Polyandry as a Signal of Phase Shift in Female Desert Locust Schistocerca gregaria

Abstract

The multiple mating by female (polyandry) is a widespread behavior in insect species. This behavior is known to be a kind of itness maximization, but some case of sexual selection factors can explain the evolution of this behavior in relation with the phenotype plasticity model. In this paper, we analyze the role of polyandry in the reproductive success and in the phase shift process in the gregarious desert locust. In an applied perspective, knowledge on the reproductive success and in the phase shift process is essential to perform mass rearing for human food production. Our results suggest that multiple mating is not associated with itness beneits. Polyandry acts as a signal of phase shift through ofspring. We showed that hatchlings of gregarious females mated only once are smaller and green at 87.2% in irst egg pods and produced the solitary form of the desert locust. The coloration of ofspring in females mated with two males reaches only 15.2% of green forms versus 84.8% of mostly blacks. In this study, we showed that females mated more than two times with diferent males produce larger eggs, heavier, and black hatchlings characteristic of gregarious phase known in S. gregaria.