By Peter Weiss
Lizard, lizard on the wall, why is it you do not fall?
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2003/02/2430.jpg?resize=150%2C150&ssl=1)
Scientists have been asking that question of the limber little gecko for at least 75 years. These scaly climbers can scuttle nimbly across a polished glass ceiling. In a pinch, they can hang by one toe.
Over the decades, experiments and observations have ruled out suction, electrostatic forces, and glue as possible explanations. Now, a West Coast team of scientists and engineers has discovered that a surprisingly large sticking force arises when tiny hairs, or setae, on gecko feet rub up against surfaces.