Evolution of reproductive traits and speciation process : approaches with experimental hybridization, genomic analysis and mathematical models

在这项研究中，我们集中在一个地面甲虫组Ohomopterus在日本，其中包括15种具有显着的种间多样性的生殖器形态。采用数量遗传和QTL定位的方法，分析了两种同翅目地面甲虫生殖器形态种间差异的遗传基础。在数量遗传学分析中，我们推测，造成0。Iwawakianus和0.舞矢山。我们还利用AFLP和微卫星标记对这些物种的F2杂种进行了QTL定位。采用比较的方法分析了生殖器形态与其他生殖性状的进化趋势，发现生殖器形态的夸张与精荚大小和交配时间有关。此外，我们还分析了精子的形态和精子束，可供选择，以提高精子的竞争能力。我们发现了一个d ...更多信息 结果表明，长精束与生殖器官等生殖性状的进化密切相关。生殖器形态的进化被认为是通过性选择在种群内发生的，可能有助于促进物种形成的机械生殖隔离。预计体型差异也会产生类似的影响。利用种间线粒体基因流作为渐渗杂交的指标，我们发现生殖器和身体大小的差异有影响，以防止渐渗杂交。除上述研究外，我们还研究了表皮碳氢化合物（CHC）对配偶识别的影响以及物种间CHC的变化，以探索CHC作为性信息素的潜在作用，使近缘物种能够共存。此外，还研究了不同种类同翅目昆虫交配前后生殖隔离的模式和强度。少

In this study, we have focused on a ground beetle group Ohomopterus in Japan, which consists of 15 species with marked interspecific diversity of genital morphology. We analyzed the genetic basis of interspecific difference in genital morphology between two Ohomopterus ground beetles using a quantitative genetic and QTL mapping approach. In the quantitative genetic analysis, it was inferred that relatively small number of genes produced the large difference in genitalia between 0. iwawakianus and 0. maiyasanus. We also conducted a QTL mapping with F2 hybrids of these species using AFLP and microsatellite markers. We analyzed evolutionary trend of genital morphology in relation to other reproductive traits using a comparative method, and found that exaggeration of genital morphology occurred in association with spermatophore size and copulation time. In addition, we analyzed shape of sperm and sperm-bundles which can be selected for improvement of sperm-competition ability. We found a d … More imorphism of sperm-bundles, i.e. long and short types, in most species and revealed that long sperm bundles have been evolved in association with other reproductive traits including genital parts. The evolution of genital morphology is considered to have occurred within populations through sexual selection and could have contributed to mechanical reproductive isolation which promotes speciation. A similar effect is expected for differentiation in body size. Using interspecific mitochondrial gene flow as an index of intrgressive hybridization, we revealed that differences in genital and body sizes had effect to prevent introgressive hybridization. Besides the above studies, we also studied the effect of cuticular hydrocarbon (CHC) on mate recognition and variation in CHC among species to explore the potential role of CHC as sexual pheromones to enable coexistence of closely related species. In addition, the pattern and strength of pre-and post-mating reproductive isolation between various pairs of Ohomopterus species. Less