Data from: Social status, immune response, and parasitism in males: a meta-analysis

In male vertebrates, two conflicting paradigms—the energetic costs of high
dominance rank and the chronic stress of low rank—have been proposed to
explain patterns of immune function and parasitism. To date, neither
paradigm has provided a complete explanation for status-related
differences in male health. Here, we applied meta-analyses to test for
correlations between male social status, immune responses, and parasitism.
We used an ecomimmunological framework, which proposes that males should
re-allocate investment in different immune components depending on the
costs of dominance or subordination. Spanning 297 analyses, from 77
studies on several vertebrate taxa, we found that most immune responses
were similar between subordinate and dominant males, and neither dominant
nor subordinate males consistently invested in predictable immune
components. However, subordinate males displayed significantly lower
delayed-type hypersensitivity and higher levels of some inflammatory
cytokines than dominant males, while dominant males exhibited relatively
lower immunoglobulin responses than subordinate males. Despite few
differences in immunity, dominant males exhibited consistently higher
parasitism than subordinate males, including protozoan blood parasites,
ectoparasites, and gastrointestinal helminths. We discuss our results in
the context of the costs of dominance and subordination, and advocate
future work that measures both parasitism and immune responses in wild
systems.