Revealed: The fossil treasure chest that was home to 'missing link' Ida

Ida, a lemur-like fossil hailed by some as our 'missing link', caused a worldwide sensation when she was unveiled to the public last month.



Found in a shale pit in Germany, the creature was clearly an ancestor of modern primates and therefore evidence for Darwin’s theory of evolution, experts say .



But Ida is just one of thousands of remarkably well-preserved fossils recovered from the Messel pit in Hesse.

Star of the show: Darwinius masillae fossil known as Ida (l) - you can see an outline of where the fur once was. The 49-million year old fossil of a monkey's hand, only a few centimeters in size, was found at Messel

A Diplocynodon darwini, an extinct alligator, was completely removed from the oil shale and resin mix for display

A bat from the Eocene Era which was a crucial period in the early development of mammals

It is an unassuming crater tucked behind an industrial site with a housekeeper doubling as a security guard and only a couple of portable cabins for a trickle of visitors.

Yet it is the richest fossil site in the world for understanding the early development of mammals - and therefore ultimately man himself.

Although mammals only make up two per cent of the total finds, 45 species have been uncovered in the pit.



They include animals resembling primates, horses, marsupial possums, tapirs, rodents, bats and hedgehogs. There are also 43 species of birds, 31 species of reptiles and more than 10,000 fossil fishes.

The pit reveals a snapshot of the Eocene Epoch 48million years ago.



This was a time when mammals became firmly established as the rulers of the land, invaded the seas as whales and took to the air as bats. During the period North America, Europe and Asia were in continuous land contact.

Many of the pit's fossils are exceptionally well preserved. Usually only fragments of bones are found but Messel has yielded up full skeletons and the outlines of entire bodies as well as feathers, hair and even stomach contents.

Giant ant fossil from the Messel site near Darmstadt

Hyrachyus minimus is an extinct grazing mammal. It was a 5ft long beast suspected to be the ancestor of modern tapirs and rhinoceroses

Rhynchaeites messelense is an extinct form of the long-legged wading bird ibis. It has a long down curved bill

The ancient lake basin is currently 60m deep but the oil shale bed extends some 120-130m deeper. It measures around 700metres

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It would once have been surrounded by lush sub-tropical forests supporting an incredible diversity of life. The Messel lake bed was probably a centre point for drainage from nearby rivers.

Oil shale would have formed over a long period from mud and dead vegetation the lake bed. The lake bottom had low oxygen levels and was little disturbed by currents, so it was ideal for preserving fossils.



Scientists believe Messel was once in a tectonically active region with sub-surface shifts releasing deadly gases that killed organisms in and around the lake. This would account why there are so many non-aquatic fossils among the remains.

The fossil Amia kehreri from Messel measures 8.9" long. Fins and vertebra can be seen

Allognathosuchus, an extinct ancestor of alligators and crocodiles. It had stout jaws and bulbous teeth probably for crushing molluscs

A small bird found at Messel near Darmstadt, shows how well its feathers and body tissues have been preserved

Unfortunately many of the precious remains were lost during 1884 and 1971 when the site was actively mined for the oil inside the bituminous shale. The first fossil of a crocodile was discovered in 1875 but formal excavation did not begin until 1919.



It was not until 1966 that systematic excavations were carried out and the remains preserved by a 'transfer' technique, with resin applied to the removed fossils. But after 1971 hundreds of amateur fossil-hunters - many not properly equipped - were allowed to dig at random on the site.

Over the next two decades a number of precious fossils, including the impressive Ida, were removed by private collectors. In the early 1990s the pit narrowly escaped being turned into a landfill site.

Thankfully the area was eventually declared a natural world heritage site in 1995 and an amnesty on previously collected fossils was put into effect to get privately owned collections back into public ownership and available to science.

Digs by Darmstadt University are ongoing and experts hope the Messel pit still has plenty more fossil treasures to yield up.

The Masillamys beegeri was an early rodent with a 20cm long body and 20cm long tail. The short legs suggest a springy form of movement. Four rodents have been unearthed

A boidae snake - from a family of relatively primitive non-venomous snakes that kill by constriction