Botany Department, University of British Columbia, Vancouver, B.C, V6T 1Z4, Canada.
Photosynth Res. 2011 Jan;107(1):103-15. doi: 10.1007/s11120-010-9584-2. Epub 2010 Jul 30.
The chromalveolate hypothesis proposed by Cavalier-Smith (J Euk Microbiol 46:347-366, 1999) suggested that all the algae with chlorophyll c (heterokonts, haptophytes, cryptophytes, and dinoflagellates), as well as the ciliates, apicomplexans, oomycetes, and other non-photosynthetic relatives, shared a common ancestor that acquired a chloroplast by secondary endosymbiosis of a red alga. Much of the evidence from plastid and nuclear genomes supports a red algal origin for plastids of the photosynthetic lineages, but the number of secondary endosymbioses and the number of plastid losses have not been resolved. The issue is complicated by the fact that nuclear genomes are mosaics of genes acquired over a very long time period, not only by vertical descent but also by endosymbiotic and horizontal gene transfer. Phylogenomic analysis of the available whole-genome data has suggested major alterations to our view of eukaryotic evolution, and given rise to alternative models. The next few years may see even more changes once a more representative collection of sequenced genomes becomes available.
卡瓦利-史密斯（Cavalier-Smith）提出的有色鞭毛体假说（J Euk Microbiol 46:347-366, 1999）认为，所有含有叶绿素 c 的藻类（不等鞭毛类、甲藻、隐藻和腰鞭毛目）以及纤毛虫、顶复动物门、卵菌门和其他非光合相关的真核生物，都有一个共同的祖先，它通过红藻的二次内共生获得了一个叶绿体。大量来自质体和核基因组的证据支持光合生物谱系的质体起源于红藻，但二次内共生的数量和质体的丧失数量尚未得到解决。这个问题很复杂，因为核基因组是经过很长一段时间获得的基因的马赛克，不仅通过垂直遗传，还通过内共生和水平基因转移。对现有全基因组数据的系统基因组学分析表明，真核生物进化的观点发生了重大改变，并产生了替代模型。一旦获得更具代表性的测序基因组集，未来几年可能会看到更多的变化。
