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Mountaintop island age determines species richness of boreal mammals in the American Southwest

January 1, 2007

Models that describe the mechanisms responsible for insular patterns of species richness include the equilibrium theory of island biogeography and the nonequilibrium vicariance model. The relative importance of dispersal or vicariance in structuring insular distribution patterns can be inferred from these models. Predictions of the alternative models were tested for boreal mammals in the American Southwest. Age of mountaintop islands of boreal habitat was determined by constructing a geographic cladogram based on characteristics of intervening valley barriers. Other independent variables included area and isolation of mountaintop islands. Island age was the most important predictor of species richness. In contrast with previous studies of species richness patterns in this system, these results supported the nonequilibrium vicariance model, which indicates that vicariance has been the primary determinant of species distribution patterns in this system.

Publication Year 2007
Title Mountaintop island age determines species richness of boreal mammals in the American Southwest
DOI 10.1111/j.0906-7590.2007.04721.x
Authors J.K. Frey, M.A. Bogan, Terry L. Yates
Publication Type Article
Publication Subtype Journal Article
Series Title Ecography
Index ID 70029964
Record Source USGS Publications Warehouse