Correlated divergence of female and male genitalia in replicated lineages with ongoing ecological speciation

Divergence of genital traits among lineages has the potential to serve as a reproductive isolating barrier when copulation, insemination, or fertilization are inhibited by incompatibilities between female and male genitalia. Despite widespread evidence for genital trait diversity among closely related lineages and coevolution of female and male genitalia within lineages, few studies have investigated genital evolution during the early stages of speciation. We quantified genital variation in replicated population pairs of Poecilia mexicana with ongoing ecological speciation between sulfidic (H2S-containing) and nearby non-sulfidic habitats. These analyses revealed rapid and correlated divergence of female and male genitalia across evolutionarily independent population pairs exposed to divergent selection regimes. Both sexes exhibited convergent evolution of genital traits among populations inhabiting similar habitat types. Our results demonstrate that genital evolution can occur during t...

谱系间生殖器特征的分化有可能成为生殖隔离屏障（reproductive isolating barrier）——当雌雄生殖器间的不兼容性阻碍交配、授精或受精过程时。尽管有大量证据表明近缘谱系间存在生殖器特征多样性，且谱系内雌雄生殖器存在协同进化（coevolution），但很少有研究调查物种形成（speciation）早期阶段的生殖器进化。我们量化了墨西哥花鳉（Poecilia mexicana）重复种群对的生殖器变异，这些种群对正处于硫化（含H₂S）栖息地与邻近非硫化栖息地之间的生态物种形成（ecological speciation）过程中。这些分析揭示，在暴露于不同选择制度（selection regimes）的进化独立种群对中，雌雄生殖器发生了快速且相关的分化。在栖息于相似栖息地类型的种群中，雌雄两性均表现出生殖器特征的趋同进化（convergent evolution）。我们的结果表明，生殖器进化可发生在t...期间。