![]() ![]() Paul first suggested that Tyrannosaurus rex evolved from Daspletosaurus torosus through anagenesis, a process in which an entire species gradually transforms. In his study from 1988, paleontologist Gregory S. Daspletosaurus’s eye socket is elliptical but isn’t divided. Albertosaurinae have very simple circular eye sockets, while Tyrannosaurus’s eye socket is like a keyhole-basically elliptical but divided in two by a small spike growing out of the postorbital bone. Its fossils can be found in Alberta and Montana and come from a period between 77 and 74 million years BCE.ĭaspletosaurus’s eye socket represents a link between the more basal eye sockets seen in Albertosaurinae tyrannosaurids and the ones seen in Tyranosaurus. The only notable differences between the two are that Daspletosaurus possesses proportionally larger teeth, longer arms, and smaller feet, and is overall more muscular and heavily built than Tyrannosaurus. RELATED: SHELF LIFE VIDEO: THE DINOSAURS OF GHOST RANCHĭaspletosaurus torosus is most widely accepted as the direct ancestor to Tyrannosaurus rex. This indicates that these two groups separated at one point in time and started developing different characteristics.Īccording to paleontologist Tracy Thomson, Tyrannosaurus rex originated from one of these southern North American tyrannosaurid species, probably closely related to the relatively recently found Lythronax argestes. Tyrannosaurids on the northern part of the continent possessed a ridge on their fourth metatarsal bones (bones that together with tarsi make up the upper foot), while those on the southern part did not. There were two types of tyrannosaurids in North America-the northern type (including Albertosaurus, Gorgosaurus, and Daspletosaurus ) and the southern type (including Teratophoneus and Lythronax ). Southern-type North American tyrannosaurid This idea is correspondent with the hypothesis proposed by paleontologist Phil Currie that Tyrannosaurus’s ancestor was actually Tarbosaurus. rex specimens are 68 million years old.Īccording to a study from 2013 by paleontologist Steve Brusatte, Tyrannosaurus rex was most likely an invasive species in North America, probably arriving from Asia. All specimens are dated to be approximately 70 million years old, or slightly less. ![]() Tarbosaurus remains were excavated from the Nemegt formation in Mongolia. The fact that these two animals are so similar has led some paleontologists to conclude that Tarbosaurus may just be a junior synonym of Tyrannosaurus, although not many agree with this hypothesis today. rex), a proportionally longer and narrower skull (resulting in eye sockets that are further back in the skull, giving Tarbosaurus a considerably smaller field of binocular vision), and a less massive body. The only notable morphological differences between it and Tyrannosaurus are that Tarbosaurus has proportionally smaller front limbs (yes, there are dinosaur species with even smaller arms than T. Tarbosaurus is probably the closest relative of Tyrannosaurus discovered so far. There are three main contestants: (1) Tarbosaurus bataar, (2) southern-type North American tyrannosaurid, or (3) Daspletosaurus torosus. rex’s ancestor? What dinosaur species has the honor to be called “the King’s” grandparent? However, one important question hasn’t yet been answered-who was T. We know nearly everything about it, from its anatomy to its behavior. ![]() Tyrannosaurus rex surely is one of the most well-known dinosaurs of all time. What dinosaur was the ancestor of the mighty Tyrannosaurus rex? Which dinosaur gave rise to this famous lineage? ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |