An Ultimate Guide to Gorgosaurus: The Dreadful Lizard

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Name MeaningDreadful Lizard Height3 meters (9.8 feet)
PronunciationGor-go-sore-usLength8-9 meters (26-30 feet)
EraMesozoicLate CretaceousWeight1,996-2,994 kilograms (4,400-6,600 pounds)
ClassificationDinosauria, Saurischia, & TheropodaLocationNorth America

Gorgosaurus Pictures

Recreation of the subadult specimen of Gorgosaurus
Recreation of the subadult specimen of Gorgosaurus | Levi Bernardo via Wikimedia Commons CC A-SA 3.0

The Gorgosaurus

Gage Beasley Prehistoric's Gorgosaurus Concept
Gage Beasley Prehistoric’s Gorgosaurus Concept

The Dreadful Lizard Gorgosaurus is one of several Tyrannosaurids that dominated North America during the Cretaceous period.

While the most known Tyrannosaurid is the infamous Tyrannosaurus Rex, Gorgosaurus was a slightly smaller dinosaur that came a few million years earlier.

Gorgosaurus lived around 76.6 to 75.1 million years ago in the Late Cretaceous period, and they had a large range in prehistoric North America.

There have been an abundance of Gorgosaurus fossils discovered, which have not allowed paleontologists to learn alot about this dinosaur, but also suggested they were a very dominant animal in their environment. 

This article will cover everything you’d want to know about one of North America’s ancient superpredators, Gorgosaurus

Fossils from Gorgosaurus have been essential in learning about Tyrannosaurids overall, and there may be new discoveries in the future that bring more insight into these ancient lizards. 

Gage Beasley's Prehistoric Shirt Collection
Gage Beasley’s Prehistoric Shirt Collection
Gage Beasley's Prehistoric Plush Collection
Gage Beasley’s Prehistoric Plush Collection

Physical Characteristics

Gorgosaurus roaring in a smoke background
Gorgosaurus roaring in a smoke background | Kitti Kahotong via iStock

Gorgosaurus was not the largest of Tyrannosaurids, and was smaller than giants like Tyrannosaurus, but had a similar size to the Albertosaurus

Like all theropods, this dinosaur’s head was very large, they had small arms, walked on two legs, and had a long tail to keep them balanced. 

Fully grown Gorgosaurus had length from its snout to tail reaching 8 to 9 meters (26 to 30 ft).

Gage Beasley Prehistoric's Gorgosaurus Size Comparison Chart
Gage Beasley Prehistoric’s Gorgosaurus Size Comparison Chart

Adults were also bulkier than other similar lizards of their size, and had a large weight between 2 to 3 metric tons (2.2 to 3.3 tons).

The longest femur from Gorgosaurus measured at 105 cm (41 in.), and their tibia is typically measured the same length as their femur.

In some specimens the tibia of Gorgosaurus has measured longer than their femur, which is a trait associated with speedy animals. 

Gorgosaurus had an elongated skull and their snout was blunt, with the largest skull fossil ever found measuring around 99 cm (39 in.) long.

On their skull from their lacrimal bone Gorgosaurus had crests, or small horn protrusions that rose above each of their eyes. 

Hand-drawn representation of a Gorgosaurus head
Hand-drawn representation of a Gorgosaurus head | Utahraptor ostrommaysi via Wikimedia Commons CC A-SA 3.0

Gorgosaurus teeth were similar to other tyrannosaurids, and their large mouths contained eight premaxillary teeth, 26 to 30 maxillary teeth, and 30 to 34 teeth in their lower jaw. 

Fossils preserved of these dinosaurs showed they had scaly skin, but their scales were large, and hexagonal, similar to modern animals like the beaded lizard. 

The Albertosaurus is a dinosaur very similar to the Gorgosaurus, and in the past these two dinosaurs have been confused with each other. 

The Albertosaurus had a similar build, and crests above their eyes, but the shape of their bone structure surrounding their brains is how these two dinosaurs have been differentiated. 

Habitat and Distribution

Gorgosaurus lived in North America during the Late Cretaceous period around 80 to 73 million years ago.

The majority of fossil specimens from Gorgosaurus have been found in the Dinosaur Park Formation in Alberta Canada.

Fossils from this species have also been found in formations within Montana.

North America during the Cretaceous period was a very different environment than today, and the continent was separated into two large land masses, separated by the large waterway that was the Western Interior Sea.

Along with having lots of floodplains, rivers, and coastal regions, the western interior seaway made the environment that Gorgosaurus lived in very moist.

The climate of North America during the Late Cretaceous was subtropical, with seasonal periods of drought. 

