Sogin M L, Elwood H J, Gunderson J H
Proc Natl Acad Sci U S A. 1986 Mar;83(5):1383-7. doi: 10.1073/pnas.83.5.1383.
The small-subunit rRNA gene sequences of the flagellated protists Euglena gracilis and Trypanosoma brucei were determined and compared to those of other eukaryotes. A phylogenetic tree was constructed in which the earliest branching among the eukaryotes is represented by E. gracilis. The E. gracilis divergence far antedates a period of massive evolutionary radiation that gave rise to the plants, animals, fungi, and certain groups of protists such as ciliates and the acanthamoebae. The genetic diversity in this collection of eukaryotes is seen to exceed that displayed within either the eubacterial or the archaebacterial lines of descent.
测定了鞭毛原生生物纤细裸藻和布氏锥虫的小亚基核糖体RNA基因序列，并与其他真核生物的序列进行了比较。构建了一个系统发育树，其中真核生物中最早分支的是纤细裸藻。纤细裸藻的分化远远早于导致植物、动物、真菌以及某些原生生物群体（如纤毛虫和棘阿米巴）的大规模进化辐射时期。在这组真核生物中观察到的遗传多样性超过了在真细菌或古细菌谱系中所显示的遗传多样性。
