Dinosaurs in the spotlight: What did these long-extinct animals eat?
Humboldt Fellow Emanuel Tschopp wants to learn more about the way of life of the Hamburg dinosaur group through the analysis of wear and replacement of teeth. An important place for his international studies is the morphology laboratory at LIB-Hamburg. © LIB, Gerisch.
“The Hamburg dinosaurs will play a key role in the project.” Humboldt Fellow Emanuel Tschopp wants to learn more about the way of life of the long-necked dinosaurs through analysis of the wear and replacement of their teeth. An important place for his international studies is the morphology laboratory at the LIB-Hamburg.
Sauropods were quite small after hatching. When fully grown, they weighed 2500 times their original weight. “We can assume that the little ones ate different food and lived in different habitats than adult animals. Perhaps they also occupied different ecological niches,” Tschopp suspects. He belongs to a group of internationally working palaeontologists who are using ever newer techniques and methods to compile and analyse knowledge about these giant animals in databases. Much is still unknown about the life and development of the sauropods, including whether they cared for their young 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. With the help of state-of-the-art technology, he and his team analyse the surface textures of teeth. CT and surface scans, as well as 3D modelling and printouts, provide the researchers with information about the animals’ diet and how it was ingested.
3D scans and individual teeth or an entire dinosaur skull and their printouts provide palaeoanthropologist Thomas Kaiser with clues about food intake or serve as illustrative material. © LIB, Gerisch.
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 about every 14 days. This replacement of teeth occurred at different rates depending on the species – which in turn provides conclusions about 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 material from their skulls,” Tschopp says. “That is extremely rare.” A year and a half ago, the Hagenbeck Foundation secured four long-necked dinosaurs of the Flagellicaudata group for Hamburg. Rarely before have four dinosaurs of different ages been discovered at the same site – like here in the Morrison Formation in Wyoming, USA.
In the meantime, the fossil parts of the four specimens are 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 of the Morrison Formation is only one source for scientific comparisons. Other digital repositories also digitally document finds of dinosaur skeletons, teeth, entire rows of teeth or even remains of faeces or stomach contents recovered all over the world. Through these platforms, researchers also learn whether juveniles were found in different zones than 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 unchewed. The stomach of these animals must have been huge.” Several aspects remain to be answered, however. Paleontologists assume that 150 million years ago, conifers, ferns and cycads dominated the plant world. But 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 tooth 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 tooth surfaces made via 3D scans and silicone impressions, Kaiser can visualise the so-called abrasion marks (wear marks on the teeth) and use texture to show how the teeth were subjected to force. 3D prints of individual teeth, the jaw or an entire dinosaur skull can provide further analysis or serve as visual aids.
“We have just started moulding and examining the teeth of the Hamburg sauropods,” explains Emanuel Tschopp. “We are excited to see what insights we can gather about their diet and living environment over the next two years.”
Contact:
Dr. Emanuel Tschopp
University of Hamburg
LIB – Leibniz Institute for the Analysis of Biodiversity Change, Hamburg
Tel.: +49 40 42838-5621
E-Mail: Emanuel.Tschopp@uni-hamburg.de
Prof. Dr. Thomas Kaiser
Section Head Mammalogy and Palaeoanthropology
LIB – Leibniz Institute for the Analysis of Biodiversity Change, Hamburg
Tel.: +49 40 42 838-7653
E-Mail: Thomas.Kaiser@uni-hamburg.de