Dissertation Research: Phylogeography of Tympanuchus Cupido

生境破碎化和种群规模小可能导致遗传变异减少，从而影响种群的长期生存能力。新的分子遗传技术已经开发出来，可以从当代样本中确定遗传变异随时间的变化。然而，这些技术很少在已知历史和当代遗传变异模式的物种中进行测试。这项研究将检验这些技术的力量，以重建大草原鸡的遗传变异的历史模式。大草原鸡是一种松鸡，以前分布在北美中西部的大草原上，现在在分散的种群中发现，其中一些面临灭绝的威胁。遗传变异的历史模式将从在栖息地破碎化和种群下降（1872-1950）之前收集的博物馆标本的线粒体DNA序列中获得。这些将与已经分析过的来自当代人群的序列进行比较。这种对当代和历史种群的分析将为新分子技术的几个关键假设提供经验支持，并为受威胁物种减少期间的种群过程提供非常详细的图景。从保护的角度来看，这些信息对于划定管理单元和确定可能适合迁移计划的种群也是必不可少的。

Habitat fragmentation and small population size may lead to a decrease in genetic variation and, consequently, the long-term viability of populations. New molecular genetic techniques have been developed to identify changes in genetic variation over time from contemporary samples. However, these techniques have rarely been tested in species in which both historic and contemporary patterns of genetic variation are known. This research will examine the power of these techniques to reconstruct historic patterns of genetic variation in greater prairie chickens, a species of grouse that formerly occurred throughout the prairies of midwestern North America and is now found in fragmented populations, some of which are threatened with extinction. Historic patterns of genetic variation will be obtained from mitochondrial DNA sequences of museum specimens collected prior to habitat fragmentation and population decline (1872-1950). These will be compared to already analyzed sequences from contemporary populations. This analysis of both contemporary and historic populations will provide empirical support for several critical assumptions of new molecular techniques and an extraordinarily detailed picture of population processes during the decline of a threatened species. From a conservation perspective, this information will also be essential for delineating management units and identifying populations that may be suitable for translocation programs.