Hooks, paperclips and balls of string: Understanding heteromorph ammonites

Neale Monks (UK) Heteromorph ammonites were a group of externally shelled cephalopods that were particularly diverse during the Cretaceous period. Many species were abundant and geographically widespread and, for this reason, they have been used to date and correlate rocks. Unlike regularly coiled ammonites, which underwent a steady decline in… … Read More