Abstract

The effect of temperature on embryonic development and offspring phenotype has received increasing attention. Most of these studies are based on constant-temperature incubations, however, rather than on fluctuating temperatures that mimic nest temperatures. In this study, we conducted a common garden incubation experiment on Asian Yellow Pond Turtles (Mauremys mutica), with a 2 (populations) × 2 (nest temperatures) factorial design, to identify the phenotypic consequence of embryonic responses to latitudinal variation in developmental temperatures. The embryos of the low-latitude population developed faster than those of the high-latitude population; hatching success and hatchling mass did not differ between populations or temperatures. The carapace length and width were not affected by incubation temperature but were greater in hatchlings from the low-latitude population than from the high-latitude population. The offspring from the high-latitude population had better righting ability (despite smaller body size) than those from the low-latitude population. Our results did not show a significant interaction between population origin and nest temperature on embryonic development, which contradicts the conclusion from the constant-temperature incubation experiments for this species. This highlights the importance of fluctuating-temperature effects (mimicking field nests) on the embryonic development in understanding the developmental plasticity of reptiles.