The Ankylosaurus is one of the most interesting dinosaurs that have ever existed. The reason is simple: the impressive armor that covered it. In fact, it is considered the most relevant armoured specimen.

This dinosaur had a natural armor that made it a walking tank. Proof of this is its own name, Ankylosaurus means, in Greek, “armored lizard.

But that’s not all, this Ankylosaurus had a terrible secret weapon.

A weapon so devastating that in a hypothetical fight against a Tyrannosaurus rex, our Ankylosaurus would most likely beat it to a pulp.

I’m sure after reading that you’ll be eager to know more. Don’t worry, today in we tell you everything about the Ankylosaurus: the devastating tank dinosaur.

The family: Ankylosaurs

Your family tree (classification) is as follows:

  • The Ankylosaurs (Ankylosauria)
  • Ankylosaurids (Ankylosauridae)*
  • Within the same group (as if it were a sibling relationship) is the Euoplocephalus (“well-armed head” in Greek)

There is no unanimity among paleontologists that Ankylosaurus belongs to this subfamily.


  • SPECIE ANKYLOSAURUS magniventris

The Ankylosaurs (Ankylosauria) were a family of strong, armored dinosaurs. Some of the specimens in this family were very surprising.

For example, the Sauropelta which had huge spikes or nails sticking out of its neck. This family of dinosaurs lived all over the planet, except in Africa.

Where and when did this ankylosaur live

To tell you that he lived; day up, day down, about 68 million years ago.

This moment is called the Upper Cretaceous period, specifically in the Maastrichtian. This stage is the last one before the dinosaurs disappear.

Therefore, our friend was one of the species that survived until the fall of a meteorite caused the extinction of all dinosaurs.

The ankylosaurs in North America

The Ankylosaurus is, together with its brother Euoplocephalus, the only member of this family that lived in North America.

The rest of the species lived in East Asia.

You may wonder how it is possible that they lived in such a remote place from the rest of its members.

The answer is provided by the history of the earth itself.

Some 200 million years ago, the earth’s map was quite different from what it is today.

At that time, there were not five continents as there are today, but two: Laurasia and Gondwana.

Laurasia was the northern continent and included North America, Europe and Asia. The southern continent, Gondwana, was South America, Africa, Australia, the Hindustan peninsula, the island of Madagascar, and Antarctica.

Therefore, North America and Asia were united, there were no oceans to separate them.

It can be seen that at that time, the great-great-grandparents of Ankylosaurus crossed from Asia to America.

To be more precise, remains of the “armoured lizard” have been found in Montana and Wyoming (western USA) and Alberta (Canada).

To this day, not a whole skeleton of the lizard has been found.

Who discovered this dinosaur?

So to speak, this Ankylosaurus was named by Barnum Brown in 1908.

I don’t mean by this that it was the first time that remains of this species were found. Remains had already been found two years earlier. The same paleontologist, Brown, had discovered some pieces in Montana.

He didn’t claim the name until 1908 because previous finds had been attributed to other dinosaurs. It is said that at first, Brown attributed the name of Dynamosaurus.

In that year, what he found was a part of a skull, vertebrae, ribs and, of course, the armor. The discovery showed that they were in error and that what they had before them was a new species of dinosaur.

But they still had to wait two more years for the full morphology of this ankylosaur to be revealed.

At that time, Barnum Brown himself again found another Ankylosaurus in Alberta, Canada. The value of this finding was that for the first time the caudal sledgehammer was found.

Do you remember that at first I mentioned that the Ankylosaurus had a powerful secret weapon?
I was referring to the caudal sledgehammer. It was a bulge at the end of its tail with which it could strike its enemies.

The specimens Brown found are on display at the New York Museum of Natural History. Also, in Canada, at the Canadian Museum of Nature, the largest skull found is on display. This rest was also found in Alberta, in 1947, although this time the discovery was made by Charles M. Sternberg.

This American paleontologist, Barnum Brown, was also the discoverer of Tyrannosaurus rex.
His way of dressing was very characteristic since it was not strange to see him dressed in a beaver coat up to the knee. With a matching hat, of course.

His second wife, Lillian, wrote a book of memoirs dedicated to her husband’s findings. It was entitled “I Married a Dinosaur.”

What Ankylosaurus was like: characteristics

  • Name Ankylosaurus
  • Length Between 8 and 9 meters approx.
  • Height 1.8 meters
  • Weight Between 5 and 6 tons
  • Herbivore Diet
  • Upper Cretaceous or Tertiary Period

As you can see, it is between 8 and 9 metres long.
If we put the Ankylosaurus on a scale, it would tell us that it weighs about 6 tons. This makes it the largest ankylosaur known. To give you an idea, an African elephant weighs between six and seven tonnes.

However, a reconstruction made in function based on the largest skull found (the one discovered in Canada by Stenberg).

This simulation suggests a much smaller size: about 6.25 meters long and 1.5 meters wide.

This dinosaur was a quadruped. Its body (which is also why it reminds us of a tank) was low and quite wide. As low as it was, its back legs were longer than its front ones.

Although there is no certainty, as no limb has ever been found, it is believed that it had five toes on each leg. This possibility is pointed out because other members of the ankylosaurids had them.

His head was shaped like a triangle and was wider than long.

