Geographic distribution of environmental factors influencing human skin coloration
Version of Record online: 4 MAY 2004
Copyright © 2004 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 125, Issue 3, pages 292–302, November 2004
How to Cite
Chaplin, G. (2004), Geographic distribution of environmental factors influencing human skin coloration. Am. J. Phys. Anthropol., 125: 292–302. doi: 10.1002/ajpa.10263
- Issue online: 27 OCT 2004
- Version of Record online: 4 MAY 2004
- Manuscript Accepted: 3 JAN 2003
- Manuscript Received: 10 APR 2002
Skin coloration in indigenous peoples is strongly related to levels of ultraviolet radiation (UVR). In this study, the relationships of skin reflectance to seasonal UVR levels and other environmental variables were investigated, with the aim of determining which variables contributed most significantly to skin reflectance. The UVR data recorded by satellite were combined with environmental variables and data on human skin reflectance in a geographic information system (GIS). These were then analyzed visually and statistically through exploratory data analysis, correlation analysis, principal components analysis, least-squares regression analysis, and nonlinear techniques. The main finding of this study was that the evolution of skin reflectance could be almost fully modeled as a linear effect of UVR in the autumn alone. This linear model needs only minor modification, by the introduction of terms for the maximum amount of UVR, and for summer precipitation and winter precipitation, to account for almost all the variation in skin reflectance. A further significant finding was that the effect of summer UVR seems to reach a threshold beyond which further adaptation is difficult. Am J Phys Anthropol, 2004. © 2004 Wiley-Liss, Inc.