Description:
Presented is an excellent quality Albertasaurus dinosaur tooth found
in Northern Montana in the Judith River Formation. This is a historically
important area. Early paleontologists like Edward Drinker Cope explored
here as early as 1876.
Albertasaurus
(meaning "Alberta lizard") is a genus of tyrannosaurid
theropod dinosaur that lived during the Late Cretaceous Period,
more than 70 million years ago in western North America.
Although a large theropod, Albertasaurus at 2 tonnes was much smaller
than its more famous T-Rex. Some 20 Albertasaurus have been found,
providing detailed anatomical data; 22 at one site in Alberta shows
evidence of pack behavior and ontogeny data.
All
tyrannosaurids, including Albertosaurus, shared a similar bauplan.
As is typical for a theropod, Albertosaurus was bipedal and balanced
the heavy head and torso with a long tail. However, tyrannosaurid
forelimbs were extremely small for their body size and retained
only two digits. The hind limbs were long and ended in a four-toed
foot. The first digit, called the hallux, was short and only the
other three contacted the ground, with the third (middle) digit
longer than the rest. Albertasaurus may have been able to reach
speeds of 25–30 miles per hour
The
type species, Albertasaurus sarcophagus, was occurred in the province
of Alberta, its namesake. Some scientists consider Gorgosaurus libratus
as a second species of Albertasaurus.
Note
the fine serration of the tooth, a tell-tell sign of the fierce
Theropod dinosaurs. The suborder first appeared in the Carnian age
of the Late Triassic period some 230 million years ago becoming
the sole large terrestrial carnivores from the Early Jurassic until
the end Cretaceous mass extinction some 65 Ma. There remaining genetic
legacy are more than 9000 living bird species that evolved in the
Late Jurassic from the small and specialized coelurosaurian dinosaurs.
The characteristics linking theropods to birds are the three-toed
foot, a furcula (wishbone), air-filled bones and (in some cases)
feathers as well as brooding of their eggs.
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