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they were of Southern nativity, which was biologically beneficial because the South was
rural, self-sufficient in food production, and the South also received more solar radiation.
Figure 4, Nineteenth Century Soldier and Prisoner Statures by Insolation
Source: See Tables 4 and 5.
Second, consistent with the insolation-stature hypothesis, insolation was
positively related with soldier and prisoner statures and increased with insolation at a
decreasing rate (Figure 4), and soldier and prisoner’s average stature reached a maximum
in insolation at 3.82 hours of incident solar radiation per day. Nonetheless, there were
differences between how soldier and prisoner statures, and soldier and prisoner stature
variation was sensitive to socioeconomic status. If soldier and prisoner statures are
observed at average US insolation levels, soldiers and prisoners came to comparable