Phylogenetic relationships and evolutionary patterns of the order Collodaria (Radiolaria).
Phylogenetic relationships and evolutionary patterns of the order Collodaria (Radiolaria).
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DOI：
10.1371/journal.pone.0035775
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Takahashi K
中科院分区：
文献类型：
--
作者：
Ishitani Y;Ujiié Y;de Vargas C;Not F;Takahashi K
射放射虫是唯一一个拥有殖民生活方式的群体。这一群体可能是贫营养海洋中最重要的浮游生物，因为它的生物量大，初级生产力高，与细胞或群体内的许多共生体有关。因此，胶体虫的进化可能与古生产力的变化有关，这些变化影响了贫营养海洋中有机碳的固定。然而，胶子虫的化石记录不足以追踪它们在地质时期的丰度，因为大多数胶子虫没有硅化的外壳。最近，基于核小亚单位核糖体DNA（SSU rDNA）的分子系统学研究证实了胶盘虫属是放射虫属的5个目之一，但由于分类取样不足，胶盘虫之间的关系至今仍未得到解决。我们的系统发育分析揭示了四个新的cololdarians序列，在此基础上cololdarians可以分为四个分支，对应于在家庭水平上的分类分组：Thalassicollidae，Collozoidae，Collosphaeridae，和Collophidae。我们的系统发育分析的结果与每个胶棉家庭的形态特征的比较表明，第一个祖先胶棉有一个孤独的生活方式，没有留下二氧化硅存款。根据分子分歧计算估计的事件发生时间表明，裸胶壳动物谱系首次出现在大约4560万年前，与远洋海洋中硅藻的多样化相一致。殖民胶体虫是在现代海洋环流系统形成和赤道太平洋贫营养条件发展之后出现的。33.4 Ma ago）.殖民地胶体的分歧可能导致在这一时期的初级生产效率的转变。
Collodaria are the only group of Radiolaria that has a colonial lifestyle. This group is potentially the most important plankton in the oligotrophic ocean because of its large biomass and the high primary productivity associated with the numerous symbionts inside a cell or colony. The evolution of Collodaria could thus be related to the changes in paleo-productivity that have affected organic carbon fixation in the oligotrophic ocean. However, the fossil record of Collodaria is insufficient to trace their abundance through geological time, because most collodarians do not have silicified shells. Recently, molecular phylogeny based on nuclear small sub-unit ribosomal DNA (SSU rDNA) confirmed Collodaria to be one of five orders of Radiolaria, though the relationship among collodarians is still unresolved because of inadequate taxonomic sampling. Our phylogenetic analysis has revealed four novel collodarian sequences, on the basis of which collodarians can be divided into four clades that correspond to taxonomic grouping at the family level: Thalassicollidae, Collozoidae, Collosphaeridae, and Collophidae. Comparison of the results of our phylogenetic analyses with the morphological characteristics of each collodarian family suggests that the first ancestral collodarians had a solitary lifestyle and left no silica deposits. The timing of events estimated from molecular divergence calculations indicates that naked collodarian lineages first appeared around 45.6 million years (Ma) ago, coincident with the diversification of diatoms in the pelagic oceans. Colonial collodarians appeared after the formation of the present ocean circulation system and the development of oligotrophic conditions in the equatorial Pacific (ca. 33.4 Ma ago). The divergence of colonial collodarians probably caused a shift in the efficiency of primary production during this period.
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影响因子：
3.3
作者：
Hugall, Andrew F.;Lee, Michael S. Y.
通讯作者：
Lee, Michael S. Y.
影响因子：
1.9
作者：
Anderson, OR;Gastrich, MD;Zettler, LA
通讯作者：
Zettler, LA
影响因子：
2.6
作者：
ANDERSON, OR
通讯作者：
ANDERSON, OR
影响因子：
1.9
作者：
ANDERSON, OR
通讯作者：
ANDERSON, OR
DOI：
10.1016/j.palaeo.2005.07.014
发表时间：
2006-01-30
影响因子：
3
作者：
Funakawa, S;Nishi, H;Nigrini, CA
通讯作者：
Nigrini, CA