•  
  •  
 

EFFECT OF VIRGIN FEMALES ON MALE COMPETITION UNDER REINFORCEMENT IN THE DROSOPHILA SUBQUINARIA-RECENS SPECIES COMPLEX**

Abstract

A main foundation revolving around evolutionary genetics is the intricate process of speciation. Speciation constitutes continuous evolutionary change into new and independent lineages, driving evolution and illustrating the orientation of the ecosystem. The classic mechanism involves genetic differentiation due to geographically isolated populations, reducing hybrid fitness during secondary contact. For example, the mushroom-feeding Drosophila subquinaria complex was separated into western and eastern lineages during the Wisconsin glaciation. As a result, selection fixed a Wolbachia endosymbiont in Drosophilia recens, which induced a strong postzygotic barrier. Thus, the populations’ divergence was reinforced because of hybrid inviability and selection on prezygotic Drosophilia subquinaria female mate discrimination. Interestingly, the reinforcement is so strong that female mate choice regarding D. subquinaria also discriminated against different geographically located D. subquinaria populations, fostering cascade reinforcement. While female mate choice in this system is well studied, the role of males remains largely unexplored. Understanding male behavior promotes inferences in population dynamics and has direct influences on fitness. In this case, we investigate the root of male behavior in D. subquinaria and D. recens. Although female dynamics within species’ mate choice are well studied, the extent of male behaviors is unknown. In this study, we assay male aggression in 30 different conspecific competition trials per species to elucidate patterns of male behavior in the presence of virgin females. We hypothesize that D. recens males are going to show increased levels of aggression due to reduced mating opportunity when influenced by D. subquinaria prezygotic mate discrimination.

Acknowledgements

Piedmont University Natural Science Department

This document is currently not available here.

Share

COinS