孔雀鱼的雌雄（亲缘）关系与雄性生殖投资模式

Inbreeding can cause reductions in fitness, driving the evolution of pre- and postcopulatory inbreeding avoidance mechanisms. There is now considerable evidence for such processes in females, but few studies have focused on males, particularly in the context of postcopulatory inbreeding avoidance. Here, we address this topic by exposing male guppies (Poecilia reticulata) to either full-sibling or unrelated females and determining whether they adjust investment in courtship and ejaculates. Our results revealed that males reduce their courtship but concomitantly exhibit short-term increases in ejaculate quality when paired with siblings. In conjunction with prior work reporting cryptic female preferences for unrelated sperm, our present findings reveal possible sexually antagonistic counter-adaptations that may offset postcopulatory inbreeding avoidance by females.

近亲交配会导致适合度降低，从而推动交配前和交配后近亲交配避免机制的进化。现在有相当多的证据表明在雌性中存在这样的过程，但很少有研究集中在雄性身上，特别是在交配后避免近亲交配的背景下。在这里，我们通过将雄性孔雀鱼(Poecilia Reraphata)暴露给完全同胞（兄弟姐妹）或无关的雌性孔雀鱼来验证这个问题，并确定它们是否调整了求爱和射精的投资。我们的结果显示，当与兄弟姐妹配对时，雄性减少了求爱，但同时表现出射精质量的短期增加。结合先前报告的雌性对无关（无亲缘关系）精子的隐秘偏好，我们目前的发现揭示了可能的性对抗反适应，这可能抵消雌性交配后近亲繁殖的避免。

Fitzpatrick, L. J., et al. (2014). "Male-female relatedness and patterns of male reproductive investment in guppies." Biol Lett 10(5): 20140166.