Demography and Fragmentation in an Avian Species: A Genetic Analysis

这个项目调查了遗传的后果， 一个极端的生态专家在一个罕见的和正在消失的栖息地。 佛罗里达灌丛松鸦是一种受联邦政府威胁的鸟类， 仅限于一个正在迅速被人类消灭的栖息地。 22年来对一个显著群体的详细研究表明， 表明这些松鸦有一个不寻常的社会系统， 从他们出生的地方迁移了不止几个领土。 这种非常有限的扩散可能导致 短距离的遗传变化，特别是在栖息地内 这是高度分散的。 各种复杂的基因 技术（DNA“指纹”和测序）将用于 研究地方和区域尺度上的遗传变异。 具体目标是：1）确认生殖发生 仅通过每个区域上的配对（即，额外配对或 域外受精是罕见的或不存在）; 2）测试 近亲繁殖的水平是否影响终生生殖 3）比较距离、 栖息地隔离和种群大小对遗传变异的影响， 分化，以及4）测试这些遗传效应是否匹配 这是长期人口统计数据预测的。 除了其 理论应用，本研究将进一步保护 通过展示栖息地的丧失和破碎化 影响了生态上特殊物种的基因组成。

This project investigates the genetic consequences of being an extreme ecological specialist in a rare and vanishing habitat. The Florida Scrub Jay is a federally Threatened bird species, restricted to a habitat that is rapidly being eliminated by man. Twenty-two years of detailed study of a marked population have shown that these jays have an unusual social system, and rarely move more than a few territories from where they were hatched. This very limited dispersal may result in rapid development of genetic changes over short distances, especially within a habitat that is highly fragmented. A variety of sophisticated genetic techniques (DNA 'fingerprinting' and sequencing) will be used to examine genetic variation at both local and regional scales. Specific goals are to: 1) confirm that reproduction takes place only by the mated pair on each territory (i.e., extra-pair or extra-territorial fertilizations are rare or absent); 2) test whether levels of inbreeding affect lifetime reproductive performance; 3) compare the effects of distance, degree of habitat isolation, and population size on genetic variation and differentiation, and 4) test whether these genetic effects match those predicted by long-term demographic data. Besides its theoretical applications, this study will further the protection of biodiversity by showing how habitat loss and fragmentation affect the genetic makeup of ecologically specialized species.