A study has discarded claims that Triceratops and the lesser known Torosaurus are one and the similar type of dinosaur. Nicholas Longrich and Daniel Field, of Yale University, looked at 35 specimens ascribed to both species and concluded they represented two distinct creatures. Where the researchers say they could not find conclusive evidence for two species was the geographical distribution of the fossil evidence.
The study shows how the skulls of this group of dinosaurs probably grew, and appear to falsify the suggestion that Torosaurus is an adult Triceratops. According to Mr. Scannella in his 2011 paper what he views as an intermediary Triceratops held by the Smithsonian in Washington. The decision of Dr Longrich is that if these were the same animal, they would also wait for to find transitional specimens in which the skull is morphing between the two skull types.