Latin Name: Nautilus pompilius
Diet: Crabs, shrimp, fish, and scavenged animals
Habitat: Found along sloping coral reefs in the tropical Indo-Pacific region. Moves to deeper waters (600-2000 feet) during the day to avoid predators, but ascends at night (to 300 feet) to hunt for prey among the corals.
Animal Size: 8 inches (20 cm)
Natural HistoryA glimpse into ancient times, the nautilus is nicknamed the "living fossil" because it has undergone few changes in the last 400 million years. Hatched at about the size of a quarter, the nautilus grows by developing its shell from four gas-filled chambers to approximately 30, growing in repeated spirals. Controlling the quantity of gas in these chambers helps the nautilus float or sink in the water column. Related to the cuttlefish, squid, and octopus, this cephalopod is unique for its fully-developed shell, poor vision, and suckerless tentacles.