A Cacophony or a Chorus?: The role of sound in the coordination of mosquito mating swarms

Mosquito-borne diseases such as dengue, yellow-fever virus and malaria are believed to impact one third of the global population (World Health Organisation, 2014). To reduce the global health burden caused by mosquito-borne diseases, population control measures need to be implemented. Current methods use insecticides, however the growing threat of insecticide resistance poses a significant challenge. New strategies of control focus on mosquito reproductive processes, involving the release of laboratory reared males to compete with wild males for mates. For effective implementation, a thorough understanding of mosquito mating systems and mating success is required.

Mosquitos mate in aerial swarms which are often thought of as lek-formations. Swarms are initiated by and primarily composed of males, with females joining in smaller numbers thereafter. The dynamics of swarming behaviour are not currently well understood. In Anopheline mosquitos, swarms seemingly appear to move randomly around a focal point, however contain periods of parallel flight possibly mediated by velocity matching (Shishika et al., 2014). More recently, the role of acoustic signalling has been implicated as a possible mediator for swarm dynamics (Aldersley et al., 2017). Male mosquitoes have been shown to find potential female mates in swarms through the sound of their wing beats, and are believed to communicate with other males through similar acoustic mechanisms. The degree to which these observed behaviours are due to individual interactions within the swarm, or a method of coordinating swarm dynamics remains unclear.

This project will focus on the acoustic interactions of swarming Yellow-Fever mosquitoes, Aedes aegypti, which is an important arbovirus vector. Using a combination of experimental manipulation and simulations, we aim to determine the role of acoustic interactions in the dynamics of swarming mosquitos. As a key part of the project we will develop novel methods for delivering playbacks to swarming individuals. Throughout, we will develop tools to track free-flying mosquito movements and the acoustic emissions they produce to determine the importance of acoustics in swarming dynamics. We will test both evolutionary and mechanistic hypotheses that may explain why these aggregations form, and better understand the role of acoustics in mosquito swarm dynamics.


References:

Aldersley et al. 2017. Emergent acoustic order in arrays of mosquitoes. Current Biology. 27 (22): R1208-1210.

Shishika et al. 2014. Male motion coordination in anopheline mating swarms. Scientific Reports. 4: 6318.

World Health Organization 2014. A global brief on vector-borne diseases.