"Perception of fairness may have played a role in the evolution of cooperation"

Cats too. If you go somewhere and you're not back in a reasonable amount of time, they won't talk to you. They might even set with their backs to you.

if I am late home, my dog greets me, sniffs my bag, and if she smells nothing for her, will walk away with her nose in the air and not talk to you for an hour! so I have learnt my lesson well!! if i am late, i ALWAYS bring her something to appease!!

What a great clip Einbar! But I have grown to expect as much from you

When a cat sits with its back turned, it's a sign of feline depression.