Maintenace mechanism and evolution of enantiomorphy in snails

本项目旨在探讨树蜗牛对象的维持机制及其进化分化过程，重点研究对象动态平衡相关性状的功能和分化。最近的研究对象是继续对形态频率进行长期调查，并评估对映异型的相对交配频率。我们还对生殖器官进化的系统发育假说进行了验证。我们在野外发现了对映异型动物之间意外成功的交配，这是负频率依赖选择可能维持对映异型的第一个行为证据。我们的分子系统发育表明，对形性在两栖属中持续存在至少100万代，因此对形性在进化上是稳定的。雌蜗牛的生殖形态在对映异型之间的交配中起着关键作用，特别是因为这群树蜗牛以火对脸的姿势进行交配，这被认为会干扰手间交配。我们发现对形性的进化与生殖形态的分化之间可能存在关联，同时也发现了其他因素的必要性，从而解释了种内亚种中对形性的缺失和存在，这表明生殖形态没有差异。

The purposes of this project was to explore the maintenance mechanism of enantiomorphy and the process of its evolutionary divergence in tree snails, with main focus on the functions and divergence of the traits responsible for the dynamic equilibrium of enantiomorphy. The proximate subjects were to continue long-term surveys of morph frequencies and to evaluate the relative copulation frequencies of the enantiomorphs. We also tested the phylogenetical hypothesis of the evolution of genitalia We discovered the unexpectedly successful copulation between the enantiomorphs the wild It is fist behavioral evidence that negative frequency dependent selection may maintain enantiomorphy. Our molecular phylogeny suggested that enantiomorphy has persisted in the genus Amphidromus for at least one million generations and thus enantiomorphy is evolutionarily stable. lb genital morphology must play a key role for copulation between the enantiomorphs, especially because this groups of tree snails perform copulation in fire-to-face position, which has been expected to interfere interchiral copulation. We found possible correlation between the evolution of enantiomorphy with the divergence of genital morphology and also the necessity of additional factor, to explain the absence and presence of enantiomorphy in subspecies within species that indicate no difference in genitalia.