Charles Darwin is getting his due this year. His theory of evolution is being recognised as the most important idea of modern times. But was he the first person to believe that human beings are apes?
At the time, the most controversial aspect of Darwin's intellectual revolution was the conclusion that we, too, have evolved from earlier species, and that our closest relatives are our fellow great apes. DNA evidence has since confirmed exactly how similar we are to chimpanzees. Centuries before Darwin, however, another genius anticipated his discovery.
Leonardo da Vinci held it to be self-evident that we are closely related to apes. He didn't even present it as a case to be argued. In his notes in the Royal Library at Windsor Castle, he simply observes, on the basis of his studies in comparative anatomy, that human beings and monkeys are close cousins. In a plan for a book on anatomy, he proposes to discuss "Man. The description of man, which includes that of such creatures as are almost of the same species, as Apes, Monkeys and the like, which are many".
He explicitly says "apes, monkeys and the like" are not merely related to humans but indeed "almost of the same species". In other words, Leonardo, writing simply on the basis of his own observations more than 500 years ago, says pretty much the same thing the modern science writer Jared Diamond, on the basis of DNA evidence, argues in his book The Rise and Fall of the Third Chimpanzee. Nor is this a stray observation. Leonardo says it again, in a note on internal anatomy: "Describe the various forms of the intestines of the human species (delle spetie umana), of apes and suchlike. Then, in what way the leonine species differ ... "
We revere Darwin for asking questions in the Victorian age that decentred human beings from their ancient delusion of biological uniqueness. How much courage and genius did it take to ask those same questions, as Da Vinci did, 350 years earlier?