Decades-old explanation for the lizards’ supersticky feet is wrong, researchers say
Clinging upside down to polished surfaces is simple for geckos, but scientists’ grasp of the underlying forces behind this phenomenal adherence just became murkier. Researchers report that the adhesiveness of gecko feet is aided by static electricity, contrary to long-held beliefs.
The misconception over gecko adhesion dates back to 1934, says Yale University chemical engineer and study coauthor Hadi Izadi. A German scientist named W.D. Dellit wondered whether gecko adhesion was explainable by electrostatic forces, the differences in electric charge that build up between any two surfaces. Dellit used X-rays on the air surrounding the reptile’s toes as they stuck to a metal wall. The X-rays ionized the air, neutralizing any charge on the wall’s surface, Izadi explains.
Anything attached to the wall via electrostatic forces should have fallen, yet the lizards remained. So researchers ruled out electrostatic forces and moved on to other ideas. Over a