Living on the edge: Exploring the role of coastal refugia in the Alexander Archipelago of Alaska.

Although islands are of long-standing interest to biologists, only a handful of studies have investigated the role of climatic history in shaping evolutionary diversification in high-latitude archipelagos. In this study of the Alexander Archipelago (AA) of Southeast Alaska, we address the impact of glacial cycles on geographic genetic structure for three mammals co-distributed along the North Pacific Coast. We examined variation in mitochondrial and nuclear loci for long-tailed voles (), northwestern deermice (), and dusky shrews (), and then tested hypotheses derived from Species Distribution Models, reconstructions of paleoshorelines, and island area and isolation.

Phylogeographic structure in long-tailed voles (Rodentia: Arvicolinae) belies the complex Pleistocene history of isolation, divergence, and recolonization of Northwest North America's fauna.

Quaternary climate fluctuations restructured biodiversity across North American high latitudes through repeated episodes of range contraction, population isolation and divergence, and subsequent expansion. Identifying how species responded to changing environmental conditions not only allows us to explore the mode and tempo of evolution in northern taxa, but also provides a basis for forecasting future biotic response across the highly variable topography of western North America. Using a multilocus approach under a Bayesian coalescent framework, we investigated the phylogeography of a wide-ranging mammal, the long-tailed vole, .