Caterpillars do not
have very good eyesight or senses. Rather than having fully-developed
eyes they have a series of six tiny eyelets or 'ocelli' on the
lower portion of their head. They rely on their antennae to help
them locate food. Many species of birds and animals consider caterpillars
to be a tasty protein snack, so the caterpillars have evolved
several methods of protecting and/or camouflaging themselves.
These methods can be either passive, aggressive, or both. Some
caterpillars have large 'false eyes' towards the rear of their
abdomen. This is an attempt to convince predators that their back
is actually their front, giving them an opportunity to escape
to the 'rear' when attacked. Others have a body coloration that
closely resembles their food plant.
self-defence measures are taken by the spitfires and hairy caterpillars.
These caterpillars have spiny bristles or long fine hairs that
will irritate anything that brushes against them, or spit acidic
digestive juices at potential enemies. However, some birds, like
cuckoos, will swallow the hairiest of caterpillars. A final grouping
of caterpillars eat the leaves of plants that are toxic to other
animals. They are unaffected by the poison themselves, but it
builds up in their system, making them highly toxic to anything
that eats one of them. These toxic species, such as the Cinnabar
moth (Tyria jacobaeae) caterpillars, are brightly striped or coloured
in red and yellow - the 'danger' colours.
1 Through 3 Are From The U.S. Fish & Wildlife Service
Images 4 Through 16 Are From The U.S.D.A.