card
269

Tarbosaurus

OLogy Series
extinct animal
card
269

Tarbosaurus

OLogy Series
extinct animal

When the famous Tyrannosaurus rex roamed North America, a very similar dinosaur was living on the other side of the Earth in east Asia. Known as Tarbosaurus, this dinosaur was an equally powerful close cousin of T. rex. And like T. rex, this
predator walked on two feet, and had a large head with powerful jaws and huge jagged teeth.

Speedy Hunters?
How fast were big predators like T. rex and Tarbosaurus? Scientists have debated this for many years. One way they try to answer this question is with biomechanics, the study of how animals move their bodies. Scientists examine fossils and observe the muscles and movement of living species. When they wanted to understand how the massive, two-legged T. rex moved, they used fossil
information to build an accurate scale model of its skeleton. They noticed that unlike four-legged dinosaurs, bipedal dinosaurs carried their entire weight on one leg, as humans do. In addition, their long tails must have helped balance them.
Scientists also compared the movement of T. rex to a modern-day relative, the ostrich. The ostrich, which has a similar skeleton, is quite fast-reaching speeds of up to 45 miles per hour. However, the T. rex was also nearly 40 times heavier. With this in mind, scientists estimate that T. rex would have run only about 10 miles
per hour.

The Tarbosaurus had teeth about the size of a:

grape

lemon

banana

Are you right?

Correct!

Its long, curved teeth were nearly six inches long, giving it a super-sized bite. It's no wonder it could eat other dinosaurs for lunch!

By studying the brain cast of the Tarbosaurus, scientists believe this dinosaur had:

a good sense of smell

binocular vision (depth perception)

both

Are you right?

Correct!

Tarbosaurus had large olfactory lobes, the part of the brain used for smell. And both eyes were in the front of its skull (rather than on the sides), so it must have had depth perception. Both traits would have made it an excellent hunter.

Tyrannosaurids, a group of dinosaurs that includes T. rex and Tarbosaurus, did not live in the southern hemisphere.

Fact
or
Fiction
?

Fact

Tyrannosaurids were some of the largest predators to have walked the Earth. But fossil specimens have only been found in the northern hemisphere.

Scientists believe that the Tarbosaurus hunted alone.

Fact
or
Fiction
?

Fiction

Scientists have found evidence that other tyrannosaurids hunted in packs, so Tarbosaurus may have as well. And it may have had a social structure within the group.

Tarbosaurus (“terror lizard”)
Locality found: eastern Asia
Age: Late Cretaceous, about 70 mya
Size: 30-40 feet long; weighed up to five tons
Diet: carnivore (ate plant-eating dinosaurs and possibly other carnivores)
Characteristics: bipedal, with large head and tiny arms; strong jaws with sharp, serrated teeth
Cool fact: It had a good sense of smell and binocular vision.

Image credits: Sean Murtha.