According to evolutionary theory, an animal goes through physical changes according to genetic mutations that occur, which in turn are influenced (is the influence direct or indirect?) by environmental changes. When a genetic mutations occur in humans for example, the result is a handicapped human right? I am assuming this is the same for other animals as well. So if this is true, then wouldn't the genetic mutations that occur in an animal (as a result of environmental changes) cause a handicap to occur in the animal's body?