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Audio file of the house gecko: By Glueball (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
Of the eight gecko species here in Hawaii, the house gecko, Hemidactylus frenatus, is probably the one you are most familiar with. We've all seen their gravity defying jaunts across the ceiling or watched them chasing down cockroaches and moths. Yet we may not realize just how remarkable these lizards are. For starters, they can vocalize, chirping out the familiar tuk-tuk-tuk-tuk-tuk at night, and yet vocalizations are unusual for members of the Order Squamata, the group that includes all lizards and snakes. Secondly, they'll kill it in a staring contest as their eyelids are fixed; no blinking for this guy. Instead, they clean their eyes with their tongues. Their eyes are quite beautiful, with a vertical pupil that resembles a keyhole. They are also capable of caudal autotomy, the ability to lose part of their tail, as a defense mechanism. The severed appendage will continue to wriggle, further confusing the would-be predator.
And if that's not enough, consider their extraordinary toe pads. They are covered with small hairs called setae, which are mere micrometers in diameter and spatula-shaped at their ends. This allows for a great deal of surface area contact, and generates van der Waals forces, the same forces you learned about in Chemistry class that contribute to molecular bonding. This is what allows the gecko to do its spider-man thing. Scientists around the world are working on creating a synthetic version of the gecko toe pad. "Gecko tape," as it is often referred to, is still in its early phase of development, but could one day be used to hang televisions on walls, create fumble-free football gloves, or replace sutures in surgery. Others envision it on the boots of astronauts, enabling them to walk on the space craft unencumbered by harnesses. That little friend hanging around your porch light could one day have us literally climbing the walls.
welcomes you to visit with the all the wonderful flora and fauna that we share this lovely aina with.