T. rex will come to LeidenPosted on 20-12-2014 by Pauline Lössbroek
We will soon welcome the new Tyrannosaurus rex skeleton, which we excavated in Montana in 2013.
Preparation of the fossil is currently in progress, and in the next two years we hope to learn everything we possibly can about this specimen. She will make her first public appearance in the temporary dinosaur exhibition scheduled for 2016, and by that time we want to be able to share the full story of the specimen in that exhibition.
What have we learned already? The skeleton is extraordinarily well-preserved, with hardly any distortion to the bones. Preparation is currently ongoing, and we expect to have about half of the elements preserved. The skull is reasonably complete; the neck, dorsal vertebrae and the better part of the tail is preserved, and the hip, part of the shoulder, and the right leg are present, too. The feet, left leg and the arms are missing.
It’s an adult individual – a very mature adult, and it has been suggested that the “robust” and the “gracile” form of T. rex represent sexual dimorphism, with the “robust” form being the female. Initial field measurements suggest the Naturalis specimen is a “robust” specimen and hence a female.
For now, the research plans, in addition to a detailed description of the specimen will cover at least the following topics:
- Geological setting — In collaboration with Amsterdam VU University and Utrecht University, the sedimentology, magnetostratigraphy, pollen, and milankovich cyclicity is being addressed.
- Age & ontogeny — The Naturalis T. rex is a very old individual; this skeleton will allow us to explore the far end of T. rex ontogeny. For a start, in collaboration with the Vrije Universiteit Brussels (Belgium), various bone samples will be analysed for LAGs (“growth rings”) to determine the minimum age of the individual.
- Paleopathology — Already during the excavation, multiple pathologies were recognized, including healed bite marks on the skull, healed fractures on various limb elements, and various other lesions. Together with the LUMC academic hospital in Leiden and Manchester University we will evaluate the medical file of the Naturalis rex.
- Stable isotope analysis — Analysis of 13C and 18O in tooth enamel provides insight in diet, body temperature, and a handful of other factors. Serial sampling of the growth lines in tooth enamel could even provides clues to possible migration patterns. Together with the stable isotope laboratory at Amsterdam VU University we should be able to learn more about this.
- Biomolecules — Occasionally, recognizable remains of biomolecules (fragments of proteins, et cetera) get preserved in fossils; together with Manchester University we will evaluate the preservation of biomolecules in this specimen.
- Locomotion — The team at Manchester University is hard at work in improving our understanding of the locomotion of T. rex. Dimensions of the legs of the rather old Naturalis specimen will provide an interesting additional data point in these analyses.