Albertosaurus was a large tyrannosaur belonging to the late Cretaceous in Western North America. It was a close relative of the Tyrannosaurus  Rex, but is usually smaller and is not as heavy as it is where it also came from a different subfamily, Albertosaurinae together with the Gorgosaurus. 

Key Facts

Albertosaurus pronunciational-BERT-oh-saw-russ
What does Albertosaurus mean?The term Albertosaurus is a Greek word which means “Lizard from Alberta” in honor of Alberta, Canada after almost all fossils are discovered in the area.
Dinosaur typeTheropods
On the menuCarnivorous
Length9.0 meters
Height30 feet
Weight1500 kg
Life expectancy2 to 28 years
Legs used to get aroundBipedal
Estimated top speed31 kph (19 mph)
When they livedLate cretaceous period, 74-76 million years ago
Where they have been found?The discovery of the first Albertosaurus fossils are found in Alberta, Canada, though there are recoveries reported from American states in Montana and Wyoming.

When & Where

In a geological survey of Canada in 1884, geologist Joseph Tyler discovered the first Albertosaurus skull along the badlands in the Red Deer River in Alberta, Canada. He accidentally discovered it while he was exploring the river valley cliffs for coals. This discovery is the start of a grand age of dinosaur investigation and research in the era. 

Size & Weight

After the 1884 discovery of the Albertosaurus Skull, there were no discoveries made in the last 40 years. However, there were discoveries of a two-year-old and a 33-foot-long adult Albertosaurus. 

Mobility & Diet

Albertosaurus are known to be carnivores which explains their sharp teeth, which are perfect for flesh-eating. They utilize the “grip and rip” action to cut through the bones and flesh of their meal. Their body reveals that it’s possible that they engage in ambush and marathon hunting activity and chase their prey with a speed of about 30 kph. Furthermore, their tails can be used to change direction under speed. 

Interesting Points

  • In attacking their prey, instead of going for an outright kill, they tend to attack them using the “bite and slice” technique, which also helps them to catch prey almost the same size and even large sauropods. This theory is backed by possible evidence of pack-hunting at a site where about 20 specimens were found that seem to have died at the same time. 
  • Albertosaurus are about half the size compared to Tyrannosaurus rex. A full-grown Albertosaurus weighed 2 tons and measured about 30 feet while Tyrannosaurus weighed 7 or 8 tons and was more than 40 feet long. 
  •  They usually lived in a lush and heavily vegetated semi-tropical environment during the late Cretaceous Period in Canada. 
  • They have saw-edged teeth for flesh slicing