Weatherproof tongues help chameleons nab prey even at icy temperatures



Tue, 09 Mar 2010: 

Washington, March 9 (ANI): While cold weather conditions typically slow down muscle performance in most creatures, a new study has shown that chameleons can nab prey even at near-freezing temperatures thanks to their tongue.


The new research, led by Christopher Anderson, a University of South Florida intrative biologist, has revealed that the tongue of this lizard shoots out like a rubber band gun, maintaining high function at even very low temperatures.


According to researchers, understanding how chameleons' ballistic tongues work could lead to advancements in prostheses, sports equipment and more.


The chameleon's near weatherproof tongue gives these reptiles an edge over competitors. These lizards can exploit a wide range of environments as well as early morning peaks in prey activity even in the chilliest of alpine climates, according to the study.


Anderson said that a chameleon's tongue works similar to a spring in a ballpoint pen, a rubber band handgun or a bow and arrow.


For the study, Anderson and co-author Stephen Deban filmed five veiled chameleons (Chamaeleo calyptratus) feeding on crickets at a range of distances.


They placed the insects on what they called a "cricket trapeze," so that the chameleon's tongue could complete its trajectory naturally without being stopped by an immovable target.


The researchers next lowered temperature during the feeding events. Prior studies determined that when other animals sprint, swim and jump, their muscle power decreases by at least 33 percent over each 10-degree Celsius (18-degree Fahrenheit) temperature drop. Chameleon tongue speed, in contrast, fell by only about 10 percent over this same temperature reduction.


"Since chameleons worldwide feed in a similar manner, we believe our findings apply to all chameleons, from species living in desert habitats to those in alpine zones," Discovery News quoted Anderson as saying.


The study has been published in this week's Proceedings of the National Academy of Sciences. (ANI)