Flower visitation on two wings: the impact of Diptera as pollinators

点击翻译按钮获取中文摘要

Flies (Diptera) are among the most diverse groups of animals on the planet, with over 160,000 described species. In particular, flower flies (Syrphidae) have been recognized in recent years for their important role in pollination. Visiting over 50% of global crop plants, their economic value has been estimated at $300 billion USD per year, and they have also been recorded visiting over 70% of animal-pollinated wildflower species in Europe. Syrphidae is a large family of flies, with about 6,300 species described worldwide, and just over 800 species known to occur in continental North America. The group's diversification is relatively well understood at the sub-familial level, thanks to several recent publications, but important questions remain-especially concerning the subfamily Eristalinae, a group widely understood as a collection of unrelated lineages. My research program has three long-term goals: 1) To understand the evolution and diversity of flower flies worldwide through phylogenetic analyses and taxonomic revisions; 2) To facilitate access to flower fly species concepts for other researchers through the publication of user-friendly identification tools; 3) To determine the impact of fly, especially flower fly, pollination in natural and agricultural ecosystems. My research team will work toward these goals over the next five years through a focus on the diversity, evolution, and ecology of North American flower flies. Our understanding of North American flower flies has several major limitations, hindering our ability to use these groups in ecological studies. There is also a critical need to understand our North American flower fly diversity in order to map the plant-pollinator relationships that underpin vulnerable and rapidly changing habitats such as the Arctic. To meet these pressing needs, my short-term objectives are: 1) Trace the evolution of the flower fly tribe Rhingiini using phylogenomic methods, then use this knowledge to recognize monophyletic groups of species; 2) Guided by the monophyletic groups delimited by Objective 1, investigate the taxonomy of the species-rich flower fly genus Cheilosia to improve species concepts; and 3) Map plant-pollinator networks of flowers and flies in the Canadian Arctic through pollen metabarcoding, with a focus on species of Cheilosia. The current lack of taxonomic clarity regarding species-rich genera such as Cheilosia greatly limits our ability to study the pollination dynamics of flower flies in North America. Given that flies are the dominant pollinator in cold-weather environments such as the Canadian Arctic, it behooves us to uncover the taxonomy and specific ecological services contributed by these insects. Specific knowledge of Arctic pollination networks will provide a better understanding of keystone plant and insect species. Bolstered by this knowledge, we will be better able to predict how these ecosystems will be altered or disrupted by the increasingly warm climate.