Department of Biological Sciences and Auburn University Museum of Natural History, Auburn University, Auburn, AL, USA
Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic.
Proc Biol Sci. 2018 Jan 10;285(1870). doi: 10.1098/rspb.2017.1762.
Parallel adaptive radiations have arisen following the colonization of islands by lizards and lakes by fishes. In these classic examples, parallel adaptive radiation is a response to the ecological opportunities afforded by the colonization of novel ecosystems and similar adaptive landscapes that favour the evolution of similar suites of ecomorphs, despite independent evolutionary histories. Here, we demonstrate that parallel adaptive radiations of cichlid fishes arose in South American rivers. Speciation-assembled communities of pike cichlids () have independently diversified into similar suites of novel ecomorphs in the Uruguay and Paraná Rivers, including crevice feeders, periphyton grazers and molluscivores. There were bursts in phenotypic evolution associated with the colonization of each river and the subsequent expansion of morphospace following the evolution of the ecomorphs. These riverine clades demonstrate that characteristics emblematic