 Other rich areas are the palm, forearm and inside the elbow, with from 18 to 32 species.The head and the trunk hosted between 2 and 10 each.The umbilicus, or navel, is an area of the body that is rarely exposed to UV light, soaps, or bodily secretions (the navel does not produce any secretions or oils) and because it is an almost undisturbed community of bacteria it is an excellent part of the skin microbiome to study.