Mosquito Sexual Selection and Reproductive Control Programs

Abstract

The field of mosquito mating biology has experienced a considerable expansion in the past decade. Recent work has generated many key insights about specific aspects of mating behavior and physiology. Here, we synthesize these findings and classify swarming mosquito systems as polygynous. Male mating success is highly variable in swarms and evidence suggests that it is likely determined by both scramble competition between males and female choice. Incorporating this new understanding will improve both implementation and long-term stability of reproductive control tools.

Keywords: mating ecology; mating system; mosquito; reproductive control; sexual selection.

Figure 1.. Applications for mosquito control.

The implementation and long-term stability of many control interventions will be enhanced by filling key gaps in our understanding of mosquito mating systems. For example, many strategies rely on the mass-rearing and release of modified males (genetically [1] or chemically [3,7] sterilised, infected with a pathogen [2], or carrying a transgene [5]). Improved understanding of the degree to which male-male competition and female choice determine male mating success can inform the conditions under which these males should be maintained to maximize mating success. There are important gaps in our understanding of the variation and selection of female preferences that need to be filled in order to assess and mitigate the potential for behavioural resistance. Important evolutionary questions also remain about the relationships between traits important for male mating, male viability, and female traits that can influence vectorial capacity.

Figure 2.. Key characteristics of mosquito mating systems.

Mosquitoes are thought to be polygynous, with laboratory studies demonstrating that males can mate multiply. In polygynous systems we expect variance in male reproductive success to be high, with a small number of males achieving most of the matings. Males engage in scramble competition. Evidence of active rejection by females suggests female choice is at play in the swarm. This begs the question: what male traits do they select on, and what do they stand to gain (and risk) by choosing?