Gorgosaurus: The Fierce Predator of the Late Cretaceous

Gorgosaurus: The Fierce Predator of the Late Cretaceous

Gorgosaurus, a formidable carnivorous dinosaur, reigned during the Late Cretaceous Period, approximately 83.5 to 72.1 million years ago. Known for its powerful build and predatory prowess, this theropod has intrigued scientists since its discovery in the early 20th century. Its name, meaning ‘Dreadful Lizard’, aptly captures its role as a dominant force in the prehistoric ecosystems of what is now North America.

First unearthed in Alberta, Canada, by Charles Sternberg in 1913, Gorgosaurus has since been a subject of extensive study. The well-preserved fossils provide a window into the life of this impressive dinosaur, offering insights into its physical characteristics, behavior, and the environment it inhabited.

Gorgosaurus Key Facts

Meaning of name‘Dreadful Lizard’
Type SpeciesGorgosaurus libratus
When it Lived83.5 to 72.1 MYA
PeriodLate Cretaceous
Length26.0 to 30.0 feet
HeightApproximately 8.2 feet at hips
Weight2.2 to 3.3 tons
MobilityMoved on two legs
First Discovery1913 by Charles Sternberg
Described by1914 by Lawrence Lambe
HolotypeNMC 2120
Location of first findAlberta, Canada
Also found inMontana, USA

Gorgosaurus Origins, Taxonomy and Timeline

Gorgosaurus, whose name derives from the Greek ‘gorgos’, meaning fierce or terrible, and ‘saurus’, meaning reptile or lizard, is a testament to the awe-inspiring creatures that once inhabited our world. Its moniker is a fitting tribute to its formidable nature, a carnivorous beast that undoubtedly instilled dread in the hearts of its contemporaries.

Gorgosaurus libratus, a theropod from the late Cretaceous of North America, pencil drawing & digital coloring
Nobu Tamura, CC BY-SA 3.0, via Wikimedia Commons

Belonging to the Theropoda, this dinosaur is classified within the tyrannosaurid, a lineage known for producing some of the most fearsome predators to have ever walked the Earth. Gorgosaurus libratus, its type species, represents a pinnacle of predatory evolution within this distinguished family.

The timeline of Gorgosaurus spans a significant portion of the Late Cretaceous Period, during the Campanian. This places it in a world approximately 83.5 to 72.1 million years ago, a time when dinosaurs were the dominant terrestrial vertebrates.

Discovery & Fossil Evidence

The discovery of Gorgosaurus libratus, a species first described by Lawrence Lambe in 1914, marked a significant milestone in paleontological history.

A nearly complete skeleton, NMC 2120, along with its associated skull, was unearthed in 1913 by Charles Sternberg in the Dinosaur Park Formation of Alberta. The significance of this find was further underscored by the simultaneous efforts of prospectors from the American Museum of Natural History, who were excavating along the Red Deer River. Their endeavors yielded four complete G. libratus skulls and three skeletons, enriching the fossil record and providing a broader context for understanding the species’ anatomy and behavior.

Among the specimens collected, AMNH 5458 stands out for its unique characteristics. Also discovered by Charles Sternberg, but in 1917, this specimen exhibited a smaller stature, a lighter skull, and elongated limb proportions. These features were initially attributed to a new species, G. sternbergi, by Matthew and Brown in 1923. However, contemporary paleontology recognizes these traits as indicative of a juvenile G. libratus, offering a rare glimpse into the growth and development of tyrannosaurids.

Finds from other locations

The fossil record of Gorgosaurus extends beyond the borders of Alberta. Specimens from the Judith River Formation in Montana, housed in various institutions including the Children’s Museum of Indianapolis, have expanded the known range of this dinosaur. These Montana specimens, while not definitively classified, exhibit fascinating pathologies that speak to the resilience and survival of Gorgosaurus individuals. From healed fractures to infections and possible brain tumors, these fossils provide a narrative of survival against the odds, further cementing Gorgosaurus libratus as one of the most well-documented tyrannosaurids in paleontological research.

Gorgosaurus Size and Description

Gorgosaurus, a notable member of the tyrannosaurid family, was a quintessential predator of its era. Its physical attributes, honed over millions of years, were a testament to its role as a dominant carnivore. This dinosaur’s general body plan shared commonalities with other tyrannosaurids, yet it possessed unique features that distinguished it from its colossal cousins, painting a vivid picture of diversity within this group of fearsome predators.

