Mini-dinosaurs emerge from quarry

The creature was of the sauropod type - that group of long-necked, four-footed herbivores that were the largest of all the dinosaurs.

But at just a few metres in length, this animal was considerably smaller than its huge cousins, scientists report in the journal Nature.

The team thinks the Jurassic species evolved its small form in response to limited food resources on an island.

Martin Sander, from the University of Bonn, and colleagues studied the remains of over 11 sauropods found in a quarry at Oker, near Goslar, Lower Saxony.

With total body lengths ranging from 1.7 to 6.2m (5.5-20ft), the team originally thought the dinosaurs were juveniles. But when the scientists examined the fossils closely, they realised they were dealing with dwarf creatures.

The species has been given the formal classification Europasaurus holgeri, or "Holger's reptile from Europe". The name honours Holger Luedtke, a self-taught palaeontologist who found the first bones in 1998.

In height terms, an adult E. holgeri would have been about the size of a horse at the shoulder. Compare this with other sauropods, which were bigger than buses, tens of metres in length and could weigh 100 tonnes or more.

The fossils were found in Late Jurassic carbonate rock (about 150 million years old). At this period in Earth's history, much of what is now central Europe was under water. Dr Sander and colleagues suggest the dinosaurs could have lived on one of the large islands around the Lower Saxony basin.

"Such islands would not have been able to support large-bodied sauropods," they write in Nature.

"The ancestor of the Europasaurus would have dwarfed rapidly on immigrating to the island, or as a response to shrinking land masses caused by rising sea levels."

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Martin Sander
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