Rowing Water Striders

Water strider insects are light enough that their weight can be supported by surface tension. For some time, they were thought to propel themselves by using their long middle legs to generate capillary waves–ripples– that pushed them forward, but juvenile water striders are too small for this technique to work. Instead researchers found that water striders move by using their middle legs like oars. The leg motion creates vortices about 4 mm below the water surface, and this water moving backward propels the insect forward. In the photos above, the scientists visualized the flow by sprinkling thymol blue on the water and letting the striders move freely. You can learn more about the work here or in this Science Friday episode. (Photo credits: J. Bush et al.)

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: