Transgenerational effects of parental nutritional status on offspring development time, survival, fecundity, and sensitivity to zinc in Chironomus tepperi midges.

Environmental stimuli can induce plastic changes in life history traits, and stimuli experienced by parents can be transmitted to the next generation ("transgenerational") through the inheritance of factors unrelated to changes in DNA sequences. Transgenerational effects are common in species living in habitats subjected to recurrent stressful events, such as fluctuating resource availability. In a previous study, the nutritional status of the midge Chironomus tepperi has been reported to influence life history traits of the offspring. In this study we investigated whether they also alter sensitivity of offspring to zinc. Offspring of parents reared under low food conditions had a shorter development time and lower reproductive output compared to offspring of parents raised under excess food. While zinc exposure decreased the survival of offspring generally, the interaction between parental food level and zinc exposure did not influence the relative sensitivity of offspring toward zinc. Parental nutritional stress therefore triggered transgenerational effects, potentially acting as confounding factors in ecotoxicological studies, but they did not directly affect the susceptibility of offspring to zinc.