Latitudinal differences in temperature effects on the embryonic development and hatchling phenotypes of the Asian yellow pond turtle,Mauremys mutica

Abstract

The effect of incubation temperature on embryonic development and offspring traits has been widely reported for many species. However, knowledge remains limited about how such effects vary across populations. Here, we investigated whether incubation temperature (26, 28, and 30 °C) differentially affects the embryonic development of Asian yellow pond turtle (Mauremys mutica) eggs originating from low-latitude (Guangzhou, 23°06′N) and high-latitude (Haining, 30°19′N) populations in China. At 26 °C, the duration of incubation was shorter in the high-latitude population than in the low-latitude population. However, this pattern was reversed at 30 °C. As the incubation temperature increased, hatching success increased in the low-latitude population but slightly decreased in the high-latitude population. Hatchlings incubated at 30 °C were larger and righted themselves more rapidly than those incubated at 26 °C in the low-latitude population. In contrast, hatchling traits were not influenced by incubation temperature in the high-latitude population. Overall, 30 °C was a suitable developmental temperature for embryos from the low-latitude population, whereas 26 and 28 °C were suitable for those from the high-latitude population. This interpopulation difference in suitable developmental temperatures is consistent with the difference in the thermal environment of the two localities. Therefore, similarly to posthatching individuals, reptile embryos from different populations might have evolved diverse physiological strategies to benefit from the thermal environment in which they develop. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114, 35–43.