayna C, MacKenzie, Jason B, Hickerson, Michael J, Chavarría, Krystle L, Cunningham, Michael, Williams, Stephen, Moritz, Craig
• Format: Journal Article
• Language: English
• Published: England Royal Society 07.03.2012; The Royal Society
• Subjects: Animal migration behavior; Animals; Anura; Anura - genetics; Anura - physiology; Australia; Australia Wet Tropics; Bayes Theorem; Biological taxonomies; Community Phylogeography; DNA, Mitochondrial - chemistry; Evolutionary genetics; Frogs; Gene Flow; Genetic loci; indigenous species; Lineage Divergence; Markov Chains; Mitochondrial DNA; Paleoclimatology; Phylogeography; Population Density; Population Dynamics; population size; rain forests; refuge habitats; Sequence Analysis, DNA; Species; Taxa; Tropical Climate; Tropical rain forests; tropics; Australia
• ISSN: 0962-8452; 1471-2954
• DOI: 10.1098/rspb.2011.1229

Though Pleistocene refugia are frequently cited as drivers of species diversification, comparisons of molecular divergence among sister species typically indicate a continuum of divergence times from the Late Miocene, rather than a clear pulse of speciation events at the Last Glacial Maximum. Community-scale inference methods that explicitly test for multiple vicariance events, and account for differences in ancestral effective population size and gene flow, are well suited for detecting heterogeneity of species' responses to past climate fluctuations. We apply this approach to multi-locus sequence data from five co-distributed frog species endemic to the Wet Tropics rainforests of northeast Australia. Our results demonstrate at least two episodes of vicariance owing to climate-driven forest contractions: one in the Early Pleistocene and the other considerably older. Understanding how repeated cycles of rainforest contraction and expansion differentially affected lineage divergence among co-distributed species provides a framework for identifying evolutionary processes that underlie population divergence and speciation.