Here’s proof to my long-cherished theory that skin color is literally just caused by being closer to or farther from the Equator and the resulting sun exposure and skin darkening. And this is the thing some people hate other people over…
The conlusion of the study by George Chalpin referenced on the above map is that skin coloration in indigenous peoples is strongly related to levels of ultraviolet radiation (UVR). The researchers investigated the relationships of skin reflectance to seasonal UVR levels and other environmental variables, 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 the 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.
This map indeed proves that what people have termed as “race” is only about the amount of sunshine we get as humans, nothing more.