Large conifer forest at Eastern France
Large conifer forest at Eastern France | Sapin88 via Wikipedia CC BY-SA 3.0

Plants that lived alongside this dinosaur include ferns, angiosperms, conifers, cycads, and ginkgoes.

Most of Gorgosaurus fossils have been found in Alberta, so it is believed this is where this dinosaur mainly lived. 

Behavior and Diet

Gorgosaurus was a carnivorous dinosaur that preyed on other dinosaurs, mainly plant eating ones. 

This dinosaur was an apex predator in its range, with very few dinosaurs able to challenge them.

Plant eating dinosaurs like the Centrosaurus, Corythosaurus, and Lambeosaurus are the types of dinosaurs that Gorogosaurus hunted the most. 

Gorgosaurus used their sharp teeth and large mouths to kill their prey. 

Life restoration of Gorgosaurus
Life restoration of Gorgosaurus | Johnson Mortimer via Wikimedia Commons CCA 3.0

The bite force of Gorgosaurus has been studied using the fossils left behind and it is estimated this dinosaur could produce a force between 22,000 to 42,000 newtons. 

It is also estimated that the Gorgosaurus was able to run a top speed between 40 to 48 km/h. (25 to 30 mph), which helped them chase down their prey. 

The serrated teeth, speed, keen eyesight, and powerful bites of the Gorgosaurus made them top predators in their environment, and they were experts at ambushing, and taking down their prey. 

It is possible that due to their size Gorgosaurus could have eaten other theropods, or even may have experienced cannibalism, but this would have been rare. 

Hunting in packs has been theorized for dinosaurs like Gorgosaurus, and other Tyrannosaurids, but this is still heavily debated. 

If Gorgosaurus did hunt in packs it would have allowed them to  take down large prey easier, and work together to increase their hunting success rate. 

Gorgosaurus is a genus of tyrannosaurid dinosaur that lived during the late Cretaceous period
Gorgosaurus is a genus of tyrannosaurid dinosaur that lived during the late Cretaceous period | Levi Bernardo via Wikimedia Commons CC A-SA 3.0

Fossils of Gorgosaurus specimens being discovered together supports the theory they had gregarious behavior, but there is still much research to be done to confirm this. 

Life Cycle

By studying the fossils of Gorgosaurus, and using their bone histology, scientists have been able to learn much about these dinosaur’s growth when compared with other genus.

Gorgosaurus spent around half of their lives in their juvenile phase, before experiencing an extreme growth rate, which would slow down in their adulthood.

The maximum growth rate of Gorgosaurus occurred at around 5 to 7 years old, and they would gain about 50 kgs (110 lbs.) of mass a year until they reached maturity. 

The growth rate of Gorgosaurus was slower than other dinosaurs like Daspletosuarus, and Tyrannosaurus, but similar to a very similar species the Albertosaurus

While not nearly as powerful as their adult forms, juveniles of Gorgosaurus were much quicker, using their speed to take down prey. 

A profile view of Gorgosaurus
A profile view of Gorgosaurus | Sphenaphinae via Wikimedia Commons CC A-SA 4.0

Younger Gorgosaurus filled in the predatory niche that larger ones could not, but these dinosaurs despite their smaller size did not have many predators since they had the ability to outspeed larger carnivores. 

The lifespan of Gorgosaurus is still unknown, but if similar to other large Tyrannosaurids they could have lived up to 30 years, but would have had an average lifespan of around 14 years. 

Gorgosaurus like other dinosaurs reproduced by using eggs, and they likely watched their young until they were able to fend for themselves. 

The horns of this dinosaur’s eyes are theorized to be used for courting, and mating, since they would have been too small to be used for fighting. 

There is still much to learn about this dinosaur’s lifecycle, which may come in the future with further studies, and discoveries. 

Evolution and History

Gorgosaurus was described in 1914, by Lawrence Lambe, and this dinosaur’s holotype was found in 1913, by Charles M. Sternberg in the Dinosaur Park Formation in Alberta, Canada. 

This bipedal predator may have been covered in scales or perhaps feathers
This bipedal predator may have been covered in scales or perhaps feathers | Leoomas via Wikimedia Commons CC A-SA 4.0

Gorgosaurus libratus is the type species, and their genus name translates to “dreadful lizard” in Greek, while their species name means “to balance” in Latin.

The discovery of Gorgosaurus was that of a nearly complete specimen, and this dinosaur was also the first Tyrannosaurid to be found with a complete hand. 

While the majority of fossils from Gorgosaurus have been discovered in the Dinosaur Park Formation, there have been several specimens found in Two Medicine, and Judith River Formation in Montana that likely belonged to Gorgosaurus

There have been several synonyms of Gorgosaurus that are currently not valid, which includes species, and other genus.

