❃ The nautilus is one of the ocean’s most ancient and distinctive animals, belonging to the cephalopod family alongside octopuses, squid, and cuttlefish. Unlike its shell-less relatives, the nautilus lives inside a beautiful coiled shell divided into a series of internal chambers. Nautiluses have existed in recognizable forms for hundreds of millions of years, with their lineage stretching back long before the age of dinosaurs.
❃ As a nautilus grows, it builds larger chambers and seals off the older ones behind it, living only in the spacious outermost chamber. A specialized tube called the siphuncle runs through the chambers and helps regulate gas and liquid, allowing the animal to control its buoyancy as it moves through the water. Rather than swimming quickly, the nautilus uses jet propulsion to gently cruise through deep reef slopes in search of crustaceans, carrion, and other food.
❃ Surrounding its mouth are dozens of slender tentacles used to explore its surroundings and grasp food. Unlike the suckered arms of octopuses and squid, nautilus tentacles rely on ridged, sticky surfaces to hold onto objects. With its remarkable shell, unusual anatomy, and extraordinarily ancient heritage, the nautilus is a living glimpse into a chapter of ocean history that began hundreds of millions of years ago.