Fun Acrotholus Facts For Kids

Oluniyi Akande
Oct 20, 2022 By Oluniyi Akande
Originally Published on Feb 11, 2022
Edited by Jacob Fitzbright
Fact-checked by Gowri Rao
Dinosaurs in the valley

Acrotholus was a very interesting dinosaur. This specimen was a type of ornithischian dinosaur that dwelled on Earth during the Santonian age, in the late Cretaceous period.

The fossils of this animal were first discovered in the North American Milk River Formation, situated in Alberta, Canada. The best fossil bones of this dinosaur were found at the land of a rancher named Rou Audet.

Talking about its diet, herbivorous animals like the Acrotholus would have depended on the flora and natural vegetation which would have thrived at that time. This dinosaur of the Santonian age is said to be the earliest known member of the Pachycephalosaur family, making the discovery of their fossils a very important one.

A fully complete skeleton of the Acrotholus is not known yet. Only the skull has been derived.

It was in the year 2013 when David C Evans described the species. The skull of this dinosaur had a high dome, making it a very fun dinosaur to know about.

Acrotholus Interesting Facts

How do you pronounce 'Acrotholus'?

The name 'Acrotholus' is pronounced as 'ACK-roe-THO-luss' (æk-roʊ-θɔ-ləs).

What type of dinosaur was an Acrotholus?

This North American dinosaur is a type of ornithischian dinosaur, belonging to the family Pachycephalosauridae.

In which geological period did the Acrotholus roam the Earth?

This Pachycephalosaurid roamed the Earth during theSantonian stage of the Late Cretaceous era.

When did the Acrotholus become extinct?

It is said that these Pachycephalosaurs existed up to 85 million years ago.

Where did an Acrotholus live?

The holotype of the Acrotholus fossil was discovered in the Deadhorse Coulee Member at the Milk River Formation situated in Southern Alberta of Canada.

What was an Acrotholus's habitat?

Researchers found out that this dinosaur species frequently occupied coastal areas, even though they had a terrestrial lifestyle. They lived close to coastal plains and floodplains. Analysis of the hindlimb portions has shown similarities to wading birds which are known to inhabit wetland areas.

Who did an Acrotholus live with?

We are not aware of who this Pachycephalosaurid of North America lived with.

How long did an Acrotholus live?

We do not know the lifespan of the North American Acrotholus audeti.

How did they reproduce?

We do not know the reproductive behavior of this Pachycephalosaurid specimen from the fossil records found. However, it is assumed that they would have had similar breeding habits to other dinosaurs of their time, and laid eggs as a means of reproduction.

Acrotholus Fun Facts

What did an Acrotholus look like?

The discovery of a fully complete Acrotholus skeleton has not been made.

The Acrotholus skull is in the shape of a dome. This dome is oval in shape.

The skull has a thickness of about 2.2 in (5.5 cm) above the cerebral fossa. The fossil retrieved lacked tubercles and tesserae, which was an indication that the retrieved fossil was not of a juvenile. CT scans conducted on the dome-shaped skull showed that there were high density, low vascularity internally fused frontal-parietal and frontal-frontal sutures.

The peripheral bones of the thick skull of Acrotholus audeti are situated high and are well developed. The orbital fosse of the skull is slightly concave, which is pierced by small foramina.

The dorsally convex frontonasal boss has been concluded to be short, without any separation by grooves from the anterior supraorbital lobe. On the ventral side of the frontal-parietal dome, three depressions are observed - the temporal fossa, the endocranial fossa, and the orbital cavity.

It is thought that this species had a small body size.

*We've been unable to source an image of Acrotholus and have used an image of a Pachycephalosaur instead. If you are able to provide us with a royalty-free image of Acrotholus, we would be happy to credit you. Please contact us at


How many bones did an Acrotholus have?

Unfortunately, we are not aware of this information solely on the basis of the fossil records available.

How did they communicate?

Though we cannot guarantee their mean of communication, we think these animals probably conveyed information visually and vocally.

How big was an Acrotholus?

It has been estimated that these Pachycephalosaurs were around 6 ft (1.828 m) long.

This makes them more than three times the size of the Archaeoceratops yujingziensis.

How fast could an Acrotholus move?

Sorry, we do not have information on the speed of these Pachycephalosaurs of the late Cretaceous period.

How much did an Acrotholus weigh?

From the fossil records, it can be suggested that the Acrotholus audeti weighed around 88 lb (40 kg).

What were the male and female names of the species?

There are no separate sex-specific names for the male and female dinosaurs of this species.

What would you call a baby Acrotholus?

Baby dinosaurs that hatch from eggs are called hatchlings.

What did they eat?

