Phorusrhacos Pithecanthropus (now considered the same as Homo erectus) Toxodon Other creatures on the Plateau Ixodes maloni, a species of blood-sucking tick; named after Malone, the first to be bitten by one Moths; some large specimens were seen flying around the expedition's campfire. A 50-foot-long black snake was seen by the expedition. Creatures outside the Plateau Jararaca Agouti Tapir Jaguar References in other works The idea of prehistoric animals surviving into the present day was not new, but had already been popularized by Jules Verne in Journey to the Center of the Earth. In Jules Verne's book, published in 1864, the creatures live under the earth in and around a subterranean sea. In 1915, the Russian scientist Vladimir Obruchev produced his own version of the "lost world" theme in the novel Plutonia, which places the prehistoric species in a fictional space inside the hollow Earth connected to the surface via an opening in the Russian far north. In 1916, Edgar Rice Burroughs published The Land That Time Forgot. His "lost world" was discovered by German submariners in Antarctica. In addition to lending its title to this subgenre, the title of Doyle's work was reused by Michael Crichton in his 1995 novel The Lost World, a sequel to Jurassic Park, and its film adaptation, The Lost World: Jurassic Park. Two of the characters in Crichton's novel mention a palaeontologist called John Roxton. References to actual history, geography and current science The characters of Ed Malone and Lord John Roxton were modelled, respectively, on the journalist E. D. Morel and the diplomat Roger Casement, leaders of the Congo Free State reform campaign (the Congo Reform Association), which Doyle supported. In 1911, just when Doyle was writing the book, Casement made a second such anti-slavery reform campaign in the Amazonian part of Peru. Doyle was aware of his good friend Percy Harrison Fawcett's expedition to the Huanchaca Plateau in Noel Kempff Mercado National Park, Bolivia. Fawcett organised several expeditions to delimit the border between Bolivia and Brazil – an area of potential conflict between both countries. Doyle attended Fawcett's lecture to the Royal Geographical Society on 13 February 1911 and was impressed by the tale about the remote "province of Caupolican" (present day Huanchaca Plateau) in Bolivia – a dangerous area with impenetrable forests, where Fawcett saw "monstrous tracks of unknown origin". Fawcett wrote in his posthumously published memoirs: "Monsters from the dawn