Some ammonites had long, straight shells ... progressively larger chambers separated by thin walls called septa. The animals constantly grew new shell material as they aged, but the their bodies ...

Fossils of them are found all around the world, sometimes in very large concentrations. The often tightly wound shells of ammonites may be a familiar sight, but how much do you know about the animals ...

Try to identify the species you've found from the unique shapes and features of their shells. 'Ammonite' can refer to ammonoids (animals in the class Ammonoidea) which first appeared about 450 million ...