Thursday, 1 November 2012

Row, Row, Row your Leg: The Secret behind Water Strider's Movement in Water

Water striders are an insect people describe as an animal that harnesses the physical properties of surface tension for its mobility.  You would think that after several years of studying water striders an insect no larger than a quarter you would have figured them out.  There is still a lot to learn apparently.  

Nobody really understood how they push forward to move.  People thought that capillary waves were used to move.  A MIT math major and high speed cameras helped to solve the puzzle (loving high speed cameras in science from hummingbirds to water striders they are more useful than ever before).  Hu (MIT math guy) along with his PhD supervisor John Bush found that the water striders only use the middle of their three pairs of legs to "row" across the water.  The ouring leg creates a vortice just underneath the surface that twist away from the standing legs which due to surface tension are luckily on top of the water.