You may have noticed that many lizards
flick their tongues out of their mouths.
Why do they do this? Simply put, they are smelling.
When they flick their tongues out, small amounts of
a materials 'scent' sticks to it, and then it is brought
into their mouths. Lizards have an organ called the
Jacobson's organ, that helps to process the scent. The
tissue of the organ 'absorbs' the scent, allowing the
lizard to perceive the substance. Think
about how a dog sniffs a lot when they are excited about
food, for example.
After a lizard finishes eating, they will lick their
lips to clean them. Most lizards use their tongue to
drink as well, lapping up water drops, or even from
a dish. Lizard tongues differ in shape
and size, depending on the species.
The tongue of a chameleon is highly specialized, and
are commonly called a 'ballistic' tongue. They are most
often longer than the chameleons body, and can be shot
out of their mouths at high speeds to snare their prey.
The tongue itself is composed of muscle, bone, and tendon.
The club-like tip of the chameleon tongue
is covered is thick mucus, which sticks to the prey,
and allows the chameleon to draw the tongue, with prey
attached, back into their mouths for eating.
Geckos clean their eyes with their tongues, due to
the fact that they lack eyelids.