Copying the Gecko’s Feet

Land animals also have much to teach. For example, the small lizard known as a gecko has the ability to climb walls and cling upside down on ceilings. Even in Bible times, this creature was known for this amazing capability. (Proverbs 30:28) What is the secret of the gecko’s ability to defy gravity?

The gecko’s ability to stick even to glass-smooth surfaces comes from the tiny hairlike structures, called setae, that cover its feet. The feet do not exude glue. Rather, they exploit a minute molecular force. The molecules on the two surfaces bond to one another because of very weak attractive forces known as van der Waals forces. Normally, gravity easily overpowers these forces, which is why you cannot climb a wall simply by placing your hands flat against it. However, the gecko’s tiny setae increase the surface area in contact with the wall. Van der Waals forces, when multiplied across the thousands of setae on the gecko’s feet, produce enough attraction to hold the tiny lizard’s weight.

What use may this discovery have? Synthetic materials made to imitate the gecko’s feet could be used as an alternative to Velcro​—another idea borrowed from nature.a The journal The Economist quotes one researcher as saying that a material made from “gecko tape” could be particularly useful “in medical applications where chemical adhesives cannot be used.”

A gecko’s feet don’t get dirty, never leave a residue, stick to any surface except Teflon, and attach and detach with little effort. Researchers are trying to copy them