Giraffes may have developed such long necks over the time of their evolution as a distinct animal species. It may have been a result of adapting to an environment ( they live in savannas, woods, and forests in Africa ), and increased their chances of living longer. It may have helped them in everdag survival for example, if they lived in areas with very tall trees their long necks would have made it easier to kill prey for food or even to fight their competition.