How geckos keep firm grip to climb walls

Zee Media Bureau

New Delhi: For years, biologists have been astonished by the power of gecko feet. Ever wondered how do they get their impressive sticking ability? Geckos are equally at home on vertical, slanted, even backward-tilting surfaces. Researchers at Oregon State University (OSU) have identified the adhesive system with which geckos run up and down with such effortless grace. The toes of geckos use tiny, branched hairs called "seta" that can instantly turn their stickiness on and off, and even "unstick" their feet without using any energy, the findings showed. These extraordinary hairs contribute to the ability of geckos to run, evade predators, and protect its very life and survival. In essence, a gecko never has a bad hair day. Even more compelling is the minimal amount of energy expended in the whole process, as a gecko can race across a ceiling with millions of little hairy contact points on its feet turning sticky and non-sticky in a precisely integrated process. This "smart" adhesion system allows them to run at 20 body-lengths per second, and hanging from a ceiling, the forces provided by the seta could actually support 50 times the body weight of the gecko. Geckos` feet are by default non-sticky but the stickiness can be activated by a small sheer force to produce this surprisingly tough form of adhesion. The study appeared in the Journal of Applied Physics. (With Agency inputs)