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

一种分布广泛的北美蜻蜓表现出一种令人费解的行为：一些个体在成年时从它们的出生池塘进行季节性的长途迁徙，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益处是什么？为什么这种截然不同的行为会在单一种群中保持？第二，初步分析表明，这两组个体可能密切相关，这表明决定成年人采取何种运动策略的机制可能是由环境触发的线索决定的。核微卫星DNA将解决这一问题，而饲养暴露于不同温度和光照条件下的同胞幼虫可能会揭示行为可塑性的基础。将核DNA与迁徙成虫翅膀的氢、氘和锶同位素比值相结合，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。该项目将涉及本科生和高中生监测朱鹭的出现模式。本科生将协助分子处理和操纵幼虫的发育。更普遍的是，像刺桐这样的蜻蜓控制了许多水生和陆生害虫，并协助水质生物监测。

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.