Tyrannosaurus rex Tooth Progression Partial Dentary Styracosaurus Scientific Name: Borophagus secundus Location:

Scientific Name: Borophagus secundus Location: Hemphill County

Mosasaurs had four paddle-like limbs on a long

The original tooth was found in the Hell Creek Formation of South Dakota and is 5

The rock contains the detritus of shells and corals of species now inhabiting the neighboring sea (some of the coral still retaining the same red color now seen in reefs of living coral which surround the island)

Tyrannosaurus rex Tooth Progression Partial Dentary Styracosaurus Scientific Name: Borophagus secundus Location:Age: Late Cretaceous Maastrichtian ~ 65 MYA Locality: Hell Creek Formation, Harding County, South Dakota This reconstruction, showing Tyrannosaurus rex tooth progression, provides a fascinating look inside the tooth regeneration process of the most fierce predator North America has ever hosted. The exterior of the dentary is intact, while the interior provides an open window to the innermost actions taking place. The Theropod dinosaurs regrew their