Ancestors of cephalopods all had shells until it proved to be their biggest weakness. The ancestors of modern, squishy cephalopods like the octopus and the squid all had shells. In ancient times, ...

For the first time ever, scientists have recorded footage of the ram’s horn squid, an enigma whose common shells—really their skeletons!—have belied their vanishing secrecy. In the enchanting video ...

Collecting seashells on the beach may be a fun pastime for many. Looking at the wide variety of shells you can find, you may wonder what creature was living in it before it washed up onshore. But, ...

If you’re a beachcomber with a good eye, there’s a chance you’ve spotted a tiny, curled “horn” in the sand. So, what sea creature is it from? Padre Island National Seashore shared a photo Friday of ...

The oldest ancestor of modern octopuses lived 328 million years ago and had 10 arms, according to a new study. Researchers have named the previously unknown species Syllipsimopodi bideni after US ...

Flume experiments on 21 specimens of coiled nautiloids and ammonoids were made to obtain quantitative data on their relative streamlining. Involute shells are better streamlined than evolute forms; ...

The fossil record is chock-full of the fossilized remains of spiral-shelled ammonoids, whose shapes are reminiscent of rams' horns. But there was another type of ammonoid with long, straight, uncoiled ...

A few fun facts about the many-armed creatures. By Knvul Sheikh Octopuses, squids and their cephalopod cousins have haunted the human imagination for centuries. Their long, unfurling arms and ...