This criterion is very important. It points out how human norms and conventions differ within the ritualised behaviours present in nonhuman primates. The capacity for symbolic assumed is not the crucial defining element for modern human behaviour. It is very the use of symbolism to organise behaviour that defines us. https://medium.com/@spoilmevintagediy/the-rich-history-of-beadwork-a-journey-through-the-ages-4e4fd2e474cf