Gravitholus (meaning 'heavy dome') was a genus of pachycephalosaurid dinosaur from the late Cretaceous period (Campanian stage, around 75 million years ago). It was a pachycephalosaur, and like other pachycephalosaurids the skull roof formed a thick dome made of dense bone, which may have been used in head-butting contests over mates or territory. It lived in what is now Alberta, Canada, and was described in 1979 by W. P. Wall and Peter Galton. The type species is Gravitholus albertae.

Gravitholus
Temporal range: Late Campanian, 75 Ma
Skull TMP 72.27.01
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Ornithischia
Clade: Neornithischia
Clade: Pachycephalosauria
Family: Pachycephalosauridae
Genus: Gravitholus
Wall & Galton, 1979
Species:
G. albertae
Binomial name
Gravitholus albertae
Wall & Galton, 1979

There is some debate amongst paleontologists as to whether the animal represents a distinct genus, or if it is synonymous with Stegoceras. Some recent publications indicate it may be a valid genus.[citation needed] Gravitholus was initially described as one of several pachycephalosaurids known from Dinosaur Park, including Stegoceras validum, Hanssuesia sternbergi and Foraminacephale brevis. It is unclear whether all of these species would have lived in the area at the same time. A 2023 publication by Dyer et al. found Gravitholus and Hanssuesia to be synonymous with Stegoceras, thus decreasing the diversity of Dinosaur Park pachcephalosaurids to only two valid taxa. This conclusion was reached because new morphological data recovered from synchrotron scanning of the skull revealed Gravitholus to be virtually identical to mature Stegoceras.[1]

See also

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References

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  1. ^ Dyer, Aaron D.; Powers, Mark J.; Currie, Philip J. (2023). "Problematic putative pachycephalosaurids: Synchrotron µCT imaging shines new light on the anatomy and taxonomic validity of Gravitholus albertae from the Belly River Group (Campanian) of Alberta, Canada". Vertebrate Anatomy Morphology Palaeontology. 10 (1): 65–110. doi:10.18435/vamp29388. ISSN 2292-1389.
  • Wall, W. P. & Galton, P. M. (1979). "Notes on pachycephalosaurid dinosaurs (Reptilia: Ornithischia) from North America, with comments on their status as ornithopods". Canadian Journal of Earth Sciences. 16:1176-1186
  • Maryańska, T., Chapman, R. E., and Weishampel, D. B. (2004). "Pachycephalosauria". In D. B. Weishampel, P. Dodson & H. Osmólska (eds.), The Dinosauria (second edition). University of California Press, Berkeley 464–477
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