The skin on a human and on some animals might
not look and feel the same but they serve the
same purpose; to protect the delicate tissues
underneath. For animals, their coverings also
serve as protection from the harsh environments
as well as predators. There are many types of
animal coverings. for the mammals, they have
skin that can grow and repair itself. It is also
elastic, stretching to allow the animal to move
in a lot of different ways. Insects, however,
are normally covered with a hard, inflexible
outer shell. This is excellent protection
against other animals that might attack it.
However, it does not allow the insects much
movement.
Another important role of the covering is to
provide the animal with a water resistant seal,
that is, it provides a barrier for water to
enter or exit the animal. For land animals, the
skin prevents water from leaving the body by
locking in the moisture. Otherwise, land animals
will quickly die and shrivel if exposed to air
for too long. For aquatic animals however, the
opposite happens. Too much water in the aquatic
animals' bodies can be fatal.
Many vertebrates have a covering on top of
their skin that provides added protection. Hair,
fur, and feathers help to insulate animals from
the cold, just as a winter coat keeps you warm
on a cold day. These coverings, as well as
scales, also protect the skin. |