Sex Ratio Distorter Reduces Sperm Competitive Ability in an Insect

摘要: Selfish genetic elements (SGEs) are ubiquitous in animals and often associated with low male fertility due to reduced sperm number carriers. In the fruit fly Drosophila pseudoobscura, meiotic driving X chromosome “sex ratio” kills Y-bearing carrier males (SR males), resulting female only broods. We competed SR against ejaculates of noncarrying standard (ST quantified transferred by ST females. show that very poor competitors, which is partly related transfer fewer during mating. However, numbers alone cannot explain observed paternity reduction, indicating males’ may be quality, possibly damage killing Y-sperm. The reduction competitive ability large enough potentially stabilize spread sex ratio drive through populations. coupled their fitness as mates could favor increased remating females reduce males. Given generally performance SGE-carrying competition, this generate strong selective pressure favoring polyandry many species.