Tree frogs’ feet may hold some very sticky promise
Long neglected in favor of legs, frogs’ feet are getting fresh attention for their adhesive properties that could someday have medical applications.
Tree frogs, such as the tiny White’s tree frog, have sticky pads on their feet that they use to grab onto tree branches and leaves and other surfaces in their native habitat. Scientists have discovered that these feet pads have the ability to repel dirt as well. Now, they are studying the design of the frogs’ feet with the hopes of applying the technology to products such as medical bandages and reusable adhesives.
To make their feet sticky, the tree frogs secrete mucus. They then can boost stickiness by moving their feet against a surface to create friction, researcher Niall Crawford at the University of Glasgow in Scotland found.
The design of the feet themselves is important. Tiny hexagonal patterns on the White tree frog’s pads help it cling to a surface and create friction, while also making space in between for the mucus to spread evenly. The mucus makes the pad sticky and carries away dirt.
Frogs whose feet were contaminated with dust lost their grip during the experiment, but simply “taking a step enables frogs to clean their feet and restore their adhesion ability,” Crawford said. The findings were presented at the Society for Experimental Biology annual conference in Glasgow.
Tiny tree frogs may hold some secrets to improving bandages.