期刊
MOLECULAR PHYLOGENETICS AND EVOLUTION
卷 23, 期 2, 页码 137-149出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/S1055-7903(02)00008-8
关键词
scleractinia; mitochondrial 12S ribosomal RNA gene; skeleton; phylogeny
Scleractinian corals have long been assumed to be a monophyletic group characterized by the possession of an aragonite skeleton. Analyses of skeletal morphology and molecular data have shown conflicting patterns of suborder and family relationships of scleractinian corals, because molecular data suggest that the scleractinian skeleton could have evolved as many as four times. Here we describe patterns of molecular evolution in a segment of the mitochondrial (mt) 12S ribosomal RNA gene from 28 species, of scleractinian corals and use this gene to infer the evolutionary history of scleractinians. We show that the sequences obtained fall into two distinct clades, defined by PCR product length. Base composition among taxa did not differ significantly when the two clades were considered separately or as a single group. Overall, transition substitutions accumulated more quickly relative to transversion substitutions within both clades. Spatial patterns of substitutions along the 12S rRNA gene and likelihood ratio tests of divergence rates both indicate that the 12S rRNA gene of each clade evolved under different constraints. Phylogenetic analyses using mt 12S rRNA gene data do not support the current view of scleractinian phylogeny based upon skeletal morphology and fossil records. Rather, the two-clade hypothesis derived from the rut 16S ribosomal gene is supported. (C) 2002 Elsevier Science (USA). All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据