Water maintenance of a terrestrial frog (Chirixalus idiootocus) egg

• Main Authors: Hsiao-Hui Tsai, 蔡筱蕙
• Other Authors: Kuang-Yang Lue
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/83246772610687159748

碩士 === 國立臺灣師範大學 === 生物學系在職進修碩士學位班 === 92 === The endemic tree frogs Chirixalus idiootocus lay their eggs in rather moist environment on land. In the laboratory, we study the structure of the egg, the rate of dehydration and rehydration of the egg, the embryo tolerance of desiccation, the function of the egg capsule in water balance, and the influence of various sizes of egg mass and substrate moisture. The egg loses water freely by evaporation in various humidity conditions, the lost of water comes from the capsule and not from the embryo. The egg lost 80% hydrated weight water could recovery very quick to initial diameter after flooded within 15 minutes. The weight of hydrated eggs can be reduced by 80% to 90% without affecting embryo viability. Egg mass can reduce water loss and substrate moisture can be taken up water by eggs to resistant desiccation. The rate of development, structure of egg capsule, choice of oviposition site and form of egg mass are other important factors relevant to the terrestrial survival of embryo.