The new species (Daspletosaurus wilsoni, 76.5 Ma) is transitional in form and age between D. torosus (77 Ma) and D. horneri (75.6 Ma). This suggests that Daspletosaurus underwent linear evolution – where one form evolves into the next without splitting or branching.
Badlands Dinosaur Museum
Northeast Montana has once again produced an unusual fossil find — a new ancestor of the formidable Tyrannosaurus rex.
Daspletosaurus wilsoni — Wilson’s frightful reptile — is believed to link two other Daspletosaurus dinosaurs, according to a recently published research paper by Montana State University student Elias Warshaw and Badlands Dinosaur Museum curator Denver Fowler, an MSU grad.
“What we’re saying in the paper is that the three species of Daspletosaurus that we have right now — which is Daspletosaurus torosus, which is the earliest one; Daspletosaurus wilsoni, which is what we just named and is the middle one; and Daspletosaurus horneri, which is the youngest one — we’re saying that instead of representing three different branches off of the Tyrannosaur family tree, we think that they represent an ancestor descendant sequence,” Warshaw explained.