Former species like Gorgosaurus lancensis were described by using a complete skull of a small tyrannosaurid, but this was later discovered to be a juvenile Tyrannosaurus rex

Tyrannosuarids can appear very similar, especially in places like their teeth which can look nearly identical with one another, and some genus only have very small differences between their fossils.

Life reconstruction of Albertosaurus
Life reconstruction of Albertosaurus | Nobu Tamura via Wikimedia Commons CC A-SA 4.0

The Gorgosaurus is a member of the subfamily Albertosaurinae, and is believed to be closely related to the Albertosaurus.

With more fossil evidence in the future, how these dinosaurs evolved over time, and their relation with species like the Albertosaurus may become more clear. 

Interactions with Other Species

The Gorgosaurus was an apex predator in its environment, and even when young this dinosaur used its strength, and speed to remain at the top of its food chain. 

There were also other Tyrannosaurids that Gorgosaurus lived alongside, which include Daspletosaurus, but this genus was much more rare.

Daspletosaurus was a more heavily built dinosaur, but it is not believed they hunted Gorgosaurus since they would have been slower. 

While the range of these two Tyrannosuarids did overlap, Daspletosaurus was more common in the southern regions of North America, while Gorgosaurus ruled the north. 

Skeleton of Gorgosaurus at the Royal Tyrell Museum
Skeleton of Gorgosaurus at the Royal Tyrell Museum | Sebastian Bergmann via Wikimedia Commons CC A-SA 2.0

The abundance of Gorgosaurus fossils suggest these dinosaurs were better adapted for their environment, and were the dominant dinosaur when compared with the Daspletosaurus

Other dinosaurs like anklyosaurians, pterosaurs, oviraptorosaurs, dromaeosaurs, and ornithomimids also lived alongside Gorgosaurus.

The Gorgosaurus was a very aggressive dinosaur, and preyed on any animal they were able to catch, and very few animals were able to challenge them.

There have been markings and damage found on Gorgosaurus fossils suggesting it was common for these dinosaurs to fight amongst each other. 

Gorgosaurus was very aggressive, and attacked animals from prey, to members of their own species. 

Cultural Significance

Gorgosaurus is a very important dinosaur, since it is one of the few Tyrannosaurids that have been found with fossils showcasing multiple stages in their life.

Digital drawing of Gorgosaurus, a theropod from the Late Cretaceous of North America
Digital drawing of Gorgosaurus, a theropod from the Late Cretaceous of North America | Arthur Weasley via Wikimedia Commons CCA 2.5

This dinosaur has been crucial in understanding the Tyrannosaurid family, and how these dinosaurs evolved overtime before going extinct. 

Gorgosaurus fossils have been very abundant, with many of them nearly complete.

The fossils from this dinosaur have allowed studies not capable with dinosaurs that have less specimens discovered.

The abundance of Gorgosaurus fossils have allowed this species to be showcased in museums around the globe for people to enjoy.

These dinosaurs have also been put in games like Jurassic Park, and they are loved for their size and ferocity. 

Gorgosaurus is one of the many Tyrannosaurids that we know of, and this species has been essential in uncovering the mysteries of these dinosaurs. 


Gorgosaurus lived during the Late Cretaceous period around 83 to 66 million years ago in what is now North America, and were one of the most dominant land predators to walk the earth.

Tyrannosaurids like Gorgosaurus are one of the most loved types of dinosaurs due to their size, large teeth, and aggressive predatory dominance.

While they look like creatures of fiction, Gorgosaurus is known from the many fossils they left behind, which have helped uncover several mysteries about these dinosaurs, and their relatives. 

Dinosaurs are always being studied, and as more evidence from the past emerges from the earth’s ground, there may be more interesting things learned about the Gorgosaurus, and the prehistoric environment they lived in. 


Did Gorgosaurus have feathers?

Fossils from Gorgosaurus have shown no signs they had feathers, and these dinosaurs are only known to have smooth scaly skin, with large scales. 

How expensive is a Gorgosaurus fossil?

Gorgosaurus has been one of the few fossils that have been sold in auction, and in 2022 a skeleton of this giant sold for a bit over $6 million. 

What caused Gorgosaurus to go extinct?

It is not known exactly what caused the Gorgosaurus to go extinct, but it is believed they went extinct before the end of the Cretaceous period.

Competition with other similar dinosaurs is likely what caused this dinosaur to go extinct, while some believe the asteroid impact in North America killed this genus off with the rest of the dinosaurs.


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