Whoever told you that is pulling wool over your eyes. Turtles, especially the species that live on land such as box turtles and tortoises, tend to have long lives, often exceeding 100 years, but they are not even the longest living animals. That honor belongs to the arctic clam, which can live 400 years. Semi-aquatic turtles tend to live shorter lives. The painted turtle, for example, lives a maximum of only 61 years. Many individuals in the wild live much shorter lives because of predators, and also because many are road kills. It is not unusual to find people down south deliberately running over turtles with their cars. The reason turtles live long lives is due mainly to their low metabolic rate, since they do not generate internal body heat to stay warm. The low metabolic rate in turn allows their heart to beat slowly and to last longer. Mice, in contrast, generate internal body heat and their hearts beat a fast 500 times a minute. As a result, mice only live 2-3 years maximum.