A raindrop hitting a mosquito in flight is like a midair collision between a human and a bus. Except that the mosquito survives.
In the study of insect flight, adaptations to complex flight conditions such as wind and rain are poorly understood. Mosquitoes thrive in areas of high humidity and rainfall, in which raindrops can weigh more than 50 times a mosquito. In this combined experi- mental and theoretical study, we here show that free-flying mosquitoes can survive the high-speed impact of falling raindrops. High-speed videography of those impacts reveals a mechanism for survival: A mosquito’s strong exoskeleton and low mass renders it impervious to falling drops. The mosquito’s low mass causes raindrops to lose little momentum upon impact and so impart cor- respondingly low forces to the mosquitoes. Our findings demonstrate that small fliers are robust to in-flight perturbations.