Posted by The Conversation | Wednesday 20 January 2021, 12:44 PM (AEDT) The Conversation is asking kids to send in questions they'd like an expert to answer. Goldie, aged 5, wants to know how we can tell when animals who don’t have tails are happy. An expert explains. Animals use their tails for steering, holding, balancing and swimming, but they also use them as a way to talk to each other. A dog wagging its tail is one example, and we usually read a waggy tail as a sign that a dog is happy. But that’s not the only way dogs can show they’re happy, and there are lots of animals that don’t have tails or don’t use them to talk to each other.