Length
InferredAbout 10 m (museum reference)
A rounded museum reference, not a measured population range; the page does not specify the specimen, method or growth stage. [D1]
EXHIBIT 45
Iguanodon
Iguanodon
A large thumb spike on a plant-eating hand.
TWO WAYS TO PICTURE THE PAST
Science & the silver screen
Compare the evidence with the familiar movie image. The illustrations are not to a shared scale.
01 / SCIENTIFIC RECONSTRUCTION
An animal, reconstructed
Image unavailableIguanodon bernissartensis life reconstruction by Davide Bonadonna; cropped Commons version uploaded by SlvrHwk. Robust beaked ornithopod with chewing cheek teeth and thumb spikes; body held forward rather than in a kangaroo-like upright pose.This scientific picture needs an internet connection. Its source link and image notes remain available.
The artist identifies this reconstruction as Iguanodon bernissartensis. This view illustrates one form within the genus, rather than every species or individual. Fossil-informed anatomy: Robust beaked ornithopod with chewing cheek teeth and thumb spikes; body held forward rather than in a kangaroo-like upright pose. Source crop selects the quadrupedal animal from an original two-pose image. Colours and soft-tissue contours are reconstructed. [1] [2]
Iguanodon bernissartensis (Davide Bonadonna, cropped).png — Davide Bonadonna; cropped Commons version uploaded by SlvrHwk. CC BY 4.0. Remote source artwork displayed without additional cropping; Wikimedia supplies any display-size derivative.
Scientific picture served by Wikimedia · internet connection required.
02 / MOVIE-STYLE INTERPRETATION
A cinematic imagination
Image unavailableOriginal cinematic Iguanodon picture: Cinematic robust Iguanodon with forward-held body, strong hindlimbs, substantial forelimbs, cropping beak and prominent thumb spikes; speculative skin colour, tail balancing the body.The exhibit and its image notes remain available.
Cinematic robust Iguanodon with forward-held body, strong hindlimbs, substantial forelimbs, cropping beak and prominent thumb spikes; speculative skin colour, tail balancing the body. Dramatic lighting, surface detail and scenery are artistic choices. This is an original cinema-inspired picture, rather than a frame from a film or a documented fossil locality.
Original artwork · artistic interpretation.
Scientific view: credited paleoart interpreting fossil evidence, served online by Wikimedia. Movie-style view: Original artistic interpretation. Colors, soft tissues and settings involve reconstruction.
PERIODEarly Cretaceous[1]
DIETHerbivoreInferred from related anatomy [1]
TOTAL LENGTHNot established hereComparable estimate unavailable
FOSSILS FOUNDBelgium, United Kingdom[1]
MEET THE ANIMAL
Meet Iguanodon
Iguanodon bernissartensis was a large plant eater from Early Cretaceous western Europe. An elongated snout ended in a toothless beak, while closely packed teeth farther back in the jaws formed chewing surfaces. Replacement rows supplied new teeth as older ones wore out. This arrangement explains how the animal could process vegetation without identifying every plant it ate. [S1]
Its hand carried an enlarged, spike-like thumb, interpreted as having a horny covering. Defense is one proposed use, rather than a fossilized demonstration of the spike striking an attacker. Movement also involves interpretation: the long tail could counterbalance the front of the body during two-legged activity, while the forelimbs could support walking. The museum account keeps aspects of posture debated. [S1]
The Bernissart coal mine in Belgium yielded around thirty well-preserved skeletons after discoveries in 1878. These connected bones greatly improved understanding of Iguanodon anatomy. One skeleton became the species’ holotype, the name-bearing specimen against which other fossils are compared. The collection made a much clearer animal possible, but its assembly history should not be confused with a directly observed living pose. [S1]
Overview sources
- Iguanodon bernissartensis — PaleontologyRoyal Belgian Institute of Natural Sciences · Accessed 2026-10-04Inspected: page
PREHISTORIC ANIMAL DOSSIER
A life in profile.
The animal, the evidence, and the questions still open.
