Endemism and invasion in the speciation and polymorphism of snails and slugs

入侵的蜗牛和蛞蝓造成了世界范围内的问题，无论是对作物的直接损害，还是作为农场动物疾病的中间媒介。然而，蜗牛和蛞蝓很难识别，我们也不知道是什么影响了它们的物种形成。因此，该项目的目的将是研究蜗牛的物种形成过程，使用来自英国和其他目标国家的适当代表性物种。具体来说，如果最终目标是了解外部环境和基因如何相互作用以形成适应性变异，那么必须准确地定义外显型。学生将开发方法来定义和量化个体和群体在不同空间尺度上的多态性，同时考虑到鸟类捕食者的视觉灵敏度和更一般的环境。高斯混合模型（Mclust in R）将用于客观地描述变体的数量，并使用“仅仅明显的差异”来检查鸟类和人类的区别性。然后，输出将用于通知后续目标。虽然大部分工作将以实验室为基础，并附带生物信息学元素，但实地收集将是必要的组成部分，包括可能的国外实地工作。

Invasive snails and slugs are causing worldwide problems, both in terms of direct damage to crops, and as intermediate vectors for diseases of farm animals. Yet, snails and slugs are difficult to identify and we have little idea of what influences their speciation. The aim of this project, therefore, will be to study the process of speciation in snails, using appropriate representative species from the UK one other target country. Specifically, if the ultimate aim is to understand how the external environment and genetics interact to shape adaptive variation, then the outward phenotype must be defined accurately. The student will develop methods to define and quantify the polymorphism in individuals and in populations at different spatial scales, taking into account the visual acuity of bird predators and the more general environment. Gaussian mixture modelling (Mclust in R) will be used to characterise the number of morphs objectively, and examine discriminability by birds and humans using "just noticeable differences". The output will then be used to inform subsequent objectives.Although much of the work will be lab-based, with a concomitant bioinformatics element, field collection will be a necessary component, including probable foreign field work.