• Question: Why do dogs wag their tails when they're happy. And why do they curl their tails under if they're depressed?

    Asked by cookieland to Sam on 22 Jun 2011.
    • Photo: Sam Tazzyman

      Sam Tazzyman answered on 22 Jun 2011:

      Good question – I don’t know exactly. Dogs evolved from wolves (actually they still are wolves, just strange looking ones) and wolves live in packs. Animals that live in groups need some form of social signalling to organise them, especially in cases like wolves which are hunting animals and so need to be well organised to catch their prey. So I guess they evolved signals like tail wagging and putting tail between legs to sort out which wolves are the leader and which aren’t.