Meeting Abstract
The environment experienced by mothers during gestation can have profound impacts on the phenotype and subsequent survival of their offspring via transgenerational maternal effects. Transgenerational effects of maternal exposure to environmental stressors are most often assumed to be negative. However, maternal stress effects could benefit offspring if it better adapts them to life in a stressful environment. In this study we experimentally explore the role of glucocorticoid hormones (produced in response to stressors) as a link between maternal stress and maternal and offspring life history. We subjected gravid eastern fence lizards (Sceloporus undulatus) to a chronic low-level stress treatment (topical application of a low-concentration dose of corticosterone) until laying. This treatment was designed to emulate the physiological effects of a single daily fire-ant attack, an ecologically relevant low-level environmental stressor. Hatchlings produced by these females were then raised in enclosures either with fire ants present or excluded to provide a test of whether maternal stress resulted in offspring better-adapted to stressful environments. Gravid females treated with a low dose of glucocorticoid hormone suffered a greater loss of body condition and experienced higher gestational mortality than control females. The eggs laid by physiologically stressed females were also less likely to hatch. Hatchling survival, however, was not influenced by maternal stress treatment, irrespective of their environment. This study provides evidence that maternal stress, mediated by glucocorticoids, can have important fitness costs imposed before offspring hatch.
