Sex-specific transgenerational effects of diet on offspring life history and physiology

Dietary variation in males and females can shape the expression of offspring life histories and physiology. However, the relative contributions of maternal and paternal dietary variation to phenotypic expression of latter generations is currently unknown. We provided male and female Drosophila melanogaster diets differing in sucrose concentration prior to reproduction, and similarly subjected grandoffspring to the same treatments. We then investigated the phenotypic consequences of this dietary variation among grandsons and granddaughters. We demonstrate transgenerational effects of dietary sucrose, mediated through the grandmaternal lineage, which mimic the direct effects of sucrose on lifespan, with opposing patterns across sexes; low sucrose increased female, but decreased male, lifespan. Dietary mismatching of grandoffspring-grandparent diets increased lifespan and reproductive success, and moderated triglyceride levels, of grandoffspring, providing insights into the physiological underpinnings of the complex transgenerational effects on life histories.