Chameleons may be the source material for many a stuffed toy and a series of really pretty strange beer commercials, but, make no mistake, when it comes to predatory behavior, they’re complete assassins. The chameleon tongue is a wonder of evolutionary engineering, enabling these old world lizards to hunt opportunistically—waiting, waiting, and then, zap. The tongue is deployed in a blur of slime, retrieving prey from up to a third of the chameleon’s body weight and from distances of over twice its body length. As such, the chameleon can essentially hunt without moving.
By Michael Byrne | MOTHERBOARD
How chameleons actually accomplish this remains something of a mystery. The „ballistic projection“ of the tongue is only part (a fascinating part) of the story—the chameleon still has to reel its prey back in to be chomped upon. It does this thanks to an extremely sticky tongue, obviously, but how this stickiness is actually implemented is of great interest to biologists and physicists. Now, according to a paper published Monday in Nature Physics by Pascal Damman and colleagues at the Université de Mons in Belgium, we may have some answers. It’s all in the spit.
More specifically, it’s all in the viscosity of the spit, which is about 400 times that of human spit. Given the right conditions, it can even behave more like an elastic solid than a proper liquid, however sticky. This is key.