The Messel Pit site has been described as an Eocene 'Noah's Ark' and is home to some of the world's most remarkable fossils, including entirely intact, fully articulated mammals. The fossils offer an astonishing glimpse into a 47 million year old ecological community. Typically the intact fossils are in a relaxed position, indicating that, like Ida, they were anesthetized by a burst of carbon dioxide from the Messel lake before they drowned. This incredible menagerie of fossils helps us understand and visualise the early relatives of today's animals.
Very early forms of horses, bats, birds, gars and turtles have all been found in the Messel Pit. Despite being separated by 47 million years of evolution, they would not look out of place in a modern zoo. Others are far less familiar – they have either become extinct or evolved beyond recognition.
Some of the most famous inhabitants of Messel are the primitive horses; some sixty nearly complete specimens have been recovered. They are the earlierst known ancestors of modern horses. However, even the smallest of today's horses would tower over their Messel counterparts, which averaged just 20 cm in height. The early horses are believed to have been browsing herbivores that fed on leaves and fruit.
The gars are a primitive fish group who survive to this day, often referred to as 'living fossils'. Outwardly, the Messel gars look scarcely different from their modern counterparts. Their massive skulls have a protruding crocodile-like snout, and a set of viciously sharp teeth. Their tough scales provided an effective coat of armour.
Bats are the most commonly found mammal group at Messel, and so far eight species have been identified. The delicate build and broad wings of the Palaeochiropteryx species indicate they were slow but agile fliers, and their preferred hunting ground was near to the ground or through low-hanging branches. Moths and small butterflies have been found in its gastrointestinal tract.
The first direct ancestors of birds appeared 115 to 105 million years ago. There are at least fifty species of birds at Messel and with hundreds of skeletons found, they account for more than half of all the vertebrate fossils. The fossil above is an unidentified species.
Today's turtles have hardly diverged from their Messel Pit ancestors, and have colonised virtually all continents and environments. Six species have been found at Messel, and there is even a site named after them - 'Turtle Hill'. Allaeochelys crepsesculpata was a soft-shelled turtle, closely related to the pig-nose turtle of Papua New Guinea and Australia, and fed on fruit, vegetation, worms, snails and fish.
This species is only known from Messel by a femur bone, but further studies revealed it was a two metre tall flightless bird, weighing over 100 kilos. Some believe it used its beak and claws to pin down and dismember its prey, although it may have been a herbivore. Gastornis were also found in Eocene North America.
The Lepticidium of Messel were odd-looking creatures. They moved like kangaroos, and had good manoeuvrability and high acceleration. The short trunks on the ends of their elongated snouts were used to sniff out prey – such as lizards, insects and mouse-sized mammals.
An extinct genus of crocodyllian, Pristichampsus grew up to ten feet in length. Bizarrely it had hoof-like toes and was probably a land dweller. It was capable of galloping, and even standing on its rear hind legs. Its teeth were sharp and serrated, ideal for hunting primitive mammals.
With the exception of bats, Macrocranion tupaiodon is the most commonly found species at Messel. Its short fur, large ears, and long hairs around the snout indicate it had well developed olfactory, tactile and auditory senses, typical of a nocturnal animal. Its powerful hind limbs indicate a fast-moving mouse-like ground dweller, able to escape from predators with a four-footed burst of speed.