The Effets Of Different Environmental Factors On Egg Incubation,Hatchling Phenotypes And Learning Ability In The Three-keeled Pond Turtles,Mauremys Reevesii

The emergence of environmental problems, such as global warming and pesticide residues, is resulting to increasingly severe changes in current ecological environments and make animal survival face the challenge of survival. Most reptile species oviparous, and do not express parental care behaviors. The develppment of reptile embryos in the natural nests is affected by the changes of external environment, and has a profound influence on the phenotypes and functional behaviors of hatchlings. The spatial learning ability of animals is a kind of neural activity for survival and evolution, reflecting ecological effects causing by the interaction between animals and environment and their impacts on themselves, and has important roles for understanding the external environments, locating safe shelters, protecting against potential predators and managing adverse microhabitats. Therefore, it is related to animal survival and fitness.Here, we used Mauremys reevesii as an object of study, and hatched eggs by under different temperature (26,28 and 30℃), pesticide (2,20,200 and 2000ppm) and oxygen concentration (normal and hypoxic) conditions to determine the effects of incubation temperature, pesticide and hypoxia on embryonic development, phenotypes and learning ability of hatching turtles. The main results are as following:1. Hatching success of M reevesiis eggs and hatchling size did not differ among different temperature treatments. Incubation length of M. reevesiis eggs in high-temperature treatment was significantly shorter than that in low-temperature treatment. The proportion of hatchlings that successfully righted themselves and righting time did not differ among temperature treatments. In the learning ability test, there is no significant differences in the proportion of hatchings that successfully foraged, number of mistakes, forging time, moving distance in a cross maze.2. Hatching success of M. reevesiis eggs, incubation period and hatchling size did not differ among different Glyphosate concentration treatments. The proportion of hatchlings that successfully righted themselves and righting time did not differ among different Glyphosate concentration treatments. In the learning ability test, there is no significant differences in the proportion of hatchings that successfully foraged, number of mistakes, forging time, moving distance in a cross maze.3. Hatchling size of M. reevesiis did not differ among normoxic and hypoxic treatment. The proportion of hatchlings that successfully righted themselves and righting time did not differ among normoxic and hypoxic treatments. In the learning ability test, there is no significant differences in the proportion of hatchings that successfully foraged, number of mistakes, forging time, but moving distance in a cross maze is longer than hypoxic treatment in a maze experiment.