已灭绝的有袋动物狼的DNA原型
R H Thomas1, W Schaffner, A C Wilson
1Department of Biochemistry, University of California, Berkeley 94720.
Nature
|August 10, 1989
概括
已灭绝的有袋动物狼 (Thylacinus cynocephalus) 基于线粒体DNA分析,与澳大利亚有袋动物比南美有袋动物更为密切相关. 这一发现澄清了它的进化历史,并突出了与其他物种的融合进化.
科学领域:
- 进化生物学是进化的生物学.
- 古生物学的古生物学
- 遗传学 是一个遗传学.
背景情况:
- 已灭绝的有袋动物狼 (Thylacinus cynocephalus) 的遗传位置一直受到争议,形态学研究表明它与南美和澳大利亚的食肉有袋动物有关.
- 以往基于白蛋白抗原性的研究也提供了洞察力,但并没有最终解决鱼的进化关系.
研究的目的:
- 用分子数据确定袋鼠狼的精确遗传归属.
- 为了研究Thylacinus cynocephalus和现存的有袋动物群体之间的进化关系.
主要方法:
- 从袋鼠狼的博物馆标本中直接测序了线粒体 (mt) DNA 的 219 个基对.
- 获得的DNA序列与六种现存的有袋动物属的DNA序列进行比较.
主要成果:
- 线粒体DNA序列数据表明,有袋动物狼与澳大利亚有袋动物食肉动物更为密切相关.
- 这些遗传发现与之前对专蛋白的免疫学研究一致.
- 结果表明,与南美食肉 marsupials 的形态相似之处是趋同进化的例子.
结论:
- 袋鼠狼 (Thylacinus cynocephalus) 在遗传学上是澳大利亚袋鼠的巢穴.
- 它与南美波里亚类的相似之处归因于融合进化,而不是密切的亲属关系.
- 这项研究阐明了一个标志性的灭绝的有袋动物的进化历史.
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