Geckos use toe hairs to turn stickiness on/off

If you've ever spent any time watching a gecko, you may have wondered about their uncanny ability to adhere to any surface -- including upside down on ceilings. It turns out the little lizards can turn the "stickiness" of toe hairs on the bottom of their feet on and off, which enables them to run at great speeds or even cling to ceilings without expending much energy.