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. 2009 Jan;5(1):e1000267.
doi: 10.1371/journal.ppat.1000267. Epub 2009 Jan 30.

The sicker sex

Marlene Zuk  1
Affiliations

The sicker sex

Marlene Zuk. PLoS Pathog. 2009 Jan.
No abstract available

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Sex differences in Immunity as a Function of Sexual Selection.
The thick solid line represents the case when the condition-dependence of reproduction and the effect of immunity on condition are equal for the sexes; under these circumstances, when sexual selection is absent or weak, males should invest more in immune defense than should females (i.e., thick, solid black line is above the dashed line, in the region of M>F investment in immunity). As the strength of sexual selection increases, the female bias in investment in immunity increases. However, if parasites have particularly strong negative effects on condition in males, and/or if male reproductive success is highly dependent on condition, relative to those same effects in females, males should invest more in immunity than should females, even when sexual selection is strong (thin solid line raised above the thick solid line, and never crossing dashed line). Of course, the converse situation may mean that males never invest more in immunity than do females (lower thin solid line). Adapted from Stoehr and Kokko .
See this image and copyright information in PMC

References

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    1. Zuk M, McKean KA. Sex differences in parasite infections: patterns and processes. Int J Parasitol. 1996;26:1009–1024. - PubMed
    1. Klein SL. Hormones and mating system affect sex and species differences in immune function among vertebrates. Behav Proc. 2000;51:149–166. - PubMed
    1. Zuk M. New York: Harcourt, Inc; 2007. Riddled with life: friendly worms, ladybug sex, and the parasites that make us who we are.
    1. Trivers RL. Parental investment and sexual selection. In: Campbell B, editor. Sexual selection and the descent of man, 1871–1971. London: Heinemann; 1972. pp. 136–179.

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