Macey J R, Schulte J A, Larson A, Fang Z, Wang Y, Tuniyev B S, Papenfuss T J
Department of Biology, Washington University, St. Louis, Missouri 63130, USA.
Mol Phylogenet Evol. 1998 Feb;9(1):80-7. doi: 10.1006/mpev.1997.0440.
Phylogenetic relationships among Tibetan populations of the Bufo bufo species group are investigated using 1063 bases of mitochondrial DNA sequence from the genes encoding ND1 (subunit one of NADH dehydrogenase), tRNA(Ile), tRNA(Gln), tRNA(Met), and ND2. The aligned sequences contain 181 phylogenetically informative characters across all taxa sampled. Two hypotheses for colonization of the Tibetan Plateau are tested. A vicariant hypothesis predicts monophyly of populations from high elevations. A dispersalist hypothesis predicts monophyly of populations in each of two river drainages (Yangtze and Yellow rivers), which requires nonmonophyly of populations from high elevations. Both hypotheses are rejected in favor of a third hypothesis that combines elements of vicariance and dispersal. The most parsimonious phylogenetic tree places the high-elevation species, B. andrewsi, as the sister taxon to the other Asian Bufo populations; these high-elevation populations are postulated to have had a vicariant origin approximately 5 million years before present. The high-elevation population recognized as B. minshanicus is nested within low-elevation populations of B. gargarizans and is suggested to have dispersed onto the Tibetan Plateau more recently.
利用编码ND1（NADH脱氢酶亚基一）、tRNA（Ile）、tRNA（Gln）、tRNA（Met）和ND2的线粒体DNA序列中的1063个碱基，研究了中华蟾蜍物种组西藏种群之间的系统发育关系。比对后的序列在所有采样分类群中包含181个系统发育信息特征。检验了两种关于青藏高原种群定殖的假说。隔离分布假说预测高海拔种群为单系群。扩散分布假说预测两个河流流域（长江和黄河）中每个流域的种群为单系群，这需要高海拔种群不是单系群。两种假说均被否定，支持了一种结合了隔离分布和扩散分布要素的第三种假说。最简约的系统发育树将高海拔物种华西蟾蜍置于其他亚洲蟾蜍种群的姐妹分类单元位置；这些高海拔种群被推测大约在距今500万年前有一个隔离分布起源。被认定为岷山蟾蜍的高海拔种群嵌套在中华大蟾蜍的低海拔种群中，并被认为是最近才扩散到青藏高原的。
