Three times in the history of the earth, ammonites began to unroll their shells. In doing so, they took on the most diverse and sometimes crazy-looking shapes.

But what was the trigger that caused the shell shapes to change so bizarrely?

It is now known that there is a direct link between a rise in sea level and the appearance of such ammonites: every time such forms developed, the sea level was rising sharply.

A rise in sea level, as is happening today, considerably reduces the habitat on land. So in a few decades, we will no longer be able to go on vacation in the Maldives or ride our bikes in the Netherlands. However, sea creatures will be happy: their habitat will increase. Heteromorph ammonites seem to have loved precisely such shallow water areas. They developed countless shell forms adapted to the numerous newly created living areas and ecological niches.