Perspectives on the classification of eukaryotic diversity have changed rapidl\ y in recent years, as the four eukaryotic groups within the five-kingdom class\ ification—plants, animals, fungi, and protists—have been transformed through\ numerous permutations into the current system of six “supergroups.” The int\ ent of the supergroup classification system is to unite microbial and macrosco\ pic eukaryotes based on phylogenetic inference. This supergroup approach is in\ creasing in popularity in the literature and is appearing in introductory biology textbooks. We evaluate the stability \ and support for the current six-supergroup classification of eukaryotes based \ on molecular genealogies. We assess three aspects of each supergroup: (1) the \ stability of its taxonomy, (2) the support for monophyly (single evolutionary \ origin) in molecular analyses targeting a supergroup, and (3) the support for \ monophyly when a supergroup is included as an out-group in phylogenetic studie\ s targeting other taxa. Our analysis demonstrates that supergroup taxonomies are unstable and that support for grou\ ps varies tremendously, indicating that the current classification scheme of e\ ukaryotes is likely premature. We highlight several trends contributing to the\ instability and discuss the requirements for establishing robust clades withi\ n the eukaryotic tree of life. 我之前忘记询问你是在哪里看到这个辞 我想到的有三种可能 1.汤玛斯·卡弗利尔-史密斯（Thomas Cavalier-Smith，1942年10月21日－） 是一位英国演化生物学家及牛津大学动物学系教授。发表过许多原生生物的分类研究， 主要贡献在於提出六大界来区分真核生物的构想，不过此概念仍具争议。卡弗利尔-史密斯依据晚近的演化关系研究， 对部分原生生物进行重新归类，由他所命名的分类群有Chromalveolata、Opisthokonta、Rhizaria与Excavata等。 (加上 Archaeplastida , Amoebozoa) 2.所有加上超的分类都是因为原有分类系统中没有这个分类 造成要归类时的问题 例如已经灭绝的古生物 要放到现有的分类系统 就必须将某个分类扩充成 超群 如果是在科的层级以上 目以下 就形成超科 3.蛋白质 superfamily 则是不同的概念 过去大多以序列分类 但是另一派认为应该以结构 还有功能分类 较能反应实际情形 所以很多过去以序列分类的不同家族蛋白 被分到有相似结构的超家族中 总之有超字者乃是新的分类法 表示与过去分类系统之定义不同 --

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