Illustration of a “monster” born in Ravenna, Italy, in 1512: the X and Y markings shown on the body an uncannily prophetic nod to how human sex chromosomes are now named.

Featured on PDR in the essay When the Birds and the Bees Were Not Enough: Aristotle’s Masterpiece

Mary Fissell on how a wildly popular sex manual — first published in 17th-century London and reprinted in hundreds of subsequent editions — both taught and titillated through the early modern period and beyond.