In 1859 Charles Darwin published one of the most influential, and controversial, books ever written: The Origin of the Species. Twelve years later, his follow up, The Descent of Man, and Selection in Relation to Sex, in which he applied his theory of evolution to human reproduction, would prove to be equally shocking and transformative. We’ll take a look at a first edition copy of The Descent of Man, explore some of the questionable ideas it would launch, and trace the evolution of these naturalist classics as they were published in hundreds of different editions from the 1800s to the present day.