Those magnificent chameleons and their ballistic tongues

By Dr Anina Lee

Have you ever given much thought to animals’ tongues? We all have them – dogs, cats and people. Frogs use their tongues to catch prey and butterflies have coiled mouthparts that they unfurl to suck nectar from flowers. But probably the most amazing tongue belongs to the chameleon. As readers probably know by now, we at Whale Coast Conservation are particularly partial to chameleons.

Chameleons are ambush predators. Their weapon of choice is the tongue. When they spot a potential prey, they keep very still, and focus both eyes on the insect before launching the ballistic tongue. The attack is lightning fast – it lasts only a fraction of a second.

With the advent of ultra-slow motion photography, it has been possible to see exactly how the chameleon does what it’s been doing successfully for millions of years.

A chameleon’s tongue is made up of many different parts. A look at the diagram may help us visualise the parts. We know about the very sticky end (7) that sticks to its prey and can rip it off its perch. The stickiness is due to very viscous saliva that is 100 times stickier than human saliva. In other words, it sticks like glue. To help hold on to the prey, there is also a small flap of skin at the sticky end (8) that ‘pouches’ the prey to make sure it doesn’t escape.

At the other end – the chameleon end – the tongue is attached to the hyoid apparatus (1 & 2) at the back of the chameleon’s throat. There is a long bony projection from the hyoid – called the entoglossal process or horn (3) – that lies inside the mouth, pointing forward. You can imagine that this bony horn is at the heart of the missile, aiming at the prey.

Click below to read more. (The full article can be found on page 24)