Lamarck’s theory of evolution, has been now revived by a number of prominent biologists. Changes in animal occur through use and disuse. Organs which are specially exercised specially developed. The need for this special exercise changes the animal. The giraffe, for instance has developed its long neck higher and higher branches of tree. Organs that are never exercised disappear altogether. The eyes of animals that have taken to live in dark until the late descendants are born eyeless. The great assumption made by this story offspring of that individual. This is a doctrine dispute among modern biologists.