DISSERTATION RESEARCH The Evolutionary Ecology of Multiple Migration Strategies in a Single Species

北美一种分布广泛的蜻蜓物种表现出一种令人费解的行为：一些个体成年后会从出生的池塘进行季节性的长距离迁徙，但来自同一池塘的其他个体在成熟后仍留在附近。这种行为上的差异产生了几个问题。首先，这两种迁徙策略的相对进化利益是什么，为什么这种截然不同的行为会在一个种群中保持下去？第二，初步分析表明，这两个群体中的个体可能是密切相关的，这表明决定成年人追求哪种运动策略的机制可能是对环境触发的线索的反应。核微卫星DNA可以解决这一问题，在不同的温度和光照条件下饲养同胞幼虫可能揭示行为可塑性的基础。在迁徙的成虫翅膀中，核DNA与氢-氚和锶同位素比率的组合应该可以揭示迁徙过程中的运动规模。第三，加拿大最近的气候变化改变了移民过程。这个项目将让本科生和高中生监测朱尼尔的羽化模式。本科生将协助分子处理和操纵幼虫的发育。更广泛地说，像杜松这样的蜻蜓控制着许多昆虫、水生和陆地害虫，并帮助进行水质生物监测。

A widespread North American dragonfly species exhibits a puzzling behavior: some individuals engage in seasonal long distance migration from their natal pond as adults, but other individuals from the same pond remain in its vicinity following maturation. This difference in behavior generates several questions. First, what are the relative evolutionary benefits of the two movement strategies, and why would such contrasting behaviors be maintained in a single population? Second, preliminary analysis suggests that individuals in the two groups may be closely related, which suggests that the mechanism determining which movement strategy an adult pursues may be determined in response to an environment-triggered cue. Nuclear microsatellite DNA will resolve this issue, and raising sibling larvae exposed to different temperature and light cues may reveal the basis to the behavioral plasticity. The combination of nuclear DNA with hydrogen-deuterium and strontium isotopic ratios in migrating adult wings should reveal the scale of movement during the migration process. Third, recent climate change in Canada has altered the migration process. This project will involve undergraduate and high school students monitoring A. junius emergence patterns. Undergraduates will assist with molecular processing and manipulating larval development. More generally, dragonflies such as A. junius control many insect aquatic and terrestrial pests and assist with water quality biomonitoring.