This high dome-headed dinosaur is a primary herbivore in its diet. The possible source of food for this dinosaur was the flora in its habitat. There is no complete information available on the diet of this species. The research on the diet has been developed through the bones of the skull.

How aggressive were they?

We are not aware of the aggression of this dome-headed Pachycephalosaurs species.

Did you know...

The Milk River Formation has been the discovery point of many other species of the late Cretaceous period. Some of these include the Alphadon and the dinosaur Saurornitholestes.

If the discovery of fossils of dinosaurs is made on someone's land, it is important to seek their permission to gain access and conduct scientific research, just like how Alberta rancher Roy Audet did.

Some of the famous dinosaurs discovered in Alberta, Canada include Albertosaurus, Albertavenator curriei, Chasmosaurus, crested Edmontosaurus, Stegocerasm Gorgosaurus, and Pachyrhinosaurus Lakustai.

Other well-known dinosaurs whose fossils were discovered in the history of Canada include Parasaurolophus, Dromaeosaurus, Centrosaurus, Corythosaurus, Pachyrhinosaurus, Lambeosaurus, and Styracosaurus.

Based on their diet, herbivore dinosaurs include Triceratops, Moschops, Diplodocus, Ankylosaurus and Nodosaurus.

Other dinosaurs known to have a dome skull include Prenocephale prenes, Hanssuesia sternbergi, Tylocephale gilmorei, Foraminacephale, Sphaerotholus goodwini, Sphaerotholus buchholtzae, Alaskacephale gangloffi, Amtocephale gobiensis, Homalocephale calathocercos, Goyocephale lattimorei, and Hanssuesia sternbergi.

Acrotholus audeti is discovered to be a sister taxon to dinosaurs like Wannanosaurus yansiensis, Colepiocephale lambei, and Prenocephale prenes.

Certain research suggests that the Tyrannosaurus Rex had the strongest skull of all dinosaurs. This skull was thick and heavy.

The Acrotholus may have been hunted down by smaller, dangerous predators like the Richardoestesia or the Saurornitholestes. The fossils of these animals have been found at the Milk River Formation of Canada.

Canadian paleontologist David Christopher Evans has been involved in naming ceratopsians such as Xenoceratops foremostensis, Gryphoceratops morrisoni, Unescoceratops koppelhusi, Mercuriceratops gemini, Wendiceratops pinhorensis, Spiclypeus shipporum, and Ferrisaurus sustutensis.

David C Evans has also been a part of the team which has named ornithopods such as Albertadromeus syntarsus, Plesiohadros djadokhtaensis, and Gobihadros mongoliensis.

Evans currently holds the position as the Senior Curator as well as the Temerty Chair of the Vertebrate Paleontology Department at Toronto's famous museum, the Royal Ontario Museum.

How did the Acrotholus protect itself?

Unfortunately, we are not aware of how this dome-headed dinosaur species of North America protected itself. Maybe it would attack possible predators with its thick skull. However, there are no solid claims on such head-bashing theory of the late Cretaceous era.

How did the Acrotholus get its name?

Acrotholus in Greek translates to 'the highest dome'. This comes from the Greek terms 'akros', meaning 'highest', and 'tholos', meaning 'dome'. This is in reference to the high dome-shaped head of this Pachycephalosaur.

The species name of this Pachycephalosaur, 'audeti', is in the honor of Roy Audet, an Alberta rancher. It was on the land of Roy Audet that the best specimen of this Ornithischian species was discovered in the year 2008. This dinosaur was described by David C Evans in the year 2013.

Main image by Nobu Tamura.

Second image by DataBase Center for Life Science (DBCLS).

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Written by Oluniyi Akande

Doctorate specializing in Veterinary Medicine

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Oluniyi AkandeDoctorate specializing in Veterinary Medicine

With an accomplished background as a Veterinarian, SEO content writer, and public speaker, Oluniyi brings a wealth of skills and experience to his work. Holding a Doctor of Veterinary Medicine degree from the University of Ibadan, he provides exceptional consulting services to pet owners, animal farms, and agricultural establishments. Oluniyi's impressive writing career spans over five years, during which he has produced over 5000 high-quality short- and long-form pieces of content. His versatility shines through as he tackles a diverse array of topics, including pets, real estate, sports, games, technology, landscaping, healthcare, cosmetics, personal loans, debt management, construction, and agriculture.

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Fact-checked by Gowri Rao

Bachelor of Arts specializing in Economics

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Gowri RaoBachelor of Arts specializing in Economics

With a bachelor's degree in Economics from Krea University, Gowri is a highly skilled data analyst and an expert in regression and causation modeling. Her interests in economic trends, finance, and investment research complement her professional expertise. In addition to her professional pursuits, Gowri enjoys swimming, running, and playing the drums, and she is also a talented tutor.

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