Unlike those examples, however, ammonites had protective outer shells – and those shells didn't maintain one consistent shape throughout the fossil record. Led by postdoctoral fellow David Peterman ...

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 ...

The ammonoids, an extinct subclass of cephalopods, offer a remarkable window into the evolutionary innovations of marine life. Their coiled, chambered shells and intricate suture patterns record a ...

Some fossils of long-extinct sea creatures display brilliant rainbow colors. Known as ammolite, these gems come from the fossilized shells of ammonites, squid-like marine animals that vanished with ...