Evolving Eusociality: Using Drosophila to understand the evolution of reproductive constraint in worker honeybees
Eusociality is a social structure in which one female reproduces, and the others have their reproduction repressed. It is a highly successful life history strategy, allowing eusocial insects to dominate the ecosystems they inhabit. This system has evolved independently at least 20 times in insects. We have a good understanding of the theoretical reason that eusociality may evolve, but very little understanding of the mechanisms that underlie it. Are the same genes or pathways by which reproduction is repressed involved each time it arises? Or are new mechanisms evolved each time? This is the question my project has addressed.
To do so, I exposed Drosophila to the pheromone which, in the highly eusocial honeybee, queen honey bees use to prevent reproduction in their workers, queen mandibular pheromone (QMP). Theoretically, Drosophila melanogaster (fruit fly) should not have their reproduction affected, as they are not eusocial, are never exposed to QMP in nature, and diverged from honey bees ~350 million years ago. Despite this, they do show a reduction in their fecundity. As a model system, Drosophila are therefore a powerful tool to unpick the mechanism and evolution of these responses. Using multiple different approaches, my research into this response in Drosophila has allowed for the identification of mechanisms which we believe to be key to this process, in particular nutrient sensing.
Overall, the mechanisms which underpin this reproductive constraint in response to QMP are likely ancient, conserved mechanisms for responding reproductively to environmental changes. These processes appear to be co-opted during the evolution of eusociality in honey bees.
|Date||Tuesday, 28 May 2019|
|Time||12:00pm - 1:00pm|
|Event Category||Health Sciences|
|Location||Biochemistry Seminar Room 231|