The Comte de Gobineau was a notorious racist, but he got some things right. Mythical monsters, he suggested, emerge not from overactive imaginations but from impoverished thinking. Cultures label outsiders as demonic or bestial or imperfectly human because unimaginative people cannot conceive of strangers in the same terms as themselves. When European explorers and imperialists encountered unfamiliar cultures, therefore, they usually havered over where to place them in the classical and biblical panorama of creation. Henry the Navigator identified black Africans as woodhouses – the ‘wild men of the woods’ of medieval legend. Early woodcut images of cannibals in Java showed them as cynocephali – the dog-headed men reported in Pliny’s Natural History. Patagonia got its name from the reputed giants whom Antonio Pigafetta claimed to see when he sailed there with Magellan. Francisco de Orellana named the Amazon after the monstrous women that supposedly inhabited the river’s shores. Minds that expected marvels slotted new discoveries into the nether links of the Great Chain of Being, between humans and beasts.

Yet travelogues had a reputation for unreliable sensationalism, so doubts as to the very existence of monsters survived. More than 1,000 years before ocean-going voyages disclosed worlds of wonder in the Atlantic, St Augustine suggested that freaks of nature were illusory – evidence of men’s inability to see the beauty