Sex-specific parasite prevalence is predicted by sexual size dimorphism
in wild birds
- Jose Valdebenito,
- William Jones,
- Tamás Székely
Abstract
Males and females often differ in ecology and behaviour, and these
differences are expected to lead to sex differences in parasite
susceptibility. However, sex differences in parasite prevalence have not
yet been established across a broad range of taxa, and the ecological
and evolutionary drivers of such differences have remained contested.
Here we meta-analyse 942 sex-specific effect sizes in blood and
gastrointestinal parasites of 179 wild bird species, representing 17
avian orders. Females exhibit higher infections in both Haemoproteus and
Protozoan parasites than males and females also have higher prevalence
in both Leucocytozoon and Haemoproteus blood parasites during the
breeding season. Importantly, sex differences in parasite prevalence are
not associated with sexual selection nor parental care, although
male-biased prevalence in Leucocytozoon parasites were predicted by
male-biased size dimorphism. Taken together, breeding systems and sexual
selection have modest influence on sex difference in parasite prevalence
across the avian tree of life.