They hold court over their juvelines and enforce behaviour, and they mourn the passing of members of the community.
I think it's possible the niche encourages large brains. A bit of nature not nurture maybe.
They are tool users. And they can teach offspring lessons learned from humans, and recognize friend and foe. Well mostly: cyclists are routinely mis-cast as foe no matter what. This is why Australian cyclists look like demented wheelie porcupines: cable ties on the helmet keep the eye-peckers at bay.