Iguanodon combined a plant-cropping beak, cheek teeth and a prominent thumb spike. Historical use of the name included several other dinosaurs, so apparent genus-wide distributions require taxonomic review.
Profile scope: Genus: Iguanodon; excludes former species reassigned to Mantellisaurus and other genera.
- Time
- Early Cretaceous
- Fossil locations in this exhibit
- Belgium, United Kingdom
How to read the evidence
Source supported identifies a description documented by the cited source. Inferred marks a reconstruction or functional estimate. Debated marks competing interpretations. Not established means the sources reviewed for this dossier do not support a firm conclusion; it does not mean a behavior never occurred.
A size reference is an estimate, not a population range. Nesting evidence does not by itself establish courtship, mate choice, or lifelong pairing.
Mass
InferredAbout 4,000 kg (museum reference)
A rounded museum reference, not a measured population range; the page does not specify the specimen, method or growth stage. [D1]
Diet and feeding
InferredPlant eater with a beak and cheek teeth
The museum identifies herbivory from the feeding apparatus. Exact plant preferences are not established here. [D1]
Habitat and setting
Source supportedEarly Cretaceous western European fossil localities
The directory records Belgium and England. Older wider distributions include animals reassigned from Iguanodon, so they are not repeated here. [D1] [D2]
Movement
InferredMainly four-legged; bipedal movement also proposed
Museum accounts favor quadrupedal walking while retaining possible two-legged movement. The older upright, tail-dragging posture is not adopted. [D1] [D2]
Distinctive anatomy
Source supportedThumb spike, beak and chewing teeth
The spike is a distinct hand structure. Predator defence is a proposed function, rather than an observed encounter. [D1] [D2]
Reproduction & life together
Reproduction and care
Not establishedNot established here
The reviewed sources do not establish nest structure, incubation or parental care for Iguanodon.
Courtship and mating
Not establishedNot established here
The reviewed sources do not establish a courtship sequence or mating system for Iguanodon.
Social behavior
Not establishedNot established here
The reviewed sources do not establish usual group size or lasting social organization for Iguanodon.
Dossier research & sources
Sources and inspection notes for the claims in this profile.
- Iguanodon — Dino DirectoryNatural History Museum, London · Accessed 2026-10-02Genus profile; rounded educational estimates, usually without specimen, method or maturity. · Inspected: page
- The search for the real IguanodonNatural History Museum, London · Accessed 2026-10-02Historical revision; former I. atherfieldensis is Mantellisaurus atherfieldensis. · Inspected: page
THE STORY IN THE FOSSILS
Meet Iguanodon.
Iguanodon’s hand carried a conspicuous thumb spike, while a beak and cheek teeth suited plant feeding. The Natural History Museum treats predator defence as a likely use for the spike. Its locomotion is reconstructed from bones, with both two-legged and four-legged movement considered in the directory. [1]
The name once covered fossils spanning a wide range of places and geological ages. Re-examination divided some former species into other genera. In particular, Iguanodon atherfieldensis became Mantellisaurus atherfieldensis in 2007; the latter’s shorter forelimbs distinguish it from more heavily built Iguanodon relatives. [2]
A note on scale and time
We have not established a comparable adult total-length estimate for this taxon in this draft. Specimen measurements in the text describe those individuals. The cited dates are approximately 140–110 million years ago. Unknown does not mean zero.
Sources & editorial notes
Sources and evidence notes for this exhibit.
- IguanodonNatural History Museum, London · Accessed 2026-10-02Dino Directory fact panel, thumb-spike and locomotion description, Taxonomic details. Genus profile and generalized 140–110 Ma interval; 10 m/4,000 kg are unscoped educational estimates.
- The search for the real IguanodonNatural History Museum, London · Accessed 2026-10-02Historical broad referrals; Mistaken identity; passage separating Mantellisaurus atherfieldensis in 2007 and comparing forelimbs/posture and thumb spikes. Does not mean former species remain aliases of current Iguanodon.
KEEP EXPLORING
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