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Unlike humans and most
other mammals, crocodilians have no external ear.
Don’t assume they can’t hear, however.
Alligators and their kin do possess eardrums –
you just have to know where to find them. They are
located just behind the eyes, and are protected
by scaly, moveable flaps of skin. The positioning
of the ears, in conjunction with the nostrils and
eyes, is perfectly suited to this reptilian’s
habitat.
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Gator
Ears and Crocodile Tears -- Crocodillians
are perfectly adapted to their habitats. Locations
of eyes and ears, along with special muscles that
close off nostrils when submerged help these reptiles
survive underwater. |
It allows the alligator
to remain submerged with only the top of its head
exposed so that it can still hear, breathe and see.
Unlike most reptiles, the alligator comes equipped
with some extra features to make life in the wetlands
easier.
Many
of these special adaptations help the animal survive
in underwater. For instance, a special set of muscles
close the alligator’s nostrils when it dives.
Likewise, a special valve in the back of the alligator’s
throat prevents water from entering the mouth when
the animal is submerged. This adaptation is especially
useful when the alligator captures prey underwater.
In order to eat, however, the alligator’s head
must be above water. Finally, the alligator has
a transparent third eyelid, known as a nictitating
membrane, that covers the eyes when it swims.
Speaking of eyes, what about those famed crocodile
tears? It is true that crocodilians do produce tears
– they are secreted from glands that are similar
to human tear ducts. The tears help keep the eye
clean and lubricate the nictitating membrane. The
tears are most noticeable when an alligator has
been out of the water for some time and the eye
is drying out. While crocodilians definitely produce
tears, it’s only a myth that they cry over
their victims. Natural historians trace the origin
of the story back to a 13th Century French encyclopedia
written by the Franciscan monk Bartholomaeus Anglicus.
The image of such a predator crying after the kill
was powerful and ironic enough to become a permanent
part of popular culture even today.
Additional Resources
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