Why animals have tail?
Animals have tails for assisting in balance and steering, propulsion, grasping, grooming (swatting flies is one example) and for display. One of the gaudiest tail displays I can think of is the male peacock’s tail. Believe it or not, we still have remnants of tails because or ancestors did. This is a good example of a useful characteristic (the tail) evolving in our ancestors but not being retained in the descendants (us!) because of a loss of evolutionary selective pressure. Because we can modify our environment, it is unlikely that we will evolve to regain tails!
