The Geckos are the only animals that can walk upside down, belogning to the family Gekkonidae. They cling on by their special toes which has ridges, these ridges have tiny bristles and each of which end in a tiny sucker pads. Recent studies shows that the attractive forces that hold geckos to surfaces are van der Waals interactions.Every square millimeter of a gecko's footpad/sucker pads contains about 14,000 hair-like setae
