Early-life environmental conditions influence parasitism at adulthood and life-history of a cuckoo host

Environmental conditions experienced by individuals early in life can
extend into adult phenotypes with potential fitness consequences. Early
life environmental effects can be relevant for hosts because bad early
life conditions may impair host cognition increasing the risk of future
parasitism or lowering parasite recognition. Here we provide a first test
of this possibility by using data from a 16-year study of individually
marked female magpie Pica pica hosts for which we know natal and adult
environments, occurrence of costly great spotted cuckoo Clamator
glandarius parasitism, egg discrimination ability and life history in
detail. Females born in warmer years were more likely to be parasitized in
adulthood and produced fewer offspring throughout their life. Egg
discrimination behavior and lifespan of magpies were not influenced by the
quality of natal environments. These results provide support for the idea
that there exists annual environmental variation potentially promoting
cohort effects in magpie hosts that may have an impact on cuckoo-host
co-evolutionary dynamics.