Chameleon Tongues Are Amongst World's Fastest, Most Powerful

rosette-nosed-chameleon .05Jan2015
The rosette-nosed chameleon (Rhampholeon spinosus) can accelerate its tongue at a rate of 1.6 miles per seconds squared, the fastest bodily movement of any reptile, bird or mammal. Christopher Anderson

Chameleons can famously blend into a variety of different backgrounds, appearing as fresh moss in one setting or a bumpy twig in another. But they possess another incredible ability that has previously been overlooked: record-breaking tongue speed.

You may have seen chameleons feed before, shooting out their tongue and glomming onto an insect before hauling it back in for a meal. But the details of this maneuver are mind-boggling. Christopher Anderson, a researcher at Brown University, found that the tiny rosette-nosed chameleon can accelerate their tongues at the incredible rate of 1.6 miles per seconds squared, or 264 G (the rate of acceleration caused by gravity). If a car could accelerate this quickly, it'd go from zero to 60 miles per hour in 0.01 seconds.

This is the fastest bodily movement of any bird, reptile or mammal, Anderson says. It is also the most powerful movement (as measured by the amount of work done in a given amount of time) of any of these creatures. Anderson calculated chameleon tongues expend more than 14,000 watts of energy per kilogram, which is roughly 14 times more work than any animal muscle is capable of.

In fact, the chameleon tongue's rapidity and power has nothing to do with muscles. Instead, the creature uses special elastic collagen fibers to build up and store energy, which is then released in an instant. The setup is quite similar to a bow and arrow, Anderson explains.

These record-breaking measurements derived from a single rosette-nosed chameleon (Rhampholeon spinosus), an endangered species found in the mountains of Tanzania that measures 2 inches in length but which catapults it tongue 2.5 body lengths. In human terms, if Michael Jordan had this ability, he could easily snag a grasshopper from off the basketball rim with his tongue while standing at the free-throw line.

Several other small chameleons had tongue speeds approaching this level. In a study published January 4 in the journal Scientific Reports, Anderson filmed 20 different species of chameleons feeding using an ultrahigh-speed camera, and measuring how far the tongue moved and how quickly. He found that the smaller the chameleon, the more power and acceleration were evident in their tongue-lashings.

Anderson obtained the chameleons from private collections, invasive populations in Florida, and various other locations, where he filmed them before letting them go in the wild.