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 ...

Despite their incredible success, ammonites died out at the end of the Cretaceous in the same mass extinction that killed the ...

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 ...