臺灣地區草蜥類生物地理類緣關係之研究

Abstract

本研究是以同功酵素(isozyme)電泳技術(electrophoretic technique)，對台灣地區蜥蜴科(Lacert­idae)草蜥屬(Takydromus)之蓬萊草蜥(Takydromus stejnegeri)、南台草蜥(Takydromus sauteri)、台灣草蜥(Takydromus formosanus)、雪山草蜥(Takydromus hsuehshanensis)和台灣地蜥(Takydromus kuehnei)等五種草蜥進行遺傳結構(genetic structure)與生物地理類緣關係(phylogeography)的探討。此外，使用馬祖之北草蜥(Takydromus septentrionalis)及香港的南草蜥(Takydromus sexlineatus)作為外群(out­group)生物，進行比對。 實驗中共檢測了十五種同功酵素，得到26個基因座(locus)，73個對偶基因(allele)。其中，台灣五種草蜥與外群(兩種)彼此種間共測得24個多型性基因座(polymorphic)，平均多型性基因座比例為18.801%；每一個基因座之平均對偶基因數為1.28；平均觀測異質度(Ho)為0.047，平均理論異質度(He)為0.073。在台灣所產之五種草蜥中，蓬草草蜥與雪山草蜥的遺傳距離[Nei(1978)]最近[Nei's(D)=0.174]，而台灣地蜥與台灣草蜥最遠[Nei's(D)=0.733]。種間呈現極高度的遺傳分化(FST=0.76)。遺傳距離資料顯示，台灣五種草蜥為同一屬中之獨立種。由階層分析(hierarchy analysis)可知，五種草蜥種間遺傳變異達到52.7%。種間之群叢樹狀圖將台灣五種草蜥分成類緣關係較遠的兩群：1.地蜥群((Platyplacopus grou)，色括台灣地蜥及南台草蜥；2草蜥群(Takydromus group)，包括蓬草草蜥、雪山草蜥及台灣草蜥。此外，依實驗結果顯示：在馬祖所採之北草蜥應屬於草蜥群，而來自香港的南草蜥則是屬於地蜥群。 台灣五種草蜥與中國大陸草蜥屬的演化歷程，及地蜥群和草蜥群在台灣地區擴散的方向，仍須更多詳細的資料進行研究。

In this research, we used electrophoretic technique of isozyme to survey the genetic structure and the phylogeography among Takydromus stejnegeri, Takydromus sauteri, Takydromus formosanus, Takydromus hsuehshanensis, and Takydromus kuehnei in Taiwan. Takydromus septentrionalis from Ma-Zu and Takydromus sexlineatus from Hong Kong were used as outgroup species animals. Among five species of the Lacertidae in Taiwan and two outgroup, 24 loci were polymorphic, proportion of poly-morphic loci was 18.801%, average number of alleles per locus was 1.28, mean observed heterozygosity of per locus was 0.047, and mean expected heterozygosity of per locus was 0.073. The smallest Nei's (1978) genetic distance between T. stejnegeri and T. hsuehshanensis was [Nei's(D)=0.174], and the largest was found between T. kuehnei and T. formosanus [Nei's(D)=0.733]. The five species of the Lacertidae were independent species of the same genus. The tree of UPGMA among 5 species had two clusters which were phylogenetically closer: 1. Platyplacopus group, including T. kuehnei and T. sauteri. 2. Takydromus group, including T. stejnegeri . T. hsuehshanensis and T. formosanus. In addition, T. septentrionalis and T. sexlineatus were subordinated to Takydromus group and Platyplacopus group, respectively. The correlation of evolution between Takydromus spp. of Taiwan and mainland China, and the dispersive direction of Platyplacopus group and Takydromus group in Taiwan still need more detailed studies for further understanding.