Nishizawa Hideaki, Okuyama Junichi, Kobayashi Masato, Abe Osamu, Arai Nobuaki
Department of Social Informatics, Graduate School of Informatics, Kyoto University, Kyoto, Japan.
Zoolog Sci. 2010 Jan;27(1):14-8. doi: 10.2108/zsj.27.14.
Mitochondrial DNA sequence polymorphisms and patterns of genetic diversity represent the genealogy and relative impacts of historical, geographic, and demographic events on populations. In this study, historical patterns of population dynamics and differentiation in hawksbill (Eretmochelys imbricata) and green turtles (Chelonia mydas) in the Pacific were estimated from feeding populations in the Yaeyama Islands, Japan. Phylogenetic relationships of the haplotypes indicated that hawksbill and green turtles in the Pacific probably underwent very similar patterns and processes of population dynamics over the last million years, with population subdivision during the early Pleistocene and population expansion after the last glacial maximum. These significant contemporary historical events were suggested to have been caused by climatic and sea-level fluctuations. On the other hand, comparing our results to long-term population dynamics in the Atlantic, population subdivisions during the early Pleistocene were specific to Pacific hawksbill and green turtles. Therefore, regional differences in historical population dynamics are suggested. Despite limited sampling locations, these results are the first step in estimating the historical trends in Pacific sea turtles by using phylogenetics and population genetics.
线粒体DNA序列多态性和遗传多样性模式反映了历史、地理和人口事件对种群的谱系及相对影响。在本研究中，从日本八重山群岛的觅食种群中估算了太平洋玳瑁（蠵龟）和绿海龟的种群动态和分化的历史模式。单倍型的系统发育关系表明，太平洋的玳瑁和绿海龟在过去一百万年中可能经历了非常相似的种群动态模式和过程，在更新世早期种群细分，在末次盛冰期后种群扩张。这些重大的当代历史事件被认为是由气候和海平面波动引起的。另一方面，将我们的结果与大西洋的长期种群动态进行比较，更新世早期的种群细分是太平洋玳瑁和绿海龟所特有的。因此，提示了历史种群动态存在区域差异。尽管采样地点有限，但这些结果是利用系统发育学和种群遗传学估算太平洋海龟历史趋势的第一步。
