Q. Iguanodon teeth

The first Iguanodon (Iguanodon anglicus) teeth ever found, sparking the discovery of dinosaurs, 141 to 137 million years old.

Left by giants

Mary Ann Mantell (1795-1869).

Mary Ann Mantell (1795-1869).

The teeth were found by Mary Mantell in 1822 as she pulled at loose fragments of a rock by the side of the road in Sussex.

Her amateur palaeontologist husband Gideon noticed they were similar to modern iguana teeth, but 10 times larger.

He had the imagination to suggest they belonged to a colossal ancient herbivorous lizard he named Iguanodon. Gideon Mantell had no idea how huge his idea was.

Hidden monsters

Image of Megalosaurus jaw and teeth

Megalosaurus jaw and teeth from William Buckland’s Notice on the Megalosaurus or Great Fossil Lizard of Stonesfield, 1824.

Huge carnivorous reptile fossils had lurked in the bowels of Oxford University’s Museum since 1676. The first keeper thought they belonged to a giant man, but in 1815 the academics began to realise the bones were reptilian.

After unearthing more and consulting other anatomists they confirmed their theory, eventually naming the reptile Megalosaurus.

Dinosaurs launch

Gideon Mantell (1790–1852).

Gideon Mantell (1790–1852).

Until the Mantells uncovered these teeth, no equivalent giant herbivorous reptiles had been found. The idea seemed implausible and at first Gideon struggled to be heard by the scientific establishment. What did a provincial doctor and cobbler’s son know?

To his despair, experts dismissed the teeth as mammalian, possibly from a rhinoceros, and much younger than Mantell judged from the type of rock.

Terrible lizards



But Mantell didn’t give up. He found more teeth together with bones and eventually convinced the experts he was right.

Over the next 20 years more giant lizard fossils were found. Then in 1842 anatomist Richard Owen, this Museum’s first superintendent, did something ingenious. He announced a new name for grouping together land-dwellng reptile fossils: the dinosauria, terrible lizards. It grabbed the headlines and seeded a legend.

Savage rivalry

The Country of the Iguanodon from The Wonders of Geology, 1838, Volume 1, by Gideon Mantell.

The Country of the Iguanodon from The Wonders of Geology, 1838, Volume 1, by Gideon Mantell.

Ruthlessly ambitious, Owen accepted the glory for the discovery of dinosaurs when it should have been Mantell’s. Owen is still remembered as ‘the man who invented dinosaurs’.

To Mantell, whose class had forced him to fight for recognition, Owen’s behaviour was ‘unworthy piracy… what a pity a man of so much talent should be so dastardly and envious’.

Around the Museum

The Dinosaurs gallery.

Meet a terrifying T. rex, unearth some Baryonyx bones and inspect the Triceratops skeleton in the Dinosaurs gallery, in the Blue Zone.