Skeletal Adaptations
Giraffes, lizards, and many other known species adapted to their environments through genetic changes to their skeletons. This form of natural selection meant that members of the population who didn't develop and present these skeletal changes died out. For example, giraffes developed long necks to reach food sources higher up in trees, so members of the giraffe population who didn't develop a long neck died out. At the same time, certain lizards in one region developed longer leg bones to help it climb up during periods of flood and to escape predators in the ground; shorter legged lizards of the same population died out until only the lizards with the long legs survived.
