Belemnites: Cephalopod Ancestors

Belemnites: Cephalopod Ancestors

Belemnites were ancient marine creatures that lived during the Mesozoic era, around 200 to 65 million years ago. They were cephalopods, related to modern squids and octopuses, but had a hard internal shell called a «belemnite guard.» These creatures were expert swimmers, using jet propulsion to move through the water.

The belemnite guard was a long, cone-shaped structure made of calcite that provided support and protection for the soft body parts of the animal. Fossilized belemnite guards are commonly found in sedimentary rocks around the world, giving scientists valuable insights into the anatomy and behavior of these ancient creatures.

Despite their extinction at the end of the Cretaceous period, belemnites left a lasting legacy in the evolution of cephalopods. Studying these fascinating creatures helps researchers better understand the development of modern cephalopods and their place in the history of life on Earth.