There are more than 200 genera and around 6,500 known species of long-legged fly. They can be found just about everywhere on Earth, including the Tropics and at high altitudes. The 45-million-year-old long-legged fly pictured is identical to specimens alive today. These life forms, which have remained unaltered for millions of years, completely overturn the claim that living things descended from one another by undergoing small changes over lengthy periods of time.