Iguanodon

Say it: ig-WAH-noh-don

Name means: “iguana tooth”1

Ate: PlantsBeaked plant-eatersLate Jurassic to Late Cretaceous

Iguanodon was a big, plant-eating dinosaur that lived during the Early Cretaceous period. It had a thumb spike like a sharp weapon and a beak for snipping leaves. This dinosaur could walk on two legs or all fours.1 2

Lived

155 to 66 million years ago3

Late Jurassic to Late Cretaceous

Fossils found in

Belgium, Germany, England, Spain, and other parts of Europe, also North Africa, North America, Australia, and Asia1 2

Food

Plants1

Length

9 to 11 m1

Weight

4 tonnes to 5 tonnes1 2

Height

2 m2

at the hips

Artist's life restoration of Iguanodon — How Iguanodon may have looked, by Gideon Mantell. Public domain, via Wikimedia Commons. Scientists still argue about colours and details.

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

cool stuff

Fun facts

Iguanodon was named in 1825 by Gideon Mantell after he found teeth that looked like iguana teeth.1

Its thumb had a big, sharp spike that scientists think was used for defense against predators.1

Iguanodon had a flexible little finger that could grasp objects, unlike its other fingers which were more like hooves.1

When Iguanodon closed its mouth, the bones in its upper jaw would bow out, making the teeth grind against each other like a chewing motion.1

The front of Iguanodon's mouth had no teeth, just a bony beak covered with a hard material for cropping plants.1

Iguanodon could reach food from ground level up to 4 to 5 metres (13 to 16 feet) high, so it ate both low plants and tree leaves.1

In 1878, many complete Iguanodon skeletons were found in a coal mine in Bernissart, Belgium, which helped scientists understand the dinosaur much better.1

Myth buster

Myth: Iguanodon was a slow, clumsy dinosaur that always walked on four legs.

Truth: Iguanodon could walk on two legs or all fours, and it was probably quite agile for its size.2

For dino experts

Scientific name: Iguanodon
Named by: Mantell 18253
Group: Beaked plant-eaters
Family / clade: Ankylopollexia3
Classification: Ornithischia > Ornithopoda > Iguanodontia3
Age of the rocks: 155 to 66 million years (Kimmeridgian to Maastrichtian)3
Rock formations: Arcillas de Morella, Weald Clay, Wessex3
Countries: United Kingdom, Spain, Germany, France, Portugal, Belgium3
Fossil records: 133 in the Paleobiology Database3
Also known as: Heterosaurus, Iguanosaurus, Struthopus, Therosaurus (older names now counted as the same animal)3
Discovery: Iguanodon was first named by Gideon Mantell in 1825 based on fossil teeth found in Sussex, England. Later, in 1878, many complete skeletons were discovered in a Belgian coal mine and studied by Louis Dollo.1
Still debated: Scientists still debate exactly what plants Iguanodon ate. Some think it ate horsetails, cycads, and conifers, while others link it to the spread of flowering plants.1

Where the facts come from

Iguanodon (en.wikipedia.org)
Iguanodon | Diet, Habitat & Extinction (britannica.com)
Iguanodon in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.

Every fact on this page has a number that points to its source. If we got something wrong, sorry, we are dino fans, not a science journal. Tell us at hello@dinowiki.app and we will fix it.