# Pachycephalosaurus (*Pachycephalosaurus wyomingensis*)

Pachycephalosaurus was a prehistoric dinosaur known for its distinctive features. Scientists study its bones to learn about how dinosaurs lived.

- **Category:** [Ancient](https://www.snappit.app/explore/categories/ancient)
- **Rarity:** Common
- **Danger:** 1/5 · Very low
- **Habitat:** Mesozoic forests and floodplains
- **Also known as:** Thick-headed Lizard

![Pachycephalosaurus](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Pachycephalosaurus_Reconstruction.jpg&width=800)

Photo: Fred Wierum, CC BY 4.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Pachycephalosaurus_Reconstruction.jpg)

## Appearance

The Pachycephalosaurus is a bipedal dinosaur defined by its enormous, bony dome-shaped skull, up to 10 inches thick. It had a relatively short, thick neck and a spiky fringe around the base of its dome, with small horn-like bumps on its snout.

## Taxonomy

- **Kingdom:** Animalia

## Interesting facts

- Its super thick skull was almost 10 inches deep!
- Pachycephalosaurus means 'thick-headed lizard' in Greek!
- Scientists found its fossils only in North America!
- They might have used their domes for head-butting contests!

## Special abilities

- **Dome Defender:** Pachycephalosaurus has an incredibly thick, bony skull that helps them protect their brain or impress rivals.
- **Head-Butt Hurler:** Pachycephalosaurus can charge at great speed because of their strong legs and sturdy dome for defense or display.
- **Speedy Scrambler:** Pachycephalosaurus can move quickly on two powerful legs that helps them escape from fast predators.

## Measurements & details

- **Length:** 4.5-5 m
- **Weight:** 400-475 kg
- **Era:** Late Cretaceous Period
- **Extinct Millions Years Ago:** 66

## Diet & Feeding

This plant-eating dinosaur nibbled on leaves, fruits, and seeds from low-growing plants.

- **Primary Foods:** Ferns, Cycads, Flowering plant leaves, Fruits, Seeds
- **Foraging Method:** Foraging

## Ecological connections

- **Eaten by:** [Tyrannosaurus rex](https://www.snappit.app/explore/tyrannosaurus-rex) (*Tyrannosaurus rex*) — Apex predator in its habitat.
- **Eaten by:** Dakotaraptor (*Dakotaraptor steini*) — Large raptor that might have preyed on juveniles.
- **Depends on:** Ancient Sycamore Tree (*Platanus nobilis*) — A source of various leaves and buds.

## Traits

- [Ancient](https://www.snappit.app/explore/traits/ancient): Ancient refers to organisms, objects, or geological formations that have existed for an extremely long period.
- [Artifact](https://www.snappit.app/explore/traits/artifact): An artifact is an object made or modified by human culture, typically of historical or archaeological interest.
- [Fossil](https://www.snappit.app/explore/traits/fossil): A fossil is the preserved remains or traces of an ancient organism embedded in rock or other geological deposits.

## Collections

- [Ancient](https://www.snappit.app/explore/collections/ancient)

## Safety

**Danger:** 1/5 · Very low

While extremely dangerous in their time, this creature is now extinct.

## Frequently Asked Questions

### How to identify Pachycephalosaurus?

Compare skull shape, horns, plates, limbs, posture and tail. Museum models and toys can mix features or follow outdated reconstructions. Dinosaur Identifier: upload a photo and compare the visible details.

### How long is Pachycephalosaurus?

4.5-5 m

### How much does Pachycephalosaurus weigh?

400-475 kg

### What does Pachycephalosaurus eat?

This plant-eating dinosaur nibbled on leaves, fruits, and seeds from low-growing plants.

### Where is Pachycephalosaurus usually found?

Mesozoic forests and floodplains

### How does Pachycephalosaurus hunt?

Foraging

### What geologic era did Pachycephalosaurus live in?

Late Cretaceous Period

### When did Pachycephalosaurus go extinct?

66

## More Ancient

- [Tyrannosaurus rex](https://www.snappit.app/explore/tyrannosaurus-rex) (*Tyrannosaurus rex*)
- [Triceratops](https://www.snappit.app/explore/triceratops) (*Triceratops horridus*)
- [Stegosaurus](https://www.snappit.app/explore/stegosaurus) (*Stegosaurus stenops*)
- [Brachiosaurus](https://www.snappit.app/explore/brachiosaurus) (*Brachiosaurus altithorax*)

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Source: [Pachycephalosaurus: Facts & Places to See — Snappit](https://www.snappit.app/explore/pachycephalosaurus)