Measured Hell Creek occurrences place Tyrannosaurus in latest Maastrichtian strata up to the K–Pg boundary; the 68–66 Ma atlas envelope is rounded and does not claim a global genus origination at 68 Ma.
claim:taxon:tyrannosaurus:fossil-rangeTyrannosaurus rex
A latest Maastrichtian tyrannosaurid represented by a large specimen sample; the dossier separates specimen anatomy and traces from fitted growth, bite-force and abundance models.
Represented range68–66 Ma
Content packagedinosauria
PBDBtxn:54833
Evidence boundary
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Claim ledger
Tyrannosaurus specimens are documented in western North American latest Maastrichtian formations; broader dispersal routes inferred for tyrannosaurids remain model-dependent and are not treated as direct Tyrannosaurus movements.
claim:taxon:tyrannosaurus:biogeographyA multi-institution growth series documents substantial ontogenetic cranial variation within referred Tyrannosaurus rex specimens, but ontogenetic assignment and synonymy remain analytical decisions rather than directly observed life histories.
claim:taxon:tyrannosaurus:taxonomyTyrannosaurus tooth marks and coprolite contents directly demonstrate bone consumption, while prey choice, population density, bite force and tooth pressure remain separate behavioural or mechanical inferences.
claim:taxon:tyrannosaurus:ecologyRobust cranial and dental anatomy and two-fingered forelimbs are repeatedly preserved, while the cited growth series shows that several skull proportions change across assigned ontogenetic stages.
claim:taxon:tyrannosaurus:morphologyKnown limits
- A missing branch or fossil occurrence does not imply biological absence. Internal nodes are not calibrated divergence estimates.
References
- Dinosaur census reveals abundant Tyrannosaurus and rare ontogenetic stages in the Upper Cretaceous Hell Creek Formation (Maastrichtian), Montana, USAHorner, J.R.; Goodwin, M.B.; Myhrvold, N. · 2011 · DOI 10.1371/journal.pone.0016574
- Time scales of critical events around the Cretaceous-Paleogene boundaryRenne, P.R.; Deino, A.L.; Hilgen, F.J.; Kuiper, K.F.; Mark, D.F.; Mitchell, W.S.; Morgan, L.E.; Mundil, R.; Smit, J. · 2013 · DOI 10.1126/science.1230492
- Open Tree of Life web servicesOpenTreeOfLife Project
- The Paleobiology Database application programming interfacePeters, S.E.; McClennen, M. · 2016 · DOI 10.1017/pab.2015.39
- A high-resolution growth series of Tyrannosaurus rex obtained from multiple lines of evidenceCarr, T.D. · 2020 · DOI 10.7717/peerj.9192
- Denormalized occurrence and taxon tables of the Paleobiology DatabaseThe Paleobiology Database Community; Kocsis, Á.T. · 2026 · DOI 10.5281/zenodo.21620933
- The Biomechanics Behind Extreme Osteophagy in Tyrannosaurus rexGignac, P.M.; Erickson, G.M. · 2017 · DOI 10.1038/s41598-017-02161-w
- Tyrant dinosaur evolution tracks the rise and fall of Late Cretaceous oceansLoewen, M.A.; Irmis, R.B.; Sertich, J.J.W.; Currie, P.J.; Sampson, S.D. · 2013 · DOI 10.1371/journal.pone.0079420