Of all the adjectives you could use to describe a crocodile's
face, 'sensitive' might not be an obvious one. But their huge
jaws, pointed teeth and armoured scales belie a surprising
secret. Their faces, and possibly their entire bodies, are
covered with tiny bumps that are far more sensitive than our own
fingertips. The bumps are obvious if you look carefully. Each
one is a small dome, barely a millimetre wide, surrounded by a
groove. There are around 4,000 of them on an alligator's jaws
and inside its mouth. Crocodiles and gharials also have the
bumps on virtually every scale of their bodies, giving a total
of around 9,000.