Systematic Biology Program, Department of Organismal Biology, Evolutionary Biology Centre, Norbyvägen 18 D, Uppsala, Sweden.
PLoS One. 2013 Sep 11;8(9):e74374. doi: 10.1371/journal.pone.0074374. eCollection 2013.
Evolution of lineage diversification through time is an active area of research where much progress has been made in the last decade. Contrary to the situation in animals and plants little is known about how diversification rates have evolved in most major groups of protist. This is mainly due to uncertainty about phylogenetic relationships, scarcity of the protist fossil record and the unknown diversity within these lineages. We have analyzed the evolutionary history of the supergroup Amoebozoa over the last 1000 million years using molecular dating and species number estimates. After an origin in the marine environment we have dated the colonization of terrestrial habitats by three distinct lineages of Amoebozoa: Dictyostelia, Myxogastria and Arcellinida. The common ancestor of the two sister taxa, Dictyostelia and Myxogastria, appears to have existed before the colonization of land by plants. In contrast Arcellinida seems to have diversify in synchrony with land plant radiation, and more specifically with that of mosses. Detection of acceleration of diversification rates in Myxogastria and Arcellinida points to a co-evolution within the terrestrial habitats, where land plants and the amoebozoans may have interacted during the evolution of these new ecosystems.
随着时间的推移，谱系多样化的进化是一个活跃的研究领域，在过去十年中取得了很大进展。与动物和植物的情况相反，人们对大多数原生生物主要类群的多样化率如何进化知之甚少。这主要是由于系统发育关系的不确定性、原生生物化石记录的稀缺以及这些谱系内部未知的多样性。我们使用分子定年法和物种数量估计分析了过去 10 亿年来超群体变形虫的进化历史。在海洋环境中起源后，我们确定了三个不同的变形虫谱系：Dictyostelia、Myxogastria 和 Arcellinida 已经殖民到陆地栖息地。Dictyostelia 和 Myxogastria 两个姐妹分类群的共同祖先似乎存在于植物殖民陆地之前。相比之下，Arcellinida 似乎与陆地植物辐射同步多样化，更具体地说，与苔藓植物的辐射同步多样化。在 Myxogastria 和 Arcellinida 中检测到多样化率的加速，表明在陆地栖息地中存在共同进化，在这些新生态系统的进化过程中，陆地植物和变形虫可能相互作用。
