A quantitative and morphological study of the pigmentary system of the chimpanzee with the light and electron microscope.

The epidermal melanocyte system of the chimpaneze was studied by the combined skin-splitting DOPA, and electron microscopic techniques. It is very similar to man. There are DOPA-positive epidermal melanocytes in all body regions regradless of the degree of macroscopic skin pigmentation or hirsutism. Furthermore, as in man, but in contrast to rodents, chimpanzee skin contains a very high level of melanocytes in the epidermis; approximately 3,320+/-350 per square millimeter skin. Chimpanzee melanosomes are long, wide, and fully melanized. In keratinocytes, these organelles are individually dispersed in all body regions, regardless of the degree of skin color, as is true for other mammalian species with large melanosomes.