music; ambience party favor horn
BF: â€œWe discovered that geckos run up walls using bizarre toes. Their toes have millions of tiny little hairs, and these hairs have the worst case of split ends possible.â€
Who knew split ends could be so useful? Iâ€™m Jim Metzner, and this is the Pulse of the Planet. Bob Full is a Professor of Biology at UC Berkeley, and heâ€™s collaborating with engineers to develop materials that replicate the unique adhesive characteristics of gecko feet. And itâ€™s the structure of each individual hair on a geckoâ€™s foot that gives it its unique properties.
BF: â€œThey have about 100 to 1,000 split ends. And they donâ€™t stick by suction or by any kind of glue. Whatâ€™s phenomenal is that those branches are so small these little split ends that they stick by intermolecular forces, just the forces that hold molecules together.â€
Remarkable, too, is the speed and method by which those individual hairs release from a surface. Bob Full uses transparent gecko-sized treadmills and high-speed videos to analyze the geckoâ€™s movements.
BF: â€œThey have their toes peel away from the surface, very much like a party favor, you know the thing you put in your mouth and you blow, and it uncurls, and then, you let it go, and it curls back?â€
[party favor horn]
BF: â€œThe geckos do that with their toes. If you look at a toe, you can see it uncurl to grab onto the surface and then peel away from the surface so that it can unstick. They can attach and detach really rapidly. They can run up a wall; in thousandths of a second, they can attach and detach these little toes.â€
Gecko adhesion might lead to revolutionary new products and designs that could help our everyday lives. Weâ€™ll hear more in future programs.
Bob Full is one of the participants in the Kidsâ€™ Science Challenge, our nationwide competition for third to sixth graders, made possible by the National Science Foundation. Check out KidScienceChallenge.com.