Speciation and species classification of allopatric populations : beyond the DNA barcoding

通过DNA分析、形态学分析和包括鸣声分析在内的生态学分析，对14个陆地鸟类分类群（19种）的异域居群进行了物种形成和分类研究。结果发现，日本列岛及其周边地区陆地鸟类的种群结构和物种形成模式极其多样。也就是说，通过分子分析发现，陆地鸟类的种群结构与琉球群岛的地质历史不一致，每种物种的种群分化模式差异极大。各种地理界线的位置不同，遗传分化程度和种群划分年龄也不同。此外，形态分裂和生态分裂的程度也各不相同，而且一直与遗传分裂的程度不一致。歌曲的进化可能受到相关物种共存或不共存的影响，即歌曲的“特征置换”。从适应行为到人工环境的变化，几乎整个岛屿的养殖，形态适应进化可能会加速。建议对一些物种的亚种（如琉球鸮Otus elegans和水仙Ficedula narcissina）进行重新研究，甚至对一些物种（如Taczanowski's Grasshopper Warbler Locustella pleskei和褐耳bulbulhypsipetes amaurotis）进行重新研究。本项目期间我们只完成了北极林莺（Phylloscopus borealis）和白画眉（White’s Thrush Zoothera dauma）的种和亚种的修订，其他的修订有待于后续的研究。

Researches on speciation and species classification of allopatric populations of 14 land bird taxa(19 species) were conducted through DNA analyses, morphological analyses and ecological analyses including vocal analysis of songs. As the results, extremely various patterns of the population structure and speciation of land birds in and around the Japanese Archipelago were found. That is to say, molecular analyses suggested that the population structures of land bird species discord with the geological history of the Ryukyu Islands, and extremely various patterns of population differentiations at every species are found. Locations of geographical boundary line are various in each species as well as the degree of genetic differentiation and the age of population division. Furthermore, the degree of morphological division and ecological division are also various and they are not concordant with that of genetic division all time. Evolution of songs may be influenced from coexistence or not of the related species, namely it is 'character displacement' of songs. Morphological adaptive evolution may be accelerated from the adaptive behavior to artificial environmental change, cultivation of nearly whole an islet. We suggested the need of reinvestigation to revision of subspecies in several species, e. g. Ryukyu Scops Owl Otus elegans and Narcissus Flycatcher Ficedula narcissina, and even to revision of species in some species, e. g. Taczanowski's Grasshopper Warbler Locustella pleskei and Brown-eared Bulbul Hypsipetes amaurotis. We have finished revision of species and subspecies only in Arctic Warbler Phylloscopus borealis and White's Thrush Zoothera dauma in the period of this research project, thus the other revisions remain to future studies.