Thesis Defense at CES on 27 February 2018 at 10:00 am titled "On trait evolution in a heterogeneous environment: Oviposition site selection in a mosquito in response to multiple risk factors" by Manvi Sharma from CES
An important area of interest in behavioural ecology is to understand the large diversity in traits related to reproduction and one explanation is that this diversity is adaptive and is shaped by natural selection. In wild populations, multiple selection pressures are likely to shape trait evolution. While these multiple selection pressures can manifest through different ecological or demographic conditions, these conditions themselves could vary predictably over space or time, or in an unpredictable manner, a relatively less studied form of environmental variability.
In my thesis, I attempt to understand how oviposition site selection, a behaviour where multiple selection pressure regimes are rarely considered, is shaped by multiple factors in a variable environment. Using Aedes aegypti and Ae. vexans as model systems, I first measured fitness trade-offs associated with larval predation risk and conspecific competition risk at potential oviposition sites through experimental manipulation in the laboratory. I also quantified spatial and temporal variation in two risk factors, pool desiccation risk and larval predation risk, through an observational study under natural conditions. Considering these trade-offs, I predicted and tested female oviposition site selection response to these varying multiple risk factors in the field. My findings indicate that oviposition site selection responses are complex, sensitive to interactions between multiple risk factors and influenced by patterns in variability in some of these factors.