Ammonites are a group of extinct cephalopod mollusks with ribbed spiral shells. They are exceptionally diverse and well known to fossil lovers. Researchers have developed the first biomechanical model ...

These extinct shelled cephalopods ruled the ocean for 300 million years. But how they swam and shaped the seas remains a mystery. "Snake stones" or ancient sea creature? Credit: opacity/flickr/CC ...

Robotic ammonites, evaluated in a university pool, allow researchers to explore questions about how shell shapes affected swimming ability. They found trade-offs between stability in the water and ...

Ammonites are a tale of two textures. The prehistoric cephalopods were composed of fleshy soft tissue (the living bit of the animals) and hard external shells, which, according to a paper published ...

The muscles and organs of an ammonite — an extinct relative of cuttlefish and squid with coiled shells and tentacles — have been reconstructed in 3D for the first time. The achievement has allowed a ...

In Baculites, a straight shelled ammonite, the constructional limits on shell shape resulting from the limited strength of nacre in tension are circumvented by a system of vaults in the phragmocone.

If you’ve ever been in a shop that sells fossils — the natural history museum gift shop, the nature store in the mall, and so on — you’ve probably seen an ammonite. Its chambered coils make a distinct ...

For one unfortunate ammonite in the Late Jurassic, this was no dream but a harsh reality. The animal died utterly unclad, outside its whorled shell, and was buried this way. According to a study ...

Ammonites are a group of fossil marine mollusk animals closely related to living cephalopods (i.e., octopuses, squid, and cuttlefish) and shelled nautiloids such as the living Nautilus species. The ...

Ammonites are among the most common marine fossils from the age of the dinosaurs, but no one has found one like this before. It shows one of the swimming marine molluscs without its distinctive spiral ...

In a university swimming pool, scientists and their underwater cameras watch carefully as a coiled shell is released from a pair of metal tongs. The shell begins to move under its own power, giving ...