Mitogenomic analyses provide new insights into cetacean origin and evolution
Mitogenomic analyses provide new insights into cetacean origin and evolution
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DOI：
10.1016/j.gene.2004.02.010
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发表时间：
2004-05-26
期刊：
影响因子：
3.5
通讯作者：
Janke, A
中科院分区：
文献类型：
--
作者：
Arnason, U;Gullberg, A;Janke, A
鲸目动物（鲸、海豚、鼠海豚）的进化，长期以来一直吸引着进化生物学家的注意。在这里，我们研究鲸目动物的系统发育关系的基础上分析的完整的线粒体基因组，代表所有现存的鲸目动物的家庭。研究结果表明，现代鲸类的祖先在距今3000 - 3500万年前经历了爆炸性的进化辐射。在这一时期，现存的鲸类动物分为两个主要群体，须鲸（Mysticeti）和齿鲸（Odontoceti）。在这个基础分裂后不久，齿鲸类分化成四个现存的谱系，抹香鲸，突吻鲸，印度河海豚和海豚类（iniid河海豚，独角鲸/白鲸，鼠海豚和真海豚）。目前的数据集允许测试两个最近的形态学假说鲸目动物的起源。其中一种假设认为偶蹄目和鲸类起源于已灭绝的中甲类，另一种假设认为中甲/鲸类是偶蹄目的姐妹群。目前的结果与这两种假设都不一致。研究结果表明，中甲和鲸类之间所声称的形态相似性是进化趋同的结果，而不是共同的祖先。(C)2004 Elsevier B. V.保留所有权利。
The evolution of the order Cetacea (whales, dolphins, porpoises) has, for a long time, attracted the attention of evolutionary biologists. Here we examine cetacean phylogenetic relationships on the basis of analyses of complete mitochondrial genomes that represent all extant cetacean families. The results suggest that the ancestors of recent cetaceans had an explosive evolutionary radiation 30-35 million years before present. During this period, extant cetaceans divided into the two primary groups, Mysticeti (baleen whales) and Odontoceti (toothed whales). Soon after this basal split, the Odontoceti diverged into the four extant lineages, sperm whales, beaked whales, Indian river dolphins and delphinoids (iniid river dolphins, narwhals/belugas, porpoises and true dolphins). The current data set has allowed test of two recent morphological hypotheses on cetacean origin. One of these hypotheses posits that Artiodactyla and Cetacea originated from the extinct group Mesonychia, and the other that Mesonychia/Cetacea constitutes a sister group to Artiodactyla. The current results are inconsistent with both these hypotheses. The findings suggest that the claimed morphological similarities between Mesonychia and Cetacea are the result of evolutionary convergence rather than common ancestry. (C) 2004 Elsevier B.V. All rights reserved.