| 摘要: |
| 同域物种形成是指在缺少地理隔离的情况下分化出新种,相比异域物种形成更为罕见,存在较多的研究空白。该文分析了近十年来与被子植物同域物种形成相关的国内外研究,着重论述同域物种形成的影响因素和种对间的生殖隔离。考虑到历史上的地理隔离难以确定,加之种对间亲缘关系很近,同域物种的判定容易引发争议。其成因可分为生态因素和突变因素:生态因素即特殊小生境产生的分化选择压,促使原始群体分化出差异显著的偏好,并借助资源竞争和协同演化不断加强; 突变因素涉及杂交和多倍化,以异源多倍体成种的贡献最大,而同倍体杂交成种和同源多倍体成种虽广泛发生但少见成功案例。生殖隔离是影响物种形成的重要因素之一,可分为前隔离和后隔离,其中以花期隔离和传粉者隔离为主的前隔离起主导作用,而花粉竞争、配子不亲和以及杂种不活、不育和杂种衰退等后隔离会带来高额的生殖成本,从而加速前隔离或自交的演化。同域物种的形成是各方因素共同作用的结果,种间通常同时存在着较强的生殖隔离和一定的基因交流,以生态位竞争为前提,尤其是在充足的分化选择压下,即使基因流较为频繁也能分化形成同域物种。 |
| 关键词: 被子植物, 同域物种形成, 分化选择模型, 生殖隔离 |
| DOI：10.11931/guihaia.gxzw202007006 |
| 分类号: |
| 文章编号:1000-3142(2022)01-0014-11 |
| Fund project:国家自然科学基金(31300558, 32071782); 江苏省基础研究计划项目(BK20130972); 江苏省高校优势学科建设工程资助项目(PAPD); 江苏高校品牌专业建设工程资助项目(TAPP)[National Natural Science Foundation of China(31300558, 32071782); Basis Research Plan Foundation of Jiangsu Province(BK20130972); Priority Academic Program Development of Jiangsu Higher Education Institution(PAPD); Top-notch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP)]。 |
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| Research progress of angiosperms sympatric speciation |
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WANG Zhangpei1,2, CHEN Lin1,2*, WANG Xianrong1,2
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1. Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China;2. College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
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| Abstract: |
| Sympatric speciation means that new species ignore the absence of geographic isolation. Compared with allopatric speciation, there are more blanks that need to be filled because of rarity. This paper analyzes the researches about angiosperms sympatric speciation in the past ten years, and focuses on the origin factors and reproductive isolation. Judging seems to be more difficult because of the uncertain historic geographic and close relationship between related species. The origin can be divided into ecological factors that mean destructive selection from special niches and gene factors that include hybridization and polyploids. The former drives ancestor into subgroups with different preferences and strengthened by resource competition and co-evolution. The latter creates species faster in places where the allopolyploid has most contribution, the homoploid hybrid and autopolyploid seem to be wide, but insignificant to the speciation. Similarly, reproductive isolation can be divided into the prezygotic and the postzygotic. The former plays a leading role, with more important flowering isolation and pollinator isolation, while the pollen competition, gamete incompatibility and the later that includes hybrid defect such as abortion, infertility and decline are slight and will accelerate the evolution of prezygotic as well as selfing because of high reproductive costs. In short, sympatric speciation requires the cooperation of various factors and the reproductive isolation can conexist with gene flow, which is driven by the niche competition. Especially when the destructive selection is strong enough, sympatric speciation can continue even if the gene flow is frequent. |
| Key words: Angiosperms, sympatric speciation, disruptive selection model, reproductive isolation |
