Understanding Dispersal Polymorphisms in Insects

扩散多态(在同一种群中出现迁徙和不能飞行的形式)是昆虫中普遍存在的现象。对于包括飞虱(同翅目：飞蝇科)在内的大多数昆虫来说，与扩散能力相关的繁殖成本，表现为与不会飞的雌性相比，迁徙的雌性昆虫的繁殖力降低和产卵延迟。对于雄性来说，关于扩散能力和繁殖成功之间的关系的相应信息几乎是缺乏的。因此，我们对扩散能力变异的进化、维持和种群后果的理解几乎完全建立在雌性的基础上。未能确定雄性翅型之间的适合度差异，挑战了我们目前对扩散多态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，与雄性迁徙能力相关的成本存在，迁徙和不会飞的雄性在不同密度下对种群动态的贡献是不同的。在此概述的研究试图阐明在1)竞争能力(雄/雄相互作用、寻找配偶的能力、对雌性的吸引力)、2)生存能力、分散倾向、授精能力和3)在一系列密度条件下的交配成功和对种群增长的贡献方面，迁飞的和不会飞的雄性之间的内在差异。这项研究将为建立更普遍的假说(包括雄性和雌性)提供经验基础，以检验昆虫中普遍存在的扩散多态现象。

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.