Science: Zoology: Nautilus, Cephalopod, Mollusk

Nautilus means "sailor" in Greek. Nautiluses are members of the cephalopod family, along with other animals with prominent heads and tentacles (like giant squid). Cephalopods are mollusks. Cephalopod is Greek for "head-feet."

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Nautiluses are called "living fossils." They have existed relatively unchanged for 500 million years.

Nautiluses are the only living cephalopods with shells. The shell uses countershading camouflage: darker on top, lighter on the bottom.

They have up to 90 tentacles arranged in circles. No suckers on the tentacles.

Predator of shrimp and small fish. Found only in the Indo-Pacific on steep slopes of coral reefs.