A rather characteristic feature of this dinosaur is its teeth. They’re very peculiar given their small size. Despite being the largest ankylosaurid, proportionally, its teeth are the tiniest.

Another abnormally small spot on this dinosaur was its brain. In fact, this ankylosaur is often attributed with a rather low intelligence.

A bulletproof armour

However, the most characteristic feature of Ankylosaurus is its bone armor.

From head to tail, this dinosaur was covered by plates of welded bone.

These plates, arranged, one after the other, in horizontal lines, cover its entire body. Also, the sides of the body and the head

In this way, its head was very well protected.

These plates, called osteoderms, were of different sizes. So they could adapt to the different areas of the animal. In fact, to improve its defense, some of these osteoderms were shaped like balls.

These balls were placed between the large plates to reinforce the structure of the armor. This made it more compact and more difficult to break.

Another point that reinforced this solid and rigid shape was that the bones in the skull and other parts of the body were also fused together.

To further strengthen the defensive security of the armor, the entire armor was topped off with sharp spikes and bulges. As with the body, its head was topped by four horns.

Her entire breastplate was covered with a thick layer of keratin. This material is what your fingernails are made of.

This kind of armour can still be seen on some modern animals. For example: in crocodiles, armadillos and some kind of lizard. Another curious thing, but this time from his brother, the Euoplocephalus, are his eyes. These were also protected by osteoderms.

The caudal sledgehammer

This ankylosaur’s secret weapon.

This sledgehammer was formed at the end of its tail. Its origin is due to the fusion of the last caudal vertebrae.

One of the discoveries that pointed to the use of this mallet as a weapon was that tendons were found in it. This showed that he could swing it, so that with the impulse he would have more strength.

What this type of dinosaur eats

The Ankylosaurus was an herbivore, in other words, it only ate plants.

In fact, its tiny teeth were optimised for this. They were shaped in the perfect way to cut the leaves it ate.

However, this ankylosaur did not have any grinding teeth, so it is believed that it did not chew much.

In fact, scientists believe that because it could not chew much, it swallowed stones to aid digestion.

This dinosaur lived near forests near rivers. Always inland, as the vegetation near the sea is too hard for its jaw.

How this ankylosaurid behaved

The Ankylosaurus was a solitary animal, since thanks to its shell it was not afraid of other predators.

They did, however, gather once a year for mating.

The males would fight each other with their sledgehammers until one of them withdrew.

It is also said, that in addition to fighting, the size of the tailstock could be used to attract females.

Ankylosaurus vs T. Rex

Imagine the fight. A tank dinosaur against one of the biggest predators known – Tyrannosaurus rex.

The battle strategy of our Ankylosaurus is clear. Its greatest potential lies in its stamina, its defence and its great armour.

With its armor, no matter how much the Tyrannosaurus rex bit or hit him, it could not handle him. At least not without much difficulty.

When our ankylosaur was attacked by a carnivorous predator, it tended to hide its legs under the body. Don’t forget that his head was also protected by osteoderms.

In that position, it became a devastating block that could resist the blows and bites of its enemies. If you think about it, it’s the same technique that turtles use when they hide in their shell.

But of course, the difference is that Ankylosaurus is almost the size of a bus, so, protected behind its shell, it was almost indestructible.

With its short legs and its weight, this ankylosaur was slow. It couldn’t run very fast, so in a fight, running away was not a great option.

Sometimes, there’s no better defence than a good attack.

Despite its slowness, it was a fairly agile dinosaur. The fact that his hind legs were longer favoured him in this respect. It could dodge its attackers and turn to attack.

His attack consisted of raising his heavy mallet and swinging it to gain more strength from the power of inertia. This was evidenced by finding tendons in the remnants of a tailgun.

Although it is known that bipedal predators were terrible, one need only think of a Tyrannosaurus rex. If it was hit by an Ankylosaurus, it would most likely go wrong.

With a single blow from its sledgehammer, it could break either its rib bones or its legs. If he broke one, the predator would fall to the ground and be at the mercy of other animals.

Don’t forget that Ankylosaurus was an herbivore.

However, this ankylosaurid was not invincible, it had a weakness.

Its armor did not completely cover it, its belly was not protected. Therefore, if a predator managed to turn it over, it was already very easy to beat it.

The Ankylosaurus in Jurassic Park and in the movies

As we commented at the beginning, this ankylosaur is a very interesting dinosaur and also very peculiar.

This has led it to appear in several movies, series or video games.

A life-size representation can be seen at the 1964 World’s Fair in New York.

An Ankylosaurus was one of Godzilla’s main enemies. We refer to the film Godzilla Raids Again.

In the cartoon film, “In Search of the Enchanted Valley”, this Ankylosaurus appears several times. Also, it is seen in the later films of the saga.

In the most famous dinosaur movie Jurassic Park, we can also find him. But it wouldn’t be in the early movies, it would be in Jurassic World.

In fact, not only is he seen, but as we recreated before, you can see him fighting against Induminus rex (female fictional dinosaur, very similar to Tyrannosaurus rex)

In this scene, we see four ankylosaurs grazing peacefully. The two boys are in the gyrosphere talking when the Induminus Rex arrives. At that moment the battle begins, in the scene you can see how the Ankylosaurus uses its caudal sledgehammer to attack the predator.