Northwest Arkansas Democrat-Gazette
Rain no flight hazard for skeeters
A single raindrop can weigh 50 times as much as a mosquito. So how can the insects fly through a downpour and come out alive?
A new study reports that the answer lies in the mosquito’s low mass and its strong exoskeleton.
The researchers observed mosquitoes by using high-speed video and discovered that most of the time they do not resist the impact of a water drop and instead “go with the flow,” in the words of one author, David L. Hu, a mechanical engineer and biologist at the Georgia Institute of Technology.
“It’s kind of like boxing with a balloon,” he explained. “There’s no way to pop the balloon because it doesn’t resist you at all.”
About 25 percent of the time, raindrops fall directly between a mosquito’s wings. In these cases, the mosquito is absorbed into the falling water drop, but it pulls away just before the drop hits the ground.
The insect’s long wings and legs make it “like a kite with long tails, and it can pull away,” Hu said.
Also, according to supplemental information
published with the article in The Proceedings of the National Academy of Sciences, hairs that cover the insects’ wings help them to shed water, so glancing blows slide off easily.
The researchers say the mosquitoes’ resilience can serve as a model in efforts to develop robotic airborne search-and-rescue vehicles. The smaller the robot, Hu said, the more robust it will be.
“If you make it very, very small, you basically don’t have to do anything else to make it survive,” he said.
Video explaining the research is available online at cos.gatech.edu.