 The most specific evidence on the role of social rank in producing stress-induced damage comes from studies of non-human primates (Brunner &amp; Marmot 2006; R. Evans, Hodge, &amp; Pless 1994). In various primate species, social life is organized in terms of clear and stable dominance hierarchies. Robert Sapolsky and Glen Mott (1987) found that hierarchies of free-ranging male baboons exhibit an inverse social gradient both in cortisol elevations and in adverse cholesterol ratios. Manipulating the dominance hierarchy of captive female macaque monkeys, Carol Shively and Thomas Clarkson (1994) similarly found that dominant monkeys who became subordinate had a five-fold excess of coronary plaques as compared to those who remained dominant. (Part of this excess was due to the stress associated simply with a change in social rank [as distinct from a demotion], since subordinate monkeys who became dominant also had more atherosclerosis [albeit, only twice as much] compared to those who remained subordinate).