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Data from: Spotted stream frog diversification at the Australasian faunal zone interface, mainland versus island comparisons, and a test of the Philippine ‘dual-umbilicus’ hypothesis

Citation

Brown, Rafe M.; Siler, Cameron D. (2013), Data from: Spotted stream frog diversification at the Australasian faunal zone interface, mainland versus island comparisons, and a test of the Philippine ‘dual-umbilicus’ hypothesis, Dryad, Dataset, https://doi.org/10.5061/dryad.466mn

Abstract

Aim: We utilize comprehensive geographical sampling and a new, multilocus dataset to re-examine the biogeography of spotted stream frogs throughout Southeast Asia. We compare patterns of diversification among stream frog populations on land-bridge islands and oceanic islands and we reevaluate a previous ‘dual-invasion’ hypothesis for the origins of several endemic Philippine taxa. Location: Southeast Asia, Sundaland, and the Philippines. Methods: Stream frogs were collected and sequenced for two mitochondrial and two nuclear gene regions. We used summary statistics and phylogenetic networks to characterize the geographic distribution of genetic variation. Phylogenetic relationships and ancestral biogeographic ranges were estimated using Bayesian and likelihood methods. Finally, we used the preferred topology and trees from the posterior distribution of the Bayesian analyses to evaluate a previous biogeographic ‘dual-invasion’ topological hypothesis. Results: In contrast to expectations, we found evidence of highly divergent, demographically stable, and geographically regionalized lineages (including currently unrecognized putative species) in the land-bridge island clade, but minimally divergent, widespread and clinally distributed (with evidence of recent demographic expansion) populations in adjacent oceanic island populations. Novel phylogenetic relationships depart from previous studies and our data strongly reject the previously published ‘dual-invasion’ topological hypothesis. Main: conclusions Our results join a new body of literature suggesting that the biogeographic distribution of species diversity on mainland areas and continental shelf islands may harbor high levels of unrecognized diversity in conspicuous vertebrate groups, whereas adjacent oceanic island archipelagos can and do support naturally occurring widespread species or minimally divergent clades. Although increased sampling coupled with more sophisticated methods indicate that the original individual identities of species previously hypothesized to be involved in the ‘dual-invasion’ scenario may have been incorrect, this mechanism for faunal exchange between the archipelago and adjacent mainland undoubtedly has contributed to the accumulation of endemic vertebrate diversity in the Philippines.

Usage Notes

Location

Southeast Asia
Philippines