Hieronymus Bosch (Jeroen van Aken, ca 1450-1516), The Garden of Earthly Delights, triptych (ca 1500), central panel detail 1.
Prado Museum, Madrid.

In the middle ground of the central panel, men are riding horses, unicorns and other four-legged animals and revolve in a wide circle around a pool with seductive bathing maidens, the two sexes being as yet carefully segregated. In the centre behind the pool, an enormous blue globe rises out of a lake, with at either side huge rosy-blue pavilions of pleasure. Inside an opening on the globe just above the water level, a man touches a woman’s private parts with her consent, while nearby a loving pair is swimming in front of them. At the turn of the fifteenth century, animals often served to symbolize the lower appetites of humankind and the act of riding beasts was commonly employed as a metaphor for the sexual act, which was seen in the Middle Ages, at best a necessary evil, at worst a deadly sin, the deadly sin of Lust.