台灣地區兩種葉鼻蝠科蝙蝠之遺傳變異

外文標題: 
Genetic variation of two hipposiderid bats (Hipposideros terasensis and Coelops frithi formosanus) in Taiwan
校院系所: 
東海大學生命科學系
指導教授: 
林良恭
出版年份: 
2006年
主題類別: 
摘要: 

物種的族群遺傳結構受到近期及過去族群歷史等因素影響,族群的拓殖過程以及近期的基因交流程度將使族群各自形成不同之遺傳結構。過去研究顯示台灣地區低海拔物種常因中央山脈隔離而有族群分化之現象,但具有飛行能力之蝙蝠其遺傳變異應與其他地棲動物不同。本研究以粒線體DNA D-loop片段檢驗同屬葉鼻蝠科但具不同飛行能力及群集數量的台灣葉鼻蝠與無尾葉鼻蝠之族群遺傳變異。
遺傳變異之結果顯示台灣葉鼻蝠的變異程度極低,但分布最廣的兩大單型間有明顯的地理分布區隔,推測族群拓殖進入台灣時經歷奠基者效應,並產生族群快速擴張。而其顯著之地理結構則可能是由大陸地區經由兩次拓殖事件所造成,並由於雌性個體對出生地之偏好使兩主要單型間僅有低度基因交流。在無尾葉鼻蝠部分,各採集點的單型分布幾乎沒有重疊且彼此間差異大,顯示每一群集皆有其獨有之單型,群集間亦存在顯著之地理結構,且族群分化程度與地理距離呈正比,推測為族群不連續分布以及飛行能力較弱導致群集間基因交流受限之結果。

外文摘要: 

Genetic structure of a species is associated with historical and recent events, such as gene flow and colonization processes. Studies on terrestrial populations in the low elevation areas of Taiwan show that genetic differentiations are based on barriers provided by the Central Mountain Range. The pattern of genetic structures in bats may differ from other terrestrial mammals because of their ability to fly. I examined genetic variations of the mitochondrial D-loop segments of two hipposiderid bats, Hipposideros terasensis and Coelops frithi formosanus. These two species differ in flight ability and population size.
Extremely low genetic variation was found in H. terasensis. Two major haplotypes were widely distributed in distinct areas. This species underwent a founder effect when colonizing Taiwan, followed by rapid population expansion. This significant (chi-square test, P< 0.0001) geographical population structure may have been caused by two colonizations from mainland China. The low gene flow between the two haplotypes suggested female philopatry. In C. f. formosanus, haplotypes were highly variable and did not overlap among sampling localities. There were unique haplotypes for each colony. This suggested significant (chi-square test, P< 0.0001) geographical population structure and isolation-by-distance. This restricted gene flow was caused by discontinued distribution and the bat’s tendency for slow flight over short distances.