Size and Weight of Type Species

Size comparison of Gorgosaurus libratus specimens NMC 2120 (adult) and TMP 91.36.500 (subadult).
Slate Weasel, CC0, via Wikimedia Commons

Gorgosaurus was not the largest of its kin but was formidable nonetheless. Adults could reach lengths of 26.0 to 30.0 feet, with a robust build that supported a weight of 2.2 to 3.3 tons. The skull, a critical component of its hunting arsenal, was slightly smaller than that of Daspletosaurus, measuring up to 39.0 inches long. These dimensions contributed to a powerful physique capable of overpowering the herbivores of its time. The dental arrangement was equally impressive, with a combination of smaller, D-shaped premaxillary teeth at the front and larger, oval-shaped maxillary teeth, amounting to a total that rivaled its relatives. This dental diversity was not just for show—it was a key factor in Gorgosaurus’s ability to process a variety of prey, ensuring its success as a top predator.

The Dinosaur in Detail

Gorgosaurus boasted a massive head anchored on an S-shaped neck, which allowed for a significant range of motion—a crucial adaptation for a hunter. The forelimbs, though small and bearing just two digits, may have been more functional than their size suggests, possibly used for grasping or stabilizing prey. The hindlimbs, complete with four digits including a non-weight-bearing first toe, were long and muscular, hinting at a creature capable of swift pursuit. The overall body structure of Gorgosaurus, with its large head and powerful legs, suggests an apex predator well-suited to the challenges of its environment.

Interesting Points about Gorgosaurus

Gorgosaurus in its Natural Habitat

Gorgosaurus thrived in an environment that was both challenging and rich with opportunities. The climate during its time was varied, with evidence suggesting a mix of lush forests and open plains. The geography of the Late Cretaceous was dynamic, with rising mountain ranges and receding seas shaping the landscape.

As a carnivore, Gorgosaurus was at the top of the food chain. Its diet likely consisted of large herbivorous dinosaurs, and its bipedal locomotion allowed it to chase down prey with lethal efficiency. Gorgosaurus’s role as a predator had a significant impact on the ecosystem, controlling the population of herbivores and possibly shaping the vegetation patterns through its hunting activities.

The social behavior of Gorgosaurus is a subject of ongoing debate, but evidence suggests it may have exhibited some level of social organization. Whether as solitary hunters or members of a pack, these dinosaurs were undoubtedly key players in their natural habitat, influencing the evolutionary path of other species around them.

Contemporary Dinosaurs

In the shadowy forests of the Late Cretaceous, Gorgosaurus, a towering predator with a bite as devastating as a wrecking ball, reigned supreme. It often found itself in a gritty contest with the Albertosaurus, its slightly smaller cousin. Both were tyrannosaurs, larger than a city bus, and their confrontations over territory were epic, shaking the ground beneath them as they vied for dominance.

ABelov2014, CC BY 3.0, via Wikimedia Commons

Gorgosaurus also had to consider Daspletosaurus, a contemporary of similar size but with a more robust frame. These encounters were tense, as each sought control over the best hunting grounds. Gorgosaurus, leaner and perhaps more agile, used its speed to outmaneuver this formidable rival, ensuring it didn’t lose its edge in the survival stakes.

Smaller but no less significant were Dromaeosaurus packs, nimble and sharp as Gorgosaurus’ own teeth. These smaller predators didn’t challenge Gorgosaurus directly for prey, but their cunning nature meant it had to be ever-watchful of these clever hunters that could turn from scavengers to competitors in a heartbeat.

And then there was Anodontosaurus, an armored herbivore that Gorgosaurus would eye cautiously. Smaller than our main dinosaur, Anodontosaurus was like a small tank, a challenge for any predator. Gorgosaurus may have been tempted by the prospect of a meal but knew that any attack would be a considerable undertaking. This dynamic underscored the complex interactions within their ecosystem, where not every encounter led to battle but rather a strategic game of survival. In this ancient world, Gorgosaurus navigated a delicate balance, asserting its role as a top predator in a land where size and intelligence were the currency of existence.

Frequently Asked Questions

What does the name of this dinosaur mean?

It means ‘Dreadful Lizard’, reflecting its fearsome nature as a top predator.

When was this dinosaur first discovered?

The first Gorgosaurus fossil was discovered in 1913 by Charles Sternberg.

What type of environment did it live in?

It lived in a varied environment with lush forests and open plains during the Late Cretaceous Period.

What did this dinosaur eat?

It was a carnivore.

How did it move around?

It was bipedal, moving on two legs, which allowed for swift locomotion.

What makes the fossils of this dinosaur significant?

The fossils, particularly the well-preserved holotype, provide valuable insights into its anatomy and lifestyle.


The information in this article is based on various sources, drawing on scientific research, fossil evidence, and expert analysis. The aim is to provide a comprehensive and accurate overview of Gorgosaurus. However, please be aware that our understanding of dinosaurs and their world is constantly evolving as new discoveries are made.

This article was last fact-checked: Joey Arboleda, 11-04-2023

Featured Image Credit: Levi bernardo, CC BY-SA 3.0, via Wikimedia Commons