Jane, the Burpee Museum's young tyrannosaur

Jane is a young tyrannosaur, 6.4 to 7 metres (21 to 23 feet) long, found in the Hell Creek Formation of southeastern Montana in 2001 and now mounted at the Burpee Museum of Natural History in Rockford, Illinois.^1,2

Jane's mounted skeleton in the Burpee Museum's 2008 exhibit layout — Jane's mounted skeleton at the Burpee Museum of Natural History in Rockford, Illinois, as it was displayed in an earlier exhibit layout. Photo (resized): Ben Jacobson (Kranar Drogin), CC BY 2.5, via Wikimedia Commons.

For most of the years since, Jane was described as a juvenile Tyrannosaurus rex. In October 2025 a study in Nature named Jane the type specimen of a new species, Nanotyrannus lethaeus.³ Not everyone who has studied the skeleton agrees: Thomas Carr told Live Science that "Jane is a juvenile T. rex."⁴

This website was built for the museum's Jane exhibit in the 2000s. It is now an independent archive. Each page has been rewritten against the published research, with its sources listed, and says so where the experts disagree or the answer is not known.

Vital statistics: how big, how old and how heavy Jane was, study by study
Is Jane a Nanotyrannus? What the 2025 study says and who accepts it
The story of Jane: discovery, excavation and the journey to Rockford
The skeleton: what was found, the bite wounds, the restored skull
Where Jane lives: the exhibit at the Burpee Museum
Kid's corner

Sources

Henderson, M. D. & Harrison, W. H. (2008). Taphonomy and environment of deposition of a juvenile tyrannosaurid skeleton from the Hell Creek Formation (latest Maastrichtian) of southeastern Montana. In Larson & Carpenter (eds), Tyrannosaurus rex, the Tyrant King, Indiana University Press, pp. 82–90.
Hutchinson, J. R., Bates, K. T., Molnar, J., Allen, V. & Makovicky, P. J. (2011). A computational analysis of limb and body dimensions in Tyrannosaurus rex with implications for locomotion, ontogeny, and growth. PLoS ONE 6(10): e26037. doi:10.1371/journal.pone.0026037
Zanno, L. E. & Napoli, J. G. (2025). Nanotyrannus and Tyrannosaurus coexisted at the close of the Cretaceous. Nature 648: 357–367. doi:10.1038/s41586-025-09801-6
Simms, C. (2025). "Nanotyrannus isn't a 'mini T. Rex' after all — it's a new species, 'dueling dinosaurs' fossil reveals." Live Science, 30 October 2025. livescience.com