About Gideon Mantell
Trained as an obstetrician, Gideon Mantell was inspired to hunt for fossils by the example of Mary Anning (who unearthed the remains of an ichthyosaur in 1811, on the English coast). In 1822, Mantell (or his wife; the details are murky on this point) discovered strange, giant teeth in the county of Sussex. Intrigued, Mantell showed the teeth to various authorities, one of whom, Georges Cuvier, initially dismissed them as belonging to a rhinoceros. Shortly thereafter, it was established beyond any dispute that the teeth were left by an ancient reptile, which Gideon named Iguanodon--the first example in history of a dinosaur fossil being discovered, analyzed, and assigned a specific genus.
Although he's best known for Iguanodon (which he initially wanted to name "Iguanasaurus"), Mantell specialized in England's late Cretaceous fossil deposits, which yielded the remains of numerous (non-dinosaur) animals and plants. In fact, one of his limited-edition books, The Geology of Sussex, received a terse bit of fan mail from none other thank King George IV: "His majesty is pleased to command that his name should be placed at the head of the subscription list for four copies."
Sadly for Mantell, after his discovery of Iguanodon, the rest of his life was anticlimactic: in 1838, he was forced by poverty to sell his fossil collection to the British Museum, and after a long illness he committed suicide in 1852. Weirdly, one of Mantell's paleontological rivals, Richard Owen, got hold of Mantell's pickled spine after his death and displayed it in his museum! (Owen--the coiner of the word "dinosaur" who never gave Mantell the credit he deserved--is also believed to have written an anonymous, damning obituary of Mantell after the latter's death, which didn't prevent a future paleontologist from naming a genus in his honor, Mantellisaurus.)