Low-frequency sounds elicit escape climb in free-flying Aedes aegypti mosquitos

Mosquitoes use their sensitive hearing in a well-described courtship and mating behavior, but their ability to discriminate other stimuli relevant to their survival and reproduction via this sensory channel remains underexplored. Here, we characterize a rapid climb response in free-flying mosquitoes elicited by loud low-frequency sounds (tested at 180Hz and 300Hz) but not by tones of equivalent acoustic loudness reflecting conspecific female (450Hz) and male (700Hz) wingbeat frequencies. Presentation of the same sounds in tethered flight elicited modulation of both wingstroke amplitude and frequency components similar in magnitude to those observed in response to a looming visual stimulus. These tones are spectrally consistent with recorded audio of a dragonfly takeoff, playback of which is sufficient to release the behavior. Taken together, these data are consistent with the hypothesis that mosquitoes use their hearing to detect the acoustic signature of aerial predators such as dragonflies.