印度西太平洋三帶圓雀鯛的親緣地理關係及遺傳結構

Phylogeography and genetic structure of Dascyllus aruanus in Indo-West Pacific Ocean

張鳳婷(Feng-Ting Chang)

指導教授 ： 戴昌鳳

共同指導教授 ： 陳韋仁(Wei-Jen Chen)

國立臺灣大學/理學院/海洋研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.00943

摘要

三帶圓雀鯛（Dascyllus aruanus）為廣泛分佈於印度、太平洋的珊瑚礁魚類，其範圍北起日本、南至澳大利亞、西自紅海和東非、東至法屬玻里尼西亞（French Polynesia）。本研究樣本採集自十三個地點，包括印度洋區的紅海與馬達加斯加島周圍四個地點，以及太平洋區的臺灣、印尼、日本、西沙、東沙、菲律賓、新卡里多尼亞（New Caledonia）與法屬玻里尼西亞，共260隻個體。以粒線體cytochrome b（1040-bp）基因及7個微衛星DNA基因座為分子標誌，分析族群之間的遺傳多樣性及親緣地理，並檢驗印度、太平洋族群分化及邊緣族群遺傳變異較低的假說。根據粒線體cytochrome b基因所得到的分子親緣樹，印度洋區的五個族群自成一單系群，太平洋區族群則混雜在一起，雖然親緣樹上的分群並無高支持度，但從單型的最小擴張枝樹（minimium spanning tree）可知，印度洋與太平洋的三帶圓雀鯛族群間並無共有的單型，顯示印度洋和太平洋族群之間有明顯的親緣地理結構。在法屬玻里尼西亞的25隻個體中，有23隻個體自成兩個單系群，另有2隻個體與其他太平洋族群混雜在一起，這些少數個體可能為逢機事件所造成。遺傳多樣性的分析結果顯示，法屬玻里尼西亞與紅海的族群具有較低單型歧異度與低核苷酸歧異度等特徵，符合邊緣族群的遺傳特性；其餘族群則具有較高的遺傳多樣性，顯示這些族群間可能有頻繁的基因交流。

關鍵字

三帶圓雀鯛 ； 親緣地理 ； 遺傳多樣性 ； 族群結構 ； 印度太平洋屏障

並列摘要

Dascyllus aruanus is distributed throughout the Indo-Pacific Ocean, from Red Sea and East Africa to French Polynesia, and from southern Japan to southeast Australia in West Pacific. The aims of this study were to reveal the phylogeographic relationship and population genetic diversity of D. aruanus in Indo-Pacific by using mtDNA cytochrome b (1040-bp) and 7 microsatellite loci. Totally, 260 individuals were collected from southern Taiwan, Raja Ampat (Indonesia), Okinawa (Japan), Paracel Island (China) and Dongsha Atoll in the South China Sea, New Caledonia, Gaohagan Island (Philippines), French Polynesia, Eilat in Red Sea and four locations around Madagascar. The phylogenetic tree of mtDNA showed that populations in Indian Ocean (Madagascar and Red Sea populations) formed a monophyletic group and the rest Pacific populations were mixed together. A strong genetic break between Indian and Pacific populations suggests that the Indo-Pacific barrier may play an important role in shaping their genetic structure. Among the 25 individuals collected from French Polynesia, 23 individuals formed a group with high bootstrap value, while the rest 2 individuals were mixed with other Pacific populations which might be due to rare dispersal events. The lower genetic diversity found in French Polynesia and Red Sea populations fit with the prediction of genetic diversity in peripheral populations. However, the other Pacific populations and four populations around Madagascar were characterized with higher genetic diversity which indicating that high and frequent gene flows may exist among local and regional populations.

並列關鍵字

Dascyllus aruanus ； phylogeography ； genetic diversity ； population structure ； Indo-Pacific Barrier

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