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. 我之前忘記詢問你是在哪裡看到這個辭 我想到的有三種可能 1.湯瑪斯·卡弗利爾-史密斯（Thomas Cavalier-Smith，1942年10月21日－） 是一位英國演化生物學家及牛津大學動物學系教授。發表過許多原生生物的分類研究， 主要貢獻在於提出六大界來區分真核生物的構想，不過此概念仍具爭議。卡弗利爾-史密斯依據晚近的演化關係研究， 對部分原生生物進行重新歸類，由他所命名的分類群有Chromalveolata、Opisthokonta、Rhizaria與Excavata等。 (加上 Archaeplastida , Amoebozoa) 2.所有加上超的分類都是因為原有分類系統中沒有這個分類 造成要歸類時的問題 例如已經滅絕的古生物 要放到現有的分類系統 就必須將某個分類擴充成 超群 如果是在科的層級以上 目以下 就形成超科 3.蛋白質 superfamily 則是不同的概念 過去大多以序列分類 但是另一派認為應該以結構 還有功能分類 較能反應實際情形 所以很多過去以序列分類的不同家族蛋白 被分到有相似結構的超家族中 總之有超字者乃是新的分類法 表示與過去分類系統之定義不同 --

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