Geckos are lizards that are known for their ability to not only climb walls, but to walk nonchalantly across ceilings. Not too long ago, scientists finally found out how they do this. The toes, rather than having suction-cup type structures, have thousands of fine filaments. Being so small in diameter, these hair-like structures can fit into the smallest irregularity rather than merely hitting the high spots. This results in intimate contact with the molecules of the ceiling—snuggling so close, in fact, that the molecules of filament and ceiling attract one another almost as if parts of the same structure. Not a great force with any one filament, but multiplied by thousands, it's more than enough to defy gravity.
Now comes the finding that another group of animals has found the same
solution. Study of a jumping spider's foot indicates that when the approximately
600,000 of these fine hairs are in contact, about 170 times the weight of the spider
can be supported. Next time you see a desert spider walking up a vertical cliff, feel
free to applaud.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.