Dissertation Research: Testing how traits shape individual resource use in response to competition: implications for ecosystem functioning

许多植物依靠昆虫授粉，包括人类食用的大多数水果和蔬菜。然而，要使一朵花受精，花粉通常必须来自同一种植物。因此，昆虫传粉者的一个关键属性是它们的保真度，即它们将花粉从一朵花带到同一物种的另一朵花的可能性有多大。蜜蜂作为传粉者特别受重视的一个原因是它们的高保真度，但最近的研究表明，蜜蜂的保真度可能会有所不同。这个项目将测试哪些特定因素提高或降低蜜蜂的保真度。除了增加对重要生态系统服务的科学认识外，该项目还将为博士论文增加一个新的组成部分，并为两名本科生提供密集的实地研究经验。为了向公众传达结果，研究人员将在亚利桑那州图森的沙漠博物馆帮助建立一个关于传粉媒介重要性的推广计划。先前在科罗拉多州落基山脉草地上对大黄蜂授粉的研究表明，大黄蜂之间对鲜花的竞争提高了忠诚度。然而，这取决于一个物种的平均舌头长度：当其他物种的大黄蜂被移除时，舌头较短的物种往往会失去更多的保真度，植物繁殖也会减少更多。这个项目将测试一个物种内个体之间的变异是否有同样的效果。研究人员将把草地上除一种大黄蜂外的所有大黄蜂都移走，并跟踪它们的飞行，测量单个蜜蜂的舌头长度。研究结果将促进对传粉保真度生态学的认识。更广泛地说，研究将显示个体动物之间的差异如何导致它们对竞争做出不同的反应，从而对生态系统功能产生影响。

Many species of plants depend on insects for pollination, including most of the fruits and vegetables that humans eat. However, for pollen to fertilize a flower, it must generally come from the same species of plant. A critical attribute of insect pollinators is thus their fidelity, how likely they are to carry pollen from one flower to another flower of the same species. One reason that bees are especially valued as pollinators is their high fidelity, but recent research has shown that the fidelity of bees can vary. This project will test which specific factors enhance or diminish fidelity in bees. Besides increasing scientific understanding of an important ecosystem service, the project will add a new component to a doctoral dissertation and provide intensive field research experience for two undergraduate students. To communicate results to the general public, researchers will help create an outreach program on the importance of pollinators at the Desert Museum in Tucson, Arizona.Previous work on pollination by bumblebees in meadows in the Rocky Mountains of Colorado shows that competition between bumblebees for flowers promotes fidelity. However, this depends on the mean length of the tongue of a species: when other species of bumblebees are removed, shorter tongued species tend to lose fidelity more and plant reproduction decreases more. This project will test whether variation between individuals within a species has the same effect. Researchers will remove all but one species of bumblebee from areas in meadows and follow the flights and measure the tongue lengths of individual bees. Results will advance knowledge of the ecology of fidelity in pollination. More broadly, research will show how differences between individual animals cause them to respond differently to competition, with consequences for ecosystem function.