Mating behavior can contribute to speciation if enough physical or behavioral differences emerge between two populations such that they always choose to mate within their group. In this thesis I investigate the mating behavior of D. sechellia and D. simulans, two closely related sister species that have recently diverged. They inhabit the same geographical space, the Seychelles archipelago, yet remain separate species due to considerably low levels of hybridization. Previous studies have shown that their lack of interspecies mating is due to male mate discrimination, and that this mate choice is made by discrimination against cuticular hydrocarbon (CHC) profiles, which are unique to the two species. Chemicals uniquely present in D. sechellia's food source, Morinda citrifolia (eg L-DOPA), affects the expression levels of genes related to CHC production. Additionally, consuming M. citrifolia has been linked to changes in gut microbiomes, and the bacterial species encouraged by M. citrifolia consumption has been linked to the emergence of sexual isolation between two previously identical populations. Given the likely effects of these species' differing diets, and more specifically their consumption of L-DOPA on their CHC profiles and gut microbiome, we investigated the consequences of consuming M. citrifolia and L-DOPA on intraspecific and interspecific mating behaviors. Here we show that L-DOPA and the consumption of M. citrifolia does affect mating behavior, indicating that diet can change mating behavior and affect speciation. Our results could be indicative of complex interactions between the environment and the genetic basis of mating behaviors, and thus support motivations for more in-depth studies of the effect of L-DOPA on various genes, associated microbes, and the overall CHC profiles of D. simulans and D. sechellia.
"},{"label":"Degree","value":["Bachelor of Arts with Departmental Honors"]},{"label":"Administrative Note","value":"Drupal Node ID: 33890