Bees: Biodiversity, biogeography

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Bees are essential components of almost all terrestrial environments through their pollinating activities, including many agricultural crops. Gaining an understanding of the taxonomy, ecology and evolutionary history of bees is important. We investigate these topics in a variety of ways.***1. The Atacama Desert in Chile is one of the oldest and driest deserts in the world: over large areas, rainfall is measured in mm per decade and often does not reach double digits. Even on the edge of the absolute desert there are plants and bees, and one particular genus predominates, yet most of its species remain undescribed. We will describe these species and assess the degree to which they specialize on single species of host plants (some seem to). The adaptations of bees to their floral hosts is indicated by extreme modifications of their mouthparts, with these unusual characteristics arising independently multiple times seemingly to permit access to nectar from nectaries that are deep, presumably to avoid evaporation in the arid environment.  We will compare the patterns of speciation of the bees and the plants and interpret both with dated evolutionary trees which will enable us to assess the impact of past geological events and palaeoenvironmental conditions upon the mutualisms.***2. Cuckoo bees lay eggs in the nests of other bees and might be expected to be more sensitive to a deteriorating environment because they, in effect, occupy a higher trophic level. However, they are usually taxonomically difficult. We will use integrative taxonomy on New World species of the genus Epeolus, produce identification keys for all North America species and perform morphological and molecular phylogenetic studies of the genus and its hosts and use dated phylogenies to assess the extent to which speciation of the hosts impacted that of the cuckoos. We will investigate the extent to which host chemicals are matched by the cuckoos so as to decrease the chances their activities are detected. This chemical matching would place constraints on cuckoos that switch-hosts and we will assess this with our evolutionary trees.***3. Evolutionary trees for bees based upon morphology often conflict in fundamentally important ways from those obtained from DNA sequence data. We will try to resolve this conflict by assessing the impact of taxonomic outliers (rogues).  We will also amalgamate all available morphological data for the first time - surprisingly, this has not been done previously.  We will analyse the resulting data exhaustively and combine it with molecular data.  This work is facilitated by the enormous research collection we have built up - ~30% of the world's 20,000+ species of bee and 90% of the 482 genera.  We will add data from the bee's closest wasp relatives.***Students working in my laboratory will be exposed to an enormous diversity of bee research and collaborate with experts within the department, nationally and internationally and use state.**