Stanford University researchers turned to the gecko to inspire their wall-crawling technology.

The researchers, working with the US Defense Advanced Research Projects Agency, took inspiration from the toes of geckos to create the pads that allowed a 69.8-kilogram man to scale a 3.5-meter glass wall.

The team, writing in the Journal of the Royal Society Interface, said "microwedges" in the silicone pads generate electrostatic Van der Waals forces that cause molecules to be attracted to each other.

"The synthetic adhesion ... [improves] upon the adhesive-bearing structures of a gecko's toe and [enables] a human to climb vertical glass using an area of adhesive no larger than the area of a human hand," the researchers wrote.