台灣是一個多山的島嶼，海拔1500以上的山區就佔據了全島面積的三分之二，高山生態系是台灣地區生物多樣性最豐富的場所，不但特有比例高且是野生動物保護的重要區域。然高聳的山脈對島上的生物族群擴散形成極大的阻隔，物種可能受到不同山系間的山谷或是分布在山脈中不同的河系所形成的深蝕河谷阻礙，導致無法在各山系間進行擴散而形成被隔離的族群，高山島嶼的特性突出。因此探討高山島嶼對棲地、物種及基因的影響為當今生物多樣性保育研究的重要課題。近來許多台灣高山地區的動物地理親緣關係研究，顯示台灣的高山動物受到冰河期侵入時間與島上複雜地形的影響。田鼠亞科(Microtinae)為溫帶型小型鼠類，台灣高山地區共分佈有兩種即黑腹絨鼠(Eothenomys melanogaster)與高山田鼠(Microtus kikuchii)，分布於海拔2000公尺~3500公尺山區，體型小移動力低，對棲地需求亦特化。對於分布在高海拔的兩物種，其分布是否以形成高山島嶼的型態，族群間的基因交流是否阻斷，是否遺傳分化已形成值得探討。本究計畫將針對各山區內的黑腹絨鼠與高山田鼠，利用分子遺傳標記，比較不同高山地區族群間的遺傳變異。本研究預期成果除將可瞭解不同山脈動物之遺傳組成，並檢視其分類地位，尋求是否有種化存在，並探討二種田鼠類自中國大陸遷入的年代與可能路徑。本研究預期成果提供林務及保育單位進行降低棲地島嶼化效應之保育規劃和教育上的參考。 High mountains have been constituted the specific ecosystems in Taiwan. It is inhibiting the higher species diversity and the important sites for wildlife conservation and research. However, the high mountain range and a number of deep valleys may have interrupted the interactions among wildlife. The information of the habitats, species and genetic differentiation among the conspecific isolating populations should be necessarily studied by means of biodiversity researches. Two species of Microtinae inhibit in the high mountain areas with altitudes 2000 to 3500 meter, i.e. Eothenomys melanogaster and Microtus kikuchii. It provides the best study materials for understanding the genetic structures of animals living in the mountain islands. The objectives of this study are: 1) to determine population genetic differentiation based on the molecular data, 2) to reexamine their taxonomic status and investigate the possibility of speciation, 3) to analyze the invasion route from China among the epoch. On the other hand, the expected results will be built up a complete basic data of the mammalian biodiversity for resource management.
