Prehistory
Depictions of human sexual activity with animals appear infrequently in prehistoric art. Possibly the oldest depiction, and the only known example from the Palaeolithic (prior to the domestication of animals), is found in the Vale do Côa in Portugal. It shows a man with an exaggerated, erect penis juxtaposed with a goat. However, there is some doubt that the two figures are contemporary; while the goat is depicted in characteristic palaeolithic style, the scene may have been altered in a later period with the insertion of the human figure.
From the Neolithic onwards, images of zoophilia are slightly more common. Examples are found at Coren del Valento, a cave in Val Camonica, Italy, containing rock art dating from 10,000 BCE to as late as the Middle Ages, one depicting a man penetrating a horse, and Sagaholm, a Bronze Age cairn in Sweden where several petroglyphs have been found with similar scenes.
Read more about this topic: History Of Zoophilia