MOLLUSCS AMMONITES (CONTINUED)
Cephalopod molluscs, as well as being ecologically important today, also have a fossil record going back
to the beginning of complex animal life during the Cambrian. Ammonites dominated most marine
environments for a period of 300 million years, from the Late Silurian to the end of the Cretaceous
about 65 million years ago, when they died out with many other groups in the mass extinction of the time.