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 ...

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 ...

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 ...

A shelled fossil discovered in an amateur’s collection may harbor the first direct evidence of prehistoric sharks eating ammonites some 150 million years ago. The palm-sized ammonite, an extinct ...

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 ...

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 ...

The narrower shells, for example, produced less drag and were more stable when moving straight through the water. The wider shells, while making for slower, less energy-efficient travel, could change ...

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 ...

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 ...

Scientists devised a mathematic model that helps explains how Nipponites, some of the wonkiest ammonites, built their shells. By Sabrina Imbler If you’ve seen one ammonite, you may think you’ve seen ...

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 ...

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 ...