The familiar buzz of flying mosquitoes is an important mating signal, with the fundamental frequency of the female’s flight tone signaling her presence. In the yellow fever and dengue vector Aedes aegypti, both sexes interact acoustically by shifting their flight tones to match, resulting in a courtship duet.
Surprisingly, matching is made not at the fundamental frequency of 400 Hz (female) or 600 Hz (male), but at a shared harmonic of 1200 Hz, which exceeds the previously known upper limit of hearing in mosquitoes. Physiological recordings from Johnston’s organ (the mosquito’s “ear”) reveal sensitivity up to 2000 Hz, consistent with observed courtship behavior. These findings revise widely accepted limits of acoustic behavior in mosquitoes.
This according to “Harmonic convergence in the love songs of the dengue vector mosquito” by Lauren J. Cator, et al. (Science 8 January 2009).
Above, the female Aedes aegypti; below, Mosquitos demonstrates another form of harmonic convergence.