Europasaurus (lat.: Europasaurus; “lizard from Europe”) is a relatively small herbivorous dinosaur, one of the earliest representatives of the Macronaria clade from the infraorder Sauropoda (Sauropoda).
The only representative of this genus known to science, the species Europasaurus holgeri (“Holger’s Europasaurus”), was unusually small for a sauropod and lived in the Upper Jurassic period (Middle Kimmeridgian) in the territory of modern Northern Germany, on one of the paleo-islands of the southern edge of the Lower Saxon basin.
The Europasaurus fossils found so far belong to more than 11 individuals of all ages (that is, juveniles, adolescents and adults) with a body length of 1.7 to 8 meters, which were discovered in the Langenberg quarry (Germany).: Steinbruch Langenberg) near the Nizhneson city of Goslar (Goslar), near the northern edge of the Mountain Massive Harz (Harz).
The sedimentary carbonate rocks occurring there belong to the Jurassic period between the early Oxfordian and late Kimmeridgian stages. The first teeth and bones were discovered in 1998 by fossil collector Holger Lüdtke (German).: Holger Ludtke); in honor of which the dinosaur was given the specific epithet “holgeri”.
The scientists, to whom Ludtke informed about this in the same year, at first mistook the bones found for the remains of a cub of some large sauropod. Then these fossils were dissected in the Dinosaur Park in Münhehagen (German.: Dinosaurierpark Münchehagen).
Fossils of fish, prehistoric crocodiles, pterosaurs, turtles, and theropod dinosaurs have also been found along with the Europasaurus fossils. Since 1999, about 1000 bones of different individuals of this dinosaur have been dissected in the Dinosaur Park. The finds of the skulls of Zauropodes are usually a rarity, and the wellpreserved bones of the skull of the European capaen became the first fossils of this kind discovered in Europe.
Sauropods are the largest animals that have ever inhabited the living spaces of the continents. Unlike other sauropod dinosaurs, which were characterized by gigantism, Europasaurus, apparently, went the opposite way of evolution, which is interpreted as an island shredding of species.
We are talking about the currently observed significant decrease in body size of large animals when they populate islands, which is the result of their evolutionary adaptation to an isolated habitat with limited food resources.
Paleontologists proceed from the fact that under the enormous pressure of natural selection, the unknown ancestor of the Europasaurus Holger has greatly decreased in size over the course of just a few generations: as a result, its length no longer exceeded 8 meters, and its body weight was approximately 1 ton. Even the closest relative of Europasaurus, Camarasaurus (lat.: Camarasaurus), was 3 times longer than it and weighed about 30 tons.
It has not yet been clarified whether the ancestor of Europasaurus turned out to be isolated on an island, the area of \u200b\u200bwhich was decreasing due to the rise in the level of the world ocean, or whether it moved there later and only after that it decreased in size.
The relative age of dinosaur specimens was determined by scientists at the University of Bonn using the histology of tubular bones. The microstructure of these bones shows that, unlike large sauropods, the body growth of Europasaurus was very slow.
Studies conducted on preparations of a thin transverse section of bone material made it possible to identify traces of growth arrest in the bones, indicating that the growth of the dinosaur periodically stopped. In the outer layer of the largest tubular bones, tightly grouped rings are found due to the suspension of growth, which show that by the time of the death of the individuals that belonged to these bones, the process of their growth was already completed.
And this proves that the largest fossils found are the bones of adult specimens of Europasaurus, which have already reached their final size.
