Genetic diversity and Capillaria hepatica (Nematoda) prevalence in Michigan deer mouse populations

There have been few field tests of the hypothesis that homozygous populatio ns are prone to high levels of disease. I tested for a negative correlation between genetic diversity and parasitism by estimating the allozyme hetero zygosity, population density, and proportion of individuals infected by Cap illaria hepatica (Nematoda) in nine Michigan populations of deer mice (Pero myscus maniculatus). Parasite prevalence was correlated negatively with het erozygosity when the effects of density were held constant, but was not cor related with population density after controlling for the effects of geneti c diversity. These data support the prediction that inbred populations will be more susceptible to parasite infestations.