The fossilized stays of the triceratops specimen often known as ‘Large John’ show accidents to the cranium which will have occurred throughout fight with one other triceratops, in response to new analysis printed in Scientific Studies.
Triceratops (Triceratops horridus) is a species of horned dinosaurs characterised by its massive neck frill fashioned from prolonged patietal and squamosal cranium bones. It has been steered that this bony frill served as safety towards accidents from different triceratops throughout fights.
Ruggero D’Anastasio and colleagues examined the triceratops specimen often known as ‘Large John’, so named for its massive dimension, which was found in 2014 within the Higher Cretaceous Hell Creek Formation, Montana, USA. They report the presence of a keyhole-shaped opening (a fenestra) in the right squamosal bone. The bone surface around the fenestra is irregular and features plaque-like deposits of bone, which could have resulted from inflammation (possibly from infection). The authors analyzed samples taken from the larger margin of the fenestra, which reveal that the bone tissue around the fenestra is porous with lots of blood vessels compared to bone tissue further from the fenestra, suggesting that this was newly formed bone. The bone also showed signs of remodeling, as demonstrated by the presence of little pits known as Howship lacunae.
Together, these features indicate that the fenestra was caused by a traumatic injury but that the bone was healing at the time of Big John’s death. The authors suggest that the injury was caused by the horn of another triceratops, and occurred at least six months before Big John’s death. Based on these findings, the mechanisms underlying the healing process in dinosaurs appears to be similar to that in mammals.
Reference: “Histological and chemical diagnosis of a combat lesion in Triceratops” by Ruggero D’Anastasio, Jacopo Cilli, Flavio Bacchia, Federico Fanti, Giacomo Gobbo and Luigi Capasso, 7 April 2022, Scientific Reports.