Data from: Genetic erosion in wild populations makes resistance to a pathogen more costly

Populations that have suffered from genetic erosion are expected to
exhibit reduced average trait values or decreased variation in adaptive
traits when experiencing periodic or emergent stressors such as infectious
disease. Genetic erosion may consequentially modify the ability of a
potential host population to cope with infectious disease emergence. We
experimentally investigate this relationship between genetic variability
and host response to exposure to an infectious agent both in terms of
susceptibility to infection and indirect parasite-mediated responses that
also impact fitness. We hypothesized that the deleterious consequences of
exposure to the pathogen (Batrachochytrium dendrobatidis) would be more
severe for tadpoles descended from European tree frog (Hyla arborea)
populations lacking genetic variability. Although all exposed tadpoles
lacked detectable infection, we detected this relationship for some
indirect host responses, predominantly in genetically depleted animals, as
well as an interaction between genetic variability and pathogen dose on
lifespan during the post-metamorphic period. Lack of infection and a
decreased mass and post-metamorphic lifespan in low genetic diversity
tadpoles lead us to conclude that genetic erosion, while not affecting the
ability to mount effective resistance strategies, also erodes the capacity
to invest in resistance, increased tadpole growth rate and metamorphosis
relatively simultaneously.