July 19, 2007  Mosquito Legs' Structure Allows Amazing, Er, Feats

Mosquitoes are a summertime menace…but they’re also a marvel of mechanical engineering. They can stick to your skin, cling to a wall, and even walk on water. Now a team of physicists from China and Canada have figured out how they do it.

The trick’s in the feet. First off, mosquitoes have tiny hooks on their tootsies, which they use to latch onto skin. And they hang onto walls the same way geckos do…using hairy little foot pads that let them stick to surfaces like they’re wearing Velcro socks.

But it’s their water walking that may be their most remarkable, er, feat.  To dance across a pond…or stand atop a puddle…mosquitoes use their superhydrophobic legs. These limbs are so phenomenally water repellant…that each one could effectively support 23 times the insect’s weight. At least that’s what the physicists discovered when they took a single mosquito leg and measured the force needed to push it into a cup of water.

The reason the legs are so hydrophobic is because they’re coated with tiny, featherlike scales…that are in turn covered by even tinier ribbing.  So next time you swat a skeeter, remember: you just wacked a wonder of nature.