Negative frequency-dependent selection in female color polymorphism of a damselfly.

摘要: Negative frequency-dependent selection (NFDS) is one of the most powerful selective forces maintaining genetic polymorphisms in nature. Recently many prospective cases by NFDS have been reported. Some them are very complicated, although strongly supportive NFDS. Here we investigate wild populations dimorphic damselfly Ischnura senegalensis, which females occur as andromorphs and gynomorphs. Specifically, (1) test fitness responses to morph frequencies, (2) built a simple population model, (3) compare observed predicted morph-frequency dynamics. Fitnesses two morphs an inverse function its own frequency population, about equal when their frequencies similar. Thus conditions necessary for satisfied. The long-term field surveys show that oscillate with period generations. Morph small undergo large oscillations whereas those do oscillations. demographic properties dynamics agree well our model. This example simplest confirmed