Sea stars have a simple eye at
the end of each arm. The eye is
able to "see" only differences
of light and dark, which is useful
in detecting movement.
Starfish are almost unique in the
fact that, unlike most other animals,
they do not have blood but instead
use sea water to pump around their
bodies.
There are about 1,800 living species
of sea star, and they occur in all
of the Earth's oceans. The greatest
variety of sea stars are found in
the northern Pacific Ocean.
For
more information visit: Ocean-Life.info
