Evolution didn't leave humans with tails, but science is attempting to change that. Japanese researchers say some people, especially the elderly, could benefit from an extra appendage. The device attaches to the waist and moves in eight directions with artificial muscles and compressed air. While it's meant to mimic the tail of a monkey or a cheetah, it's not very practical for people at the moment. InsideEdition.com's Mara Montalbano has more.