Messel Prehistoric Horse @museum.de

F: We're going to be travelling way, way back in time. To a period about 55 million years ago. The Age of the Dinosaurs had ended. The time of the mammals had arrived. In the Eocene Period, their development accelerated, and countless new species emerged.

M: There are numerous fossil finds of horse-like skeletons from that period of the Earth's history. They're known as prehistoric horses. In the early Eocene, they were about the size of a fox. So they looked quite unlike our modern horses.

F: The skeleton on display in the showcase is from such a prehistoric horse. It was discovered in 1985 at the Messel Pit near the city of Darmstadt. That former open-cast mine is now one of the most important fossil sites in Germany. Millions of years ago, the Messel Pit was a volcanic crater.

M: Gradually, the crater filled with water and mud. At the bottom of this newly formed lake, conditions were virtually oxygen-free: perfect for the formation of fossils.

F: But what makes the Messel Pit unique, is that it regularly yields complete, fully preserved skeletons. Some finds even include details of soft tissue. Take a closer look. Can you make out the gastro-intestinal tract?

M: With the help of special microscopes, it was possible to determine the stomach contents – even after millions of years: The prehistoric horse’s diet consisted mainly of leaves, but also fruit. Even grape pips have been found. More information about the animals' diet is revealed by their molars. The cusps are rounded, rather than flat – the typical dentition of a leaf-eater.

F: Which is hardly surprising. The prehistoric horse lived in a lush rainforest with a hot and humid climate. Though the climate and vegetation changed, it did so gradually, over many millions of years. The dense rainforest receded, the weather grew colder, and extensive grassland developed. The leaf-eating prehistoric horse evolved into the grass-eating modern horse.

M: Its small size meant the prehistoric horse was perfectly adapted to its habitat. It was nimble and agile, able to dart through the bushes and undergrowth. Note the curved spine and short legs. Gallop or other gaits (familiar from modern horses) were physically impossible. Besides, the prehistoric horse still had 14 toes with tiny hooves. During the course of its evolution, the outer toes receded and the middle toe developed into a single hoof.

F: Perhaps you’d like to see a prehistoric horse in action? No problem. Your audio guide includes a short video that brings the "old bones" back to life.