Persdossier Naturalis' T. rex

Opbouw T. rex kop

Facts & Figures- The skeleton 

  • Length: 12 meter
  • Height: 4-5 meter
  • Fossil age: 67 million year
  • Skull length: 1.50 meter
  • Completeness skeleton: roughly 80% bone volume, top 3 of all T. rex fossils
  • Age: at least 30 years old. Oldest known T. rex
  • Sex: female
  • Weigt: adult T. rex 5000 kilogram
  • Dig location: Montana, United States
  • Duration of dig: August 30 - September 8 2013

The skeleton of the most famous meat eating dinosaur, Tyrannosaurus rex, has been excavated by Naturalis Biodiversity Center and is now part of its permanent collection. After having visited multiple cities with 'T.rex in Town', attracting a total of 1.149.918 visitors, Trix will now take her permanent position between the other dinosaurs in the Dinosaur Era exhibition in the renewed Naturalis.

It all began in 2013, with the dream of Naturalis general director Edwin van Huis: an own Tyrannosaurus rex in the new museum. Thanks to gifts by BankGiro Loterij, various other sponsors and a crowdfunding drive, that dream became reality in 2016. The highly complete and excelently preserved skeleton of T. rex Trix came to Leiden. After finishing her European tour with 'T.rex in Town', Trix now resides in the new Naturalis Exhibition.

Thanks to the unique way the skeleton is posed, not only are visitors are to look Trix straight in the mouth, but it also allows Trix to be the only T. rex in the world that has its real skull on its real skeleton. On top of that, the bones are very well preserved with hardly any  deformations. The quality of this fossil is in a class of its own.

Turbulent life

While excavating Trix, the Naturalis paleontologists found a number of afflictions in her bones. During her life the old lady must have endured sickness and injury

The right  fibula en one of the ribs show concrescences, indicating broken bones or an infection.

The jaws have had a rough time as well. Trix had an infection in her right upper jaw and there is a clear opening in her jawbone. It’s possible this was caused by a male T. rex while mating or during a fight. The bite wound on her upper jaw and scratches on the left part of her jawbone also suggest a fight with another dinosaur. The last of these injuries was sustained just a few weeks prior to her death.

The sacrum and the first vertebra have developed unevenly, which could point to a congenital defect or trauma sustained in very early youth. Tail vertebrae contain a number other defects as well. All this together tells us a lot of the daily lives dinosaurs led 67 million years ago.

Further information

Anne Schulp is our paleantologist and expert on T. rex. He can be reached through our communications department (, 071-7519548).

Together with researchers from the Netherlands and other countries, Naturalis is doing research into these and other fossil dinosaurs, in order to answer a host of research questions. For more information on this and other research being done at Naturalis, please visit

Press releases, pictures and further background information can be found here

Footage of the T. rex (mentioning Naturalis is obliged) is available here

Volg onze verhalen

Bij Naturalis zijn we dag en nacht bezig om de collectie aan te vullen als rijksmuseum, academisch onderzoeksinstituut en erfgoedinstelling.