Ondi Crino, Kristoffer H Wild, Christopher R. Friesen, Dalton C Leibold, Naomi Laven, Amelia Y. Peardon, Pablo Recio, karine Salin, Daniel W.A. Noble

As global temperatures continue to rise due to climate change, developing animals may be increasingly exposed to elevated temperatures. Developing vertebrates can be affected by elevated temperatures directly, and indirectly through maternal effects such as increased exposure to prenatal glucocorticoid hormones. Although many studies have examined how elevated temperatures and glucocorticoid exposure during development independently affect vertebrates, fewer studies have tested the combined effects of elevated temperature and glucocorticoids. We tested interactions between incubation temperature and prenatal corticosterone exposure in the delicate skink (Lampropholis delicata). We dosed eggs with high or low dose corticosterone treatments early in development and incubated eggs at either 23°C (cool) or 28°C (warm). We measured the effects of these prenatal treatments on development time, body size, survival from hatching to adulthood and on adult hormone levels (corticosterone, thyroxine, and testosterone in males) and mitochondrial respiration in liver tissue. We found no evidence for interactive effects of incubation temperature and prenatal corticosterone exposure on phenotype. However, incubation temperature and corticosterone treatment each independently decreased body size at hatching and these effects were sustained into the juvenile period and adulthood. We found that lizards exposed to low doses of corticosterone during development had elevated levels of baseline corticosterone as adults. Additionally, we found that lizards incubated at cooler temperatures had higher levels of baseline corticosterone. We found that lizards incubated at cooler temperatures had more efficient mitochondria compared to lizards incubated at warmer temperatures. Our results show that developmental conditions can have sustained effects on morphological and physiological traits in oviparous lizards but suggest that incubation temperature and prenatal corticosterone do not have interactive effects.