  We suggest that a particular form of social hierarchy, which we characterize
as 'pathogenic', can, from the earliest stages of life, exert a formal analog
to evolutionary selection pressure, literally writing a permanent developmental
image of itself upon immune function as chronic vascular inflammation and its
consequences. The staged nature of resulting disease emerges 'naturally' as a
rough analog to punctuated equilibrium in evolutionary theory, although
selection pressure is a passive filter rather than an active agent like
structured psychosocial stress. Exposure differs according to the social
constructs of race, class, and ethnicity, accounting in large measure for
observed population-level differences in rates of coronary heart disease across
industrialized societies. American Apartheid, which enmeshes both majority and
minority communities in a social construct of pathogenic hierarchy, appears to
present a severe biological limit to continuing declines in coronary heart
disease for powerful as well as subordinate subgroups: 'Culture', to use the
words of the evolutionary anthropologist Robert Boyd, 'is as much a part of
human biology as the enamel on our teeth'.
