This criterion is essential. It points out how human norms and conventions vary in the ritualised behaviours present in nonhuman primates. Several authors have described possible iconographical influences from Mesopotamia into the Indus Valley.[ninety eight] Gregory Possehl notes "Mesopotamian themes in Indus iconography", specifically designs related to the Gilgamesh epic, https://medium.com/@spoilmevintagediy/the-rich-history-of-beadwork-a-journey-through-the-ages-4e4fd2e474cf