自然杂交与物种形成

doi:10.17520/biods.2017041

摘要/Abstract

摘要：

在生物进化过程中, 自然杂交对物种形成有着重要的影响。多倍化和同倍体杂交物种形成是通过杂交产生新种的两种主要方式。普遍的观点认为多倍化是植物物种形成的主要动力, 而越来越多染色体倍性相同物种之间杂交现象的发现, 说明同倍体杂交也是物种形成的重要方式。目前按严格标准确定的同倍体物种形成案例相对较少, 还亟需对更多不同类型的种间杂交带进行形态与分子等多方面证据的调研, 并通过模型预测与实测数据分析, 来探讨杂交物种形成初期乃至整个过程的遗传基础; 更多杂交物种形成的新模式材料, 有待于通过分化谱系的历史基因流重建进行鉴定, 用于进一步阐释自然选择对于生殖隔离形成的影响、物种形成过程中的生态适应变化和多样性遗传创新的产生规律。本文简要综述了自然杂交的研究历史, 阐述其相关概念、研究方法和基因组时代杂交与物种形成研究的最近进展, 并针对拟解决的关键问题提出相应的分析见解, 以期为后续研究和涉及杂交的物种多样性保护提供借鉴。

关键词: 自然杂交, 物种形成, 多倍化, 同倍体杂交, 渐渗杂交

Abstract

Natural hybridization plays a pivotal role in the formation of new species during the evolution of organisms. There are two principal types of hybrid speciation: polyploidization and homoploid hybrid speciation. The former has been regarded as an important force driving plant speciation, whereas the latter has proved to be a main mode of speciation based on an increasing number of cases, which have reported successful crosses between the species at the same ploidy level. However, only a few cases of homoploid hybrid speciation have been documented when strict criteria are applied. Therefore, molecular evidence involving more genomic loci and morphological investigations from different kinds of hybrid zones, as well as assessments of existing speciation models and new computer stimulations, are required for further understanding the genetic basis of the initial and entire process of speciation. Through the historical reconstruction of gene flow between diverging lineages, additional organismal models for hybrid speciation need to be developed to reveal the effects of natural selection on the formation of reproductive isolation, and to discern the ecologically adaptive changes and the formation rules of novel diversity in the process of hybrid speciation. Here I briefly review the history of studies examining natural hybridization and speciation to introduce concept changes, research methods, and the latest advances of natural hybridization and speciation, to identify the unsolved core and basic scientific questions and to provide feasible suggestions for future studies and the protection of biodiversity involved in natural hybridization.

Key words: natural hybridization, speciation, polyploidization, homoploid hybrid speciation, introgressive hybridization

王玉国 (2017) 自然杂交与物种形成. 生物多样性, 25, 565-576. DOI: 10.17520/biods.2017041.

Yuguo Wang (2017) Natural hybridization and speciation. Biodiversity Science, 25, 565-576. DOI: 10.17520/biods.2017041.

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https://www.biodiversity-science.net/CN/Y2017/V25/I6/565

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