Why not uncoil?
Ammonites from the Lower Chalk are very distinctive and developed into a range of bizarre forms. Scaphites is one of those – as you can see, it started to uncoil. It’s thought that ammonites began to experience stress from climate change and that led them to evolve into a whole new range of forms. It didn’t do them much good though, as they became extinct at the end of the Cretaceous period along with the dinosaurs and two thirds of life on the planet. How did Scaphites make a living? It’s suggested that they simply hung about in the sea filtering water for food.
Find out more about ammonites on the molluscs pages.