Chimpanzees observed making fashion choices [View all]
By Ben Guarino
Its a trend thats taken a troop of chimpanzees by storm: a blade of grass dangling from an ear. The "grass-in-ear behavior," as scientists have termed it, seems to be one of the first times that chimpanzees have created a tradition with no discernible purpose -- a primate fashion statement, in other words.

Theres no doubt that chimpanzees have culture, as different chimp groups will use unique tools: to groom, to crack open nuts, to fish for termites.
But, according to a study in the journal Animal Cognition, chimpanzee culture now includes something that seems altogether arbitrary: ear accoutrements.
Our observation is quite unique in the sense that nothing seems to be communicated by it, says study author Edwin van Leeuwen, a primate expert at the Max Planck Institute in The Netherlands.
To figure out if this was really a tradition, and not just chimpanzees sticking grass in their ears at random, van Leeuwen and his colleagues spent a year observing four chimp groups in Chimfunshi Wildlife Orphanage Trust, a sanctuary in Zambia. Only one troop performed the grass-in-ear behavior, although all of the chimps lived in the same grassy territory. Theres no genetic or ecological factors, the scientists believe, that would account for this behavior -- only culture.
more
https://www.thedodo.com/for-the-first-time-chimpanzees-605888880.html