Evolution of generalist pollination systems

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Different species can adopt very different strategies to use the resources in their environments. Ecological specialists use a narrow range of resources whereas generalists use a broad range. These differences can have important implications for the stability of ecosystems as generalists are more robust to environmental changes. Indeed, it is easy to conceive that a plant relying on a single species of pollinator for its reproduction will be more vulnerable than a species that can be pollinated by many species.******Historically, the attention of pollination biologists has been mostly directed towards the study of specialization systems, perhaps because they are more spectacular. One classic example is Darwin's Angraecum sesquipedale orchid and its predicted (and eventually confirmed) long proboscis pollinating moth. Yet, more and more researchers are calling for further studies on generalist systems as these are abundant and have been important in plant evolution.******This proposal addresses specifically the mechanisms and consequences of generalist pollination strategies in a plant group from the Caribbean Islands from the Gesneriaceae family. I propose three short-term objectives.******In the first objective, I will determine the processes that gave rise to generalist strategies. Specifically, I will test if the evolutionary success of generalists is due to the fact that they have evolved trait innovations that allows them to be successfully pollinated by different pollinators. This will consist in studying pollinator effectiveness, but also the floral shape variance in populations of species with contrasting pollination strategies.******In the second objective, I will test if the molecular mechanisms involved in the independent evolution of convergent morphological traits associated with generalist strategies involved the same genes or genome regions. This will involve comparative QTL mapping of generalists of different origins as well as comparative transcriptomic studies.******Finally, the third objective will address the significance of generalist systems. It will test if generalists have higher diversification rates than specialists using phylogenetic approaches, and if the presence of species on oceanic islands affect these rates. ******This proposal has the potential to drastically change the way we perceive ecological generalist strategies by showing how they evolve and by quantifying their evolutionary success.