Mosquitoes may not seem divine, but they can walk on water, thanks to their ultraflexible legs. A mosquito’s leg is made up of three sections, known as a femur, a tibia, and a tarsus. The tarsus is the long, thin section that skims the water’s surface, pictured above. It is covered in scales that repel water molecules, but that only partly explains how mosquitoes stay afloat, a new study shows. To better understand how tarsi support mosquitoes’ weight, researchers plucked the leg fragments from mosquitoes and measured the force they exerted when pressed against water. The secret of the tarsus is its flexibility, they found—stiff tarsi exert less force before breaking through the water’s surface. A flexible tarsus, in contrast, can support up to 20 times the weight of a mosquito by conforming to the water’s surface, the researchers report online today in AIP Advances. Mosquitoes can adjust the level of support by changing the angle at which tarsi impact the water, allowing them to walk, take off, and land in gusty weather. Understanding the science of mosquito legs could be useful for the development of miniature water-striding robots, researchers say. Presumably, these robot mosquitoes would be less annoying than the real kind.
admin December 3, 2019 rcnilkgo