A close look at the dinosaurs: What did the prehistoric lizards eat?

Sauropods were still quite small after hatching. When fully grown, they weighed 2500 times their original weight. "We can therefore assume that the little ones ate different food and also lived in different habitats than adult animals. Perhaps they occupied different niches under food pressure," surmises Tschopp. He is part of a group of international palaeontologists who are using ever newer techniques and methods to compile and analyse knowledge about the giant lizards in databases. Much about the life and development of sauropods is still unknown, including whether they practised brood care or moved on after laying their eggs.

In the morphology laboratory of the Leibniz Institute for the Analysis of Biodiversity Change (LIB) in Hamburg, Emanuel Tschopp works closely with Thomas Kaiser, Head of the Mammalogy and Palaeoanthropology Section at the LIB. Using state-of-the-art technology, he and his team analyse the surface structures of teeth. CT and surface scans as well as 3D modelling and printouts provide the researchers with information about the animals' diet and the way in which it was ingested.

The CT scan analyses can also provide information about the age of teeth and thus the speed of tooth formation. Some sauropods apparently changed their teeth every fortnight. This tooth change took place at different speeds depending on the species - which in turn provides information on the consumption of different foods. Tschopp is now investigating whether there was a difference in the diet of young compared to adult animals of the same species.

"The Hamburg dinosaurs are so important for this project because we have individuals from three different growth stages and also their skull material," says Tschopp. "This is extremely rare." One and a half years ago, the Hagenbeck Foundation secured four long-necked dinosaurs from the Flagellicaudata group for Hamburg. Rarely before have four dinosaurs of different ages been discovered at the same site - as here in the Morrison Formation in Wyoming, USA.

The fossilised parts of the four specimens are now stored at the University of Hamburg, where Tschopp's project is based. Here they are being inventoried by him and examined according to various questions - since 1 October with the support of the Humboldt Foundation.

A broad data basis is crucial for palaeontological research. The database initiated by Tschopp with information on all known sauropods from the Morrison Formation is just one source for scientific comparisons. Finds of dinosaur skeletons, teeth, entire rows of teeth or even remains of faeces or stomach contents recovered from all over the world are also digitally documented in other digital repositories. Researchers can also use these platforms to find out whether young animals were found in different zones to adult dinosaurs.

With his extensive expertise in the study of tooth surfaces of mammals and fossil hominids, Thomas Kaiser supports the dinosaur researcher: "We assume that sauropods tore off parts of plants and swallowed them whole. The stomachs of these animals must have been huge." What remains unclear, however: Palaeontologists assume that conifers, ferns and cycads dominated the plant world 150 million years ago. However, flora and fauna have changed so much in the meantime that it is difficult to draw direct conclusions about a broad food supply.

Kaiser uses dental studies on other reptiles and mammals as reference data for his investigations: "This is possible because biting and chewing are simple friction processes. We assume that the biomechanical process of gnawing, which causes the abrasion of the tooth surface, was similar."

Using coloured models of the tooth surfaces, which were produced using 3D scans, as well as silicone impressions, Kaiser can visualise the so-called abrasion marks (wear marks on the teeth) and depict the force exerted by the teeth via the texture. 3D prints of individual teeth, the jaw or an entire dinosaur skull can provide further analyses or serve as illustrative material.

"We have just started to mould and examine the teeth of the Hamburg sauropods," explains Emanuel Tschopp. "We are excited to see what insights we can gain into their diet and living environment over the next two years."