A gecko can stick to almost any surface because of the superbly crafted structure of its soles—very fine hairs have tips that are even more finely divided. (See Great gecko glue? Creation 23(1):54–55, 2000). Ingenious scientists have copied this structure to make a powerful adhesive (Gecko foot design—could it lead to a real ‘spiderman’? Creation 26(1):22–23, 2003). Somehow this adhesive manages to stay clean, unlike sticky tape, which soon picks up dirt and becomes useless.
Gecko foot researchers have now shown how. They coated the gecko feet with dirt, yet it sloughed off completely within five steps on a clean surface. It’s all to do with the geometry of the fine hairs. The dirt particles are too small to be in contact with enough hairs to overcome the attraction to any surface. So the hairs, in effect, repel the particles towards the surface.
Lead researcher Dr Kellar Autumn ‘is convinced the possibilities are infinite. Imagine bandages that leave no residue. Gecko-inspired climbing equipment. Cellular phones that never shatter.’
- Proceedings of the National Academy of Sciences, 11 January 2005, pp. 385–389.
- New York Times, www.nytimes.com, 4 January 2005.
Surely the gecko’s foot needed a Designer!