Why Do Dogs Wag Their Tails?

Dogs wag their tails when they are happy. Just like us when we're happy, we can't sit still, can we? We jump up and down, and clap hands to show how happy we are. In the same manner, a dog shows it with its tail when it is feeling happy or angry. For many animals the tail is the most expressive part of the body. While dogs wag their tails when they are happy, a cat expresses itself differently. When it is feeling conceited or proud, its tail will stick straight up into the air. Certain monkeys will put their tails up and swish them to and fro to frighten off a potential enemy. Horses hold their tails high when they are feeling full of spirit and want to race around.