The Naked Ape: A Zoologist's Study of the Human Animal is a 1967 book by zoologist and ethologist Desmond Morris that looks at humans as a species and compares them to other animals. The Human Zoo, a follow-up book by Morris that examined the behaviour of people in cities, was published in 1969.SummaryThe Naked Ape, which was serialized in the Daily Mirror newspaper and has been translated into 23 languages, depicts human behavior as largely evolved to meet the challenges of prehistoric life as a hunter-gatherer (see nature versus nurture). The book was so named because out of 193 species of monkeys and apes only humans (Homo sapiens sapiens) are not covered in hair. Desmond Morris, the author, who formerly was the Curator of mammals at London Zoo, said his book was intended to popularise and demystify science.Morris said that Homo sapiens not only have the largest brains of all higher primates, but that sexual selection in human evolution has caused humans to have the highest ratio of penis size to body mass. Morris conjectured that human ear-lobes developed as an additional erogenous zone to facilitate the extended sexuality necessary in the evolution of human monogamous pair bonding. Morris further stated that the more rounded shape of human female breasts means they are mainly a sexual signalling device rather than simply for providing milk for infants. Although the book's subject was the many behavioural consequences of the evolutionary transformation from forest-dwelling, mainly vegetarian creatures to carnivorous hunter-gatherers, reviewers predictably focused on the sexual aspects.