Smothers J F, von Dohlen C D, Smith L H, Spall R D
Department of Biological Sciences, Idaho State University, Pocatello 83209.
Science. 1994 Sep 16;265(5179):1719-21. doi: 10.1126/science.8085160.
The evolutionary origins of the protistan phylum, Myxozoa, have long been questioned. Although these obligate parasites are like protozoans in many features, several aspects of their ontogeny and morphology have implied a closer relationship to metazoan lineages. Phylogenetic analyses of 18S ribosomal RNA sequences from myxozoans and other eukaryotes, with the use of parsimony, distance, and maximum-likelihood methods, support the hypothesis that myxozoans are closely related to the bilateral animals. These results suggest that the Myxozoa, long considered an assemblage of protozoans, should be considered a metazoan phylum.
原生动物门粘体动物的进化起源长期以来一直受到质疑。尽管这些专性寄生虫在许多特征上类似于原生动物，但它们个体发育和形态的几个方面暗示了与后生动物谱系有更密切的关系。利用简约法、距离法和最大似然法对粘体动物和其他真核生物的18S核糖体RNA序列进行系统发育分析，支持了粘体动物与两侧对称动物密切相关的假说。这些结果表明，长期以来被认为是原生动物集合的粘体动物门，应该被视为一个后生动物门。
