Why is the nautilus called a living fossil?
The nautilus has barely changed in over 500 million years, making it older than dinosaurs, flowers, and even trees.
The answer
Nautiluses belong to the family Nautilidae, which has existed in some form for over 500 million years, predating the dinosaurs by roughly 265 million years. While thousands of nautiloid species once thrived in ancient seas, only six species survive today, largely unchanged in shell structure from their Paleozoic ancestors. They inhabit depths of 100 to 700 meters in the Indo-Pacific, using jet propulsion and gas-filled shell chambers for buoyancy control. Unlike their cephalopod relatives the octopus and squid, nautiluses have simple pinhole eyes without lenses, up to 90 tentacles, and lack the ability to change color.
Source: Smithsonian Ocean
- nautilus
- living fossil
- cephalopods
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