| Summary: | 碩士 === 國立臺灣師範大學 === 生命科學研究所 === 97 === In this study, I used Microhyla heymonsi (Anura: Microhylidae), a low to mid-altitude distributed narrow-mouth frog in Taiwan to investigate the pattern of phylogeography by using mitochondrial cytochrome oxidaseⅠ(COⅠ) gene. Meanwhile, I also discuss the phylogeographic and the population structure relationship with the historical geological events and dispersal ability of the frog in Taiwan. A total of 181 specimens were collected from 25 populations throughout the island. The results of phylogenetic tree indicated that there are two major haplotype clades in Taiwan. The variation of population genetics of these two clades correspond to the eastern and western geographical features of Central Mountain Range, respectively. Central Mountain Range is a major geographic barrier and disrupt the gene flow between eastern and western populations. Both major clades showed a significant isolation by distance effect. Historical population demography analyzed using neutrality tests, mismatch distribution and Bayesian skyline plot analyses showed that populations of M. heymonsi in Taiwan were undergone an expansion event during Pleistocene Epoch.
M. heymonsi widespreads in South and Southeast Asia. The diversification of frogs among these regions is an interesting subject. Our results suggested that there was substantial genetic differentiation among populations in SE Asia. Because we did not have enough samples of populations in these areas, especially regions of southeast China, so we were unable to discuss the source population of Taiwan, the colonization sequence among populations and retrace the historical demography. If we can increase the sample sizes in distributed areas in the near future, we will be able to interpret the evolutionary history of the widely distributed species.
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