Variation in natural selection, population demography and individual life history in insular plant and bird populations

点击翻译按钮获取中文摘要

Environmental change is a key threat to the conservation of native species and ecosystems but these changes act via multiple paths and interact over evolutionary timescales, and thus require detailed, long-term studies of individuals and populations to characterize and explain. Specifically, change in 1) climate means and extremes and their effect on fitness, 2) the direct effects of humans on habitat type or quality, and 3) the indirect effects of humans on community membership or dominance are underway in virtually all regions of the globe. However, the long-term influence of these changes on the persistence of individual species or production of environmental goods and services remains highly uncertain.  Identifying and disentangling the effects of environmental change in managed and unmanaged bird, mammal and plant populations has been the focus of my work for 32 yrs, because these factors can drive ecological and evolutionary change and the persistence of species. In this proposal, I outline tests of existing theory using two outstanding comparative and cross-sectional studies of plant and animal populations already monitored for 12-44 yrs, including: 1) the most detailed study of the genetics, demography and individual life history of a free-living bird ever undertaken (song sparrows, Melospiza melodia) and 2) the population genetics and demography of Seablush (Plectritis congesta), an annual plant I have studied in = 300 populations across its range in BC, WA and OR. My goals in each study are highly complimentary and include: 1) identifying links between abiotic and biotic drivers of change in population demography, and 2) using this understanding to predict how continued environmental change may influence life history evolution, population growth and species range limits. Achieving these goals will contribute fundamentally to our success in managing and maintaining environmental products and services in future, and also offers rigorous tests of critical predictions in demographic and evolutionary theory as applied to wild populations. Because there is little consensus and limited data available to resolve many issues above, my long-term studies of variation in phenotype, genotype, life history and natural selection offer promising opportunities to graduate students and post-doctoral fellows working at the interface of fundamental and applied ecology and evolution in Canada, Scotland, Switzerland and the United States via my own and former student's labs. My results should continue to be valuable to answering highly complex questions about the ecology and evolutionary dynamics of free-living species, to do so at very modest cost, and to have the potential to dramatically improve management outcomes for rare species that are otherwise impossible to study in detail.**