Unifying Models of Gene Flow at Multiple Scales in a Well-Studied Vertebrate

该项目将制作(1)联邦威胁鸟类佛罗里达丛林鸦的高分辨率遗传种群结构肖像，以及(2)遗传物质如何通过个体鸟类的扩散在种群内和种群之间移动的详细模型。两个独立的遗传标记系统(微卫星和单核苷酸多态)将被用来测量种群之间的遗传相似和差异，使用来自佛罗里达州3000只个体鸟类的血液样本，并在康奈尔鸟类学实验室的DNA测序设施中进行分析。统计模型将根据任何两个种群当前和历史上的地理关系来预测它们之间的遗传分化程度，模拟模型将预测一个重点种群在与其他种群隔离后的遗传命运。佛罗里达灌木鸦在其剩余的范围内迅速衰落，深受公众的喜爱，也是日益减少的生态系统中的一个关键的“保护伞”物种。公共机构、土地管理者和保护组织都渴望从这个项目中获得结果，以帮助选择那些对物种的持续传播和遗传健康至关重要的“栖息地岛屿”。这项研究还具有独特的基础研究价值，因为它将首次整合基因流动的理论模型、扩散的现场测量、种群结构的定量估计和详细的景观模型。基因流动模型将被改进和测试，以应用于许多其他物种，包括那些不容易研究的物种。

This project will produce (1) a high-resolution portrait of genetic population structure for a federally Threatened bird, the Florida Scrub Jay and (2) detailed models of how genetic material moves within and among populations via dispersal by individual jays. Two independent genetic marker systems (microsatellites and single-nucleotide polymorphisms) will be used to measure genetic similarities and differences among populations, using blood samples drawn from 3,000 individual birds across Florida and analyzed in the DNA-sequencing facilities at the Cornell Laboratory of Ornithology. Statistical models will predict the level of genetic divergence between any two populations based on their current and historic geographic relationships, and a simulation model will predict the genetic fate of a focal population following its isolation from other populations.Rapidly declining throughout its remaining range, the Florida Scrub-Jay is much-loved by the general public and a key "umbrella" species within a dwindling ecosystem. Public agencies, land managers, and conservation organizations are eager for results from this project to help select those "habitat islands" that are critical for continued dispersal and genetic health of the species. The study has unique value for basic research as well, for it will be the first to integrate theoretical models of gene flow, field measurements of dispersal, quantitative estimates of population structure, and a detailed landscape model. Gene flow models will be refined and tested for application to numerous other species, including those much less easily studied.