Belemnites

Neale Monks (UK) Belemnites are common fossils, and most collectors will have a few of these distinctive, bullet-shaped fossils in their collections. In fact, belemnites have been recognised as something other than mere stones for thousands of years. As a result of their remarkably phallus-like shape, the Ancient Egyptians associated them with their male fertility god Min. Mediaeval Scandinavians believed that elves used them as candles, while in England they were called Devil’s thunderbolts and were thought to have been formed during lightning storms. Belemnites even had magical uses. In pre-industrial England, one remedy for eye infections of horses was to grind them up and blow the dust into the poor animals’ eyes. But what sort of animals were belemnites? Where did they live and what did they eat? And what was the function of that heavy, conical calcite structure we know today as the belemnite guard? Fossil belemnites When belemnite fossils are found, it is usually only the calcitic guard that is present. That the thing is made from calcite is unusual – most cephalopod shells are made from aragonite. This holds true for nautilus shells and cuttlefish shells today, and ammoniate shells in the past. Fig. 1. Comparing a life-sized model belemnite with a common fossil find. The fossil belemnites are actually only a small part of the animal, since the soft tissue would have decayed away. In fact, the chambered part of belemnite shells was made from aragonite and greatly resembled the chambered shells of other cephalopods. … Read More