Europasaurus

Live reconstruction of a young bull and an adult specimen of E. holgeri. In the background are passing Iguanodontiden.

• Northern Germany ( Langenberg quarry near Goslar )

• Europasaurus holgeri

Europasaurus ( "lizard from Europe" ) is a genus of sauropod dinosaur and will be provided within this taxon to the original Macronaria. The only known species E. holgeri, was unusually small for a sauropod, and lived on one of the paleo- islands at the southern edge of the Lower Saxony Basin in the Upper Jurassic ( Kimmeridgian average ) in northern Germany.

Fund history

The fossils found so far come from more than eleven individuals of all developmental stages ( juvenile, sub -adult, adult) with body lengths from 1.7 to 8 meters from the quarry Langenberg near Oker, a district of Goslar ( Lower Saxony), on the northern edge of the Harz. The upcoming multi marine carbonate rocks are from the period from the early Oxfordian to late Kimmeridgian. The first teeth and bones discovered in 1998 the fossil collectors Holger Luedtke, his honor bears the epithet of the type species of his first name. The in the same year Ludtke informed of scientists considered the findings initially for the remains of juvenile Großsauropoden. They were then prepared in dinosaur Münchehagen. Along with the fossils of Europasaurus there were fish, apotosauride crocodiles, pterosaurs, turtles and theropod dinosaurs. The exposure of the bone is far from complete and can be observed in the show preparation workshop of the dinosaurs Münchehagen. Since 1999, approximately 1000 different bone Europasaurus individuals were prepared. Finds of Sauropodenschädeln are generally rare, well-preserved skull of Europasaurus are the first such fossils in Europe.

Paleobiology

The sauropods include the largest animals that ever inhabited the terrestrial ( continental ) habitats. Europasaurus shows compared to the typical sauropod gigantism opposite trend, which is interpreted as Inselverzwergung. This is a tart observed in colonization of islands by large animals significant reduction in body size than evolutionary adaptation to an isolated habitat with limited food supply.

It is assumed that verzwergte due to the enormous selection pressure of the unknown ancestor of E. holgeri within a few generations to a maximum of about one ton and 8 meters. Camarasaurus, the closest known relative was three times as long and weighed about 30 tons. It is not yet clear whether the ancestor of Europasaurus on by rising sea ( marine transgression ) was shrinking island isolated or whether he immigrated later and subsequently reduced its height.

Histology of the long bones

The determination of the relative individual age succeeded with the help of the histology of the long bones at the University of Bonn. The bone microstructure shows that Europasaurus unlike the Großsauropoden only grew very slowly. Studies on thin ground sections of bone cross section can stand still marks in the bone seen that show growth interruptions. In the cortical bone ( cortical bone ) of the largest bones are found closely related arrest brands that prove that their growth was already completed at the time of death. This proves that it is in the largest individuals found to adult individuals who had already reached their final size.

Reconstructed skeleton

Claw

Vertebra

Row of teeth during preparation