Chambered+Nautilus

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 * The Chambered Nautilus (//Nautilus pompilius// //)// **

The Chambered Nautilus is an ancestor to the octopus and the squid. They are nocturnal and dwell in the coral reefs of the Indo-Pacific Ocean. They move backwards so they can't see where they're going. To help them navigate, they use water jets that push out through the opening in their shell and are propelled backwards. They have many tentacles that use chemicals to sense the remnants of both predators and prey. The nautilus' water jet is also useful for digging through sand to get to prey. One predator is the octopus who can camouflage to catch the nautilus by surprise. Since moving takes up so little energy, the nautilus only has to eat about once a month.

 The nautilus has a chambered shell. A baby nautilus has 4 chambers while a full-grown adult has about 30. These chambers are filled with gas to aid buoyancy. The nautilus can displace this gas with liquid when it needs to dive deeper. Its diet is composed of crabs, fish, and shrimp. It may even eat animals that have died already. They tend to grow to be about 8 inches in length.

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