 Cephlapoda
The class cephlapoda consists of octopuses, squid and nautiloids.
Cephlapoda means head and foot and in most of this class the
head lies close to the feet. In octopuses and squid, the head
forms a sort of funnel.
Special pigment cells in their skins, chromatophores, allow
them to change color rapidly. This is a great advantage to escape
from predators as well as invite mates.
Octopuses and squid have an ink sac that is used for protection.
When the animal becomes alarmed, it can expel the ink. This ink
screen effect can help confuse predators while the animal escapes.
Cephalopods have the most complex brain of any invertebrate.
They have very complex eyes and complex learning behavior.
These creatures have a siphon which can expel waste and ink
and is also used for movement. This sort of jet propulsion results
in very fast locomotion in some species.
Around their mouths, they have bear-like jaws with poisonous
glands. Arms and tentacles have suckers on them used used to
capture manipulate, and grasp food.
Reproduction in squid is sexual. The male squid produces
spermatophore (bag of sperm) and uses a specialized arm to transfer
the spermatophore sac to the female. The female places the sac
inside of her and once fertilized, she places the eggs into a
jelly matrix attached to anything she can. Once the female has
placed all the fertilized eggs, she dies.
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