The effect of village structure, trait divergence and GM release regimes on the coexistence of Ae. aegypti and Ae. albopictus

Through the diseases they carry, Ae. aegypti and Ae. albopictus have substantial burdens on global public health. Despite originating on different continents, there are regions where these two species overlap in spatial distribution, which can result in competitive exclusion, or coexistence. A mechanism regulating these coexistence patterns is reproductive interference (also called satyrisation), which is where incomplete species recognition results in heterospecifics engaging in mating activities which do not produce viable offspring and cause a fitness cost to one/ both of the species involved. In my rotation project, we developed a theoretical framework (based on modified Lotka-Volterra equations) to investigate the interaction between GM Ae. aegypti releases and the impact of reproductive interference between Ae. aegypti and Ae. albopictus populations on patterns of coexistence and exclusion. However, this model is non-spatial and thus most appropriate where the species populations are mixed and dispersed over an homogeneous space, which is not true of Ae. aegypti and Ae. albopictus populations. Thus, my initial project will be a spatially explicit extension of my rotation project, but omitting the release of GM Ae. aegypti. I plan to form a network model to examine how the structure of houses in a village impacts coexistence between Ae. aegypti and Ae. albopictus. I will then conduct fieldwork to determine whether Ae. aegypti and Ae. albopictus diverge in their peak biting times to reduce the fitness cost associated with reproductive interference. The final section of my thesis will expand the initial theoretical model to include different spatial release regimes of self-limiting GM Ae. aegypti. Thus, my thesis will extend our knowledge of the ecology of coexistence between Ae. aegypti and Ae. albopictus, and will be relevant to policy decisions on Aedes control measures.