Collaborative Research: Genetic Divergence and Life History in a Plant Population

大多数植物和动物的自然种群表现出很大的遗传变异性，尽管许多因素降低了物种内的遗传多样性。动植物繁育者以及保护生物学家经常试图将遗传多样性保持在理想的品系内，因为这种多样性被认为可以减少由于近亲繁殖衰退、疾病、寄生虫和新的环境挑战而灭绝的可能性。因此，了解遗传多样性是如何在自然种群中产生和维持的，是保护生物学家的主要目标。该项目将重点研究空间异质性如何在单一植物种群内带来遗传多样性。由于坡向、积雪融化、水分蒸发或海拔高度引起的微地理差异会迫使同一地点内的植物在不同的时间开花，并可能导致早花和晚花个体受到不同的选择压力。种群遗传学理论表明，这些条件将导致保持高度的遗传多样性。在本研究系统中，融雪时间表的变化对高山植物群落施加了不同的生长和开花时间表。这种异质性的时间和空间成分如何在高山毛茅种群中保持遗传变异将被确定。这项研究将深入了解在经济上有用的动植物品种以及受威胁种群中保护遗传多样性的因素。

Most natural populations of plants and animals display great genetic variability, even though many factors reduce genetic diversity within a species. Plant and animal breeders, as well as conservation biologists, often attempt to maintain genetic diversity within desirable lines, since such diversity is thought to reduce the possibility of extinction due to inbreeding depression, disease, parasites, and new environmental challenges. Understanding how genetic diversity is engendered and maintained in natural populations is therefore a major goal of conservation biologists. This project will focus on the ways in which spatial heterogeneity can bring about genetic diversification within a single plant population. Microgeographic variation due to slope aspect, snow melt, water evaporation, or elevation can force plants within a single site to flower at different times and can lead to different selective pressures on early and late flowering individuals. Population genetics theory suggests that these conditions will lead to the maintenance of high genetic diversity. In this study system, variation in snow melt schedule imposes variable growth and flowering schedules on the alpine plant community. How the temporal and spatial components of this heterogeneity maintain genetic variation within an alpine population of Ranunculus will be determined. This research will produce insight into factors that preserve genetic diversity in economically useful plant and animal breeds as well as in threatened populations.