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Thomas B Smith

Each of full climate models (excluding vegetation and elevation variables for which there were no future projections) were subsequently projected onto predicted future climate layers from the IPCC 4th Assessment Report A1B climate change scenario for the decades 2050-2060 and 2080-2090. These predictions represent conservative efforts, however, as the predictions of atmospheric CO2 concentrations may be reached much sooner, as current emissions already exceed the trajectories of the highest scenarios. Thus, projections of genetic variation on the 2080-2090 climate scenarios are likely relevant for purposes of our study. From the predictions of genetic variation under current and future climate, we generated a change...
Understanding the environmental contributors to population structure is of paramount importance for conservation in urbanized environments. We used spatially explicit models to determine genetic population structure under current and future environmental conditions across a highly fragmented, human-dominated environment in Southern California to assess the effects of natural ecological variation and urbanization. We focused on 7 common species with diverse habitat requirements, home-range sizes, and dispersal abilities. We quantified the relative roles of potential barriers, including natural environmental characteristics and an anthropogenic barrier created by a major highway, in shaping genetic variation. The...
The project objective is to transfer to California a previously developed prioritization framework that combines intraspecific genetic and morphological variation with traditionally used indices of biodiversity, and test its general utility for conservation prioritization. This project will integrate existing data on intraspecific variation of multiple species in the Santa Monica Mountains National Recreational Area with climate data and space-borne measurements of the environment to identify areas with high intraspecific variation.
Efforts to prioritize conservation areas have typically relied on indices that include levels of endemism, species richness, and degree of threat 1 . However, it has long been recognized that measures of species richne ss alone may fail to capture essential evolutionary processes that promote and sustain diversity 2 - 8 . To avoid extinction in the face of climate change, populations may either move to more favorable habitat, or adaptively respond to changing conditions. Wit h increasing fragmentation of formerly continuous habitat, dispersal to new areas may be severely limited. It is important, therefore, to develop ways of prioritizing regions that include not only areas with high species richness and where species...
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