Understanding Dispersal Polymorphisms in Insects

分散多态性（在同一种群中出现迁移和不飞行的形式）是昆虫中普遍存在的现象。对于包括飞虱（同翅目：飞虱科）在内的大多数昆虫来说，与不会飞行的雌性相比，迁徙的雌性繁殖力降低，产卵时间推迟，这证明了与传播能力相关的生殖成本。对于雄性来说，关于扩散能力和繁殖成功之间关系的相关信息实际上是缺失的。因此，我们对进化、维持和种群分布能力变化的理解几乎完全基于雌性。未能确定雄性翅膀形态之间的适合度差异挑战了我们目前对分散多态性存在的生态和进化基础的认识。飞虱交配系统的几个特征表明，雄性飞虱的迁徙能力存在成本，迁徙和无飞行的雄性飞虱在不同密度下对种群动态的贡献是不同的。本文概述的研究旨在阐明迁徙和无飞行的雄性飞虱在以下方面的内在差异：1)竞争能力（雄性/雄性互动、寻找配偶的能力、对雌性的吸引力、2）生存能力、分散倾向、交配能力、3)不同密度条件下的交配成功率及其对种群增长的贡献。本研究将为更一般的假设（包括雄性和雌性）的发展提供经验基础，以检验昆虫中广泛存在的分散多态性现象。

Dispersal polymorphism (the occurrence of migratory and flightless forms in the same population) is a widespread phenomenon among insects. For most insects including planthoppers (Homoptera: Delphacidae), there is a reproductive cost associated with dispersal ability as evidenced by the reduced fecundity and delayed oviposition of migratory compared to flightless females. Corresponding information for males on the relationship between dispersal ability and reproductive success is virtually absent. As a result, our understanding of the evolution, maintenance, and population consequences of variation in dispersal capability is based almost exclusively on females. Failure to establish fitness differences between male wing forms challenges our current knowledge of the ecological and evolutionary basis for the existence of dispersal polymorphisms. Several characteristics of planthopper mating systems suggest the presence of costs associated with migratory ability in males and that migratory and flightless males contribute differentially to population dynamics at different densities. The research outlined herein seeks to elucidate intrinsic differences between migratory and flightless males of the planthopper Prokelisia dolus in their 1) competitive ability (male / male interactions, ability to locate mates, attractiveness to females, 2) survivorship, propensity to disperse, ability to inseminate mates, and 3) mating success and contribution to population growth across a range of density conditions. This research will supply the empirical basis for the development of more general hypotheses (which include both male and females) to examine the widespread phenomenon of dispersal polymorphism in insects.