Adaptive Phenotypic Plasticity in an Aquatic Community

无尾无尾轮虫(Rana Pirica)、无尾无尾轮虫(Rana Pirica)和火蜥蜴幼虫是春季在北海道周边森林中形成的池塘群落的创建者。火蜥蜴幼虫在一定的条件下，在幼体发育期内成为宽头变种。具有宽头的幼体火蜥蜴是一种强大的捕食者，有能力吞下同种幼虫和大开口的蝌蚪。宽头畸形被认为是一种适应性表型可塑性。蝌蚪也表现出表型可塑性。当蝌蚪暴露在幼体火蜥蜴的捕食风险中时，它们会形成一个凸起的身体。这种隆起的体型防止被张开大嘴的火蜥蜴吞咽。火蜥蜴幼体的可塑性是捕食者-被捕食者相互作用的对抗性协同进化，蝌蚪对群落中其他捕食者物种表现出另一种诱导防御形态。蜻蜓幼虫是池塘群落中最常见的捕食者物种之一。当蝌蚪暴露在蜻蜓幼虫的捕食风险中时，它们会发展出更高的尾巴形态。中国对虾蝌蚪有两种诱导防御形态。一种是专业型诱导形态对幼体火蜥蜴捕食风险的诱导，另一种是通用型形态对池塘群落中其他各种捕食性物种的诱导。

Anuran tadoles of Rana pirica, and salamander larvae of Hynobius retardatus are the founders of the ponds community that are formed in forests peripheral in Hokkaido in spring. The salamander larvae become a broad headed morph in the larval developmental period in certain condition. Larval salamanders having a broad headed-morph are a strong predator that has an ability to swallow conspecific larvae and tadpoles with a large gape size. The broad-headed morph is considered as an adaptive phenotypic plasticity. The tadpoles also exhibit a phenotypic plasticity. The tadpoles develop a bulgy body when they are exposed to the predation risk of the larval salamanders. The bulginess prohibits being swallowed by the salamanders having a large gape. The plasticity of larval salamander, bread-head, and of tadpole, bulgy body, are considered as antagonistic coevolution of predator-prey interaction.The tadpoles exhibit the other type of inducible defense morphology to the other predator species in the community. Dragon fly larvae are one of the commonest predator species in the pond community. The tadpoles develop higher tail morphology when they are exposed to the predation risk of the dragon fly larvae. Tadpoles of R. pirica have two types of inducible defense morphologies. One is the specialist type inducible morphology to the predation risk of the larval salamander, and the other on is the generalist type one to the various other predator species in the pond community.