Dissertation Research: Phylogeny of Orchid Bees (Hymenoptera: Euglossini), the Evolutionary Significance of Fragrance Gathering, and Patterns of Orchid Host Use.

了解传粉系统对于研究昆虫和植物共同进化的生物学家以及对传粉者为作物施肥所提供的生态服务感兴趣的农业学家来说至关重要。一个共同进化的传粉系统的经典例子是兰花和桉花蜂之间的相互作用。Euglossini由大约200种金属色的快速飞行昆虫组成，它们栖息在中美洲和南美洲的热带雨林中。它们的共同名称“兰花蜂”源于雄蜂作为数百种兰花的传粉者的密切联系。雄性在专门的腿口袋里收集和储存兰花的香味，然后在求偶期间用这些来引诱雌性。在收集香味的同时，雄性蜜蜂通过一种奇妙的机制使花朵受精。兰花与大多数开花植物不同，它不产生松散的花粉粒，而是将花粉包裹在一个紧密的团块中，称为授粉体。根据兰花的种类，花粉的底部有一个粘性的表面，附着在蜜蜂身体的不同部位。雄蜂把花粉从一朵花带到另一朵花，把花粉粘在身体上合适的位置，使每个物种受精。本研究将通过绘制伴侣双方的地理分布，分析DNA序列以重建其进化树，以及描述雄性蜜蜂收集的化学气味以了解这些化学气味如何被用作特定的交配信号来研究这些蜜蜂及其相关兰花的进化。这项研究将阐明蜜蜂的进化如何影响兰花的进化，反之亦然。它还将展示罕见的收集香味的行为如何影响不同种类蜜蜂的进化。更广泛地说，它将调查这样的系统是否可以共同进化，影响彼此的轨迹，刺激生物多样性的起源。在这种系统中，紧密的共生关系将物种群体联系在一起。通过使用多种方法，本研究将连接传统上分离的科学领域，如化学生态学和分子系统学。这些结果将有助于我们理解作为授粉生物学基础的互惠相互作用的进化，这是大多数农业系统中至关重要的领域。一名研究生和几名本科生将接受昆虫学、分子系统发育学和行为生态学的培训。兰花蜂分布在整个中美洲和南美洲，这里描述的实地调查和实验室合作将促进更大的国际交流。研究结果将产生不同的分子、化学和行为数据集，这些数据集将通过开放的网络资源提供给未来的研究人员和教育工作者。最后，这项研究将有助于实现更广泛的目标，即了解自然世界及其保护。

Understanding pollination systems is of central importance to biologists investigating the coevolution between insects and plants, and agriculturalists interested in ecological services provided by pollinators that fertilize their crops. A classic example of a coevolved pollination system is the interaction between orchids and euglossine bees. The tribe Euglossini comprises ~200 species of metallic-colored, fast flying insects that inhabit the rainforests of tropical Central and South America. Their common name, 'orchid bee,' derives from the close association that the male bees have as pollinators of hundreds of species of orchids. The males collect and store fragrances from orchids in specialized leg pockets, and they later use these to seduce females during courtship. While collecting fragrances, male bees fertilize flowers by a fascinating mechanism. Orchids, unlike most flowering plants, do not produce loose pollen grains, but instead package their pollen in a compact mass called a pollinium (pl. pollinia). The pollinium has a sticky surface at its base that adheres to different parts of the bee's body, depending on the species of orchid. A male bee carries pollinia from one flower to another, fertilizing each species with pollinia stuck to the appropriately matched location on its body. This research will investigate the evolution of these bees and their associated orchids by mapping the geographic distributions of both partners, analyzing DNA sequences to reconstruct their evolutionary trees, and characterizing chemical scents collected by male bees to understand how these are used as specific mating signals. The study will elucidate how the evolution of the bees affected the evolution of the orchids, and vice versa. It will also show how the rare behavior of fragrance gathering affected the evolution of different species of bees. More broadly, it will investigate whether systems like this, in which tight mutualisms bond groups of species together, can coevolve, affecting each other's trajectories and spurring the origin of biological diversity.By using multiple approaches, this study will bridge traditionally separate scientific fields such as chemical ecology and molecular systematics. The results will contribute to our understanding of the evolution of mutualistic interactions that are the basis of pollination biology, a field of critical importance in most agricultural systems. One graduate student and several undergraduates will receive training in entomology, molecular phylogenetics, and behavioral ecology. Orchid bees are distributed throughout Central and South America, and the fieldwork and laboratory collaborations described here will foster greater international communication. The results will generate diverse molecular, chemical and behavioral datasets that will be made available to future researchers and educators via open-access web-based resources. Finally, the research will contribute toward the broader goal of understanding of the natural world and its conservation.