What are Nautiloids?
Nautiloids are a subclass of cephalopod mollusks, related to other cephalopods such as squid and octopuses. Only a few modern species of nautiloids exist, such as the Chambered Nautilus, but nautiloids are an extremely important fossil group, with specimens dating back to 515 million years ago, during the Late Cambrian era. Nautiloids were the first cephalopods, and were one of the first “advanced” animals to appear in the Cambrian, with relatively large brains and nervous systems. The heydey of the nautiloids was during the Paleozoic era, from about 515 to 251 million years ago. During this time, they were the top predators of the seas, and developed a wide range of shell forms. Nautiloids were the first cephalopods, evolving from simpler molluscs and occupying the predator niche. In just 50 million or so years, they went from only a few millimeters in length to 8 meter (26 ft) giants like Cameroceras, thought to have been the biggest animal on the planet at the time when it lived, th
Nautiloids are related to ammonites, squids, cuttlefish and octopus, and belong to a group of creatures called cephalopods. They have shells which are divided into chambers filled with gas. All of the chambers of the shell are connected by a tube which allows regulation of buoyancy by changing gas pressure inside the shell. This and a simple jet propulsion system allow the animal to move quickly and precisely. The nautiloid animal lives in the largest outermost chamber of the shell. It has large, complex eyes, strong beak-like jaws and muscular tentacles. Nautiloids are predators, feeding on smaller animals on the reef.
