HISTOLOGICAL ASPECTS OF SKIN PIGMENTATION IN INDIGENES OF THE TERRITORY OF PAPUA‐NEW GUINEA

Abstract

THIS project has been undertaken for two main reasons. Firstly, the racial origin of the New Guinea indigenes and their migration paths through New Guinea are still uncertain, despite the collection of a large amount of data, especially on blood groups (Macintosh et al., 1958 ; Walsh et al., i960 ; Rieckmann et al., 1961). The recent blood group investigations on the Pacific peoples have been reviewed by Simmons (1961). Further work is clearly needed, which must be correlated with the physical and social anthropology (Macintosh et al., 1958). Skin colour represents one aspect of this complex. Secondly, despite the considerable amount of investigation of skin colour performed in recent years, particularly by spectrophotometry, as Blum (1961) points out, little optical or histological study has been carried out on skins intermediate between Negro and White. Skin colour is thought to be a resultant of many factors. Three groups of pigments are present in human skin, carotinoids, haemoglobin (both oxyand reduced) and melanin. The colour imparted by the pigments is modified by the physical properties of the stratum corneum, such as thickness, turbidity and light-scattering action. (a) Carotinoids. Carotinoids, responsible for the yellow colour of the subcutaneous tissue, are also present in the dermis and occasionally, in small quantities, in the epidermis (Edwards and Duntley, 1939). They are probably of minor importance in skin colour.