Climate, racial category, and body proportions in the U.S.
In 1955, Newman and Munro reported correlations between physical characteristics and climate in a white male U.S. Army sample. For example, the body weight-to-mean annual temperature correlation was -0.460. Because the men descended from relatively recent immigrants to North America, physical clines implicitly derived from differential lifetime growth rather than from natural selection. Consequently, both causation and adaptive function of Bergmann's and Allen's biogeographic rules in humans were called into question. Analysis of male and female data from the 1988 U.S. Army anthropometric survey offers new insights to the 1955 study findings. Using state means of the male subsample identifying themselves as white, as did Newman and Munro, no significant correlations were found between climatic variables and height, weight, BMI, or other body proportions. With individual data rather than state mean values, neither white male nor white female samples showed morphology to climate correlations. Relationships seen in the earlier white sample have disappeared, possibly due to a more uniform growth environment and mobility in the U.S. Black males and females showed some body trait to climate correlations but only at r values of around 0.10. Using state means from the combined sample (racial identification ignored), strong correlations are seen. As examples, mean annual temperature correlates to male relative sitting height at r = -0.634 and to female relative forearm length at r = 0.645. However, these values are evidently spurious, being products of the higher percentages of whites enlisting from colder areas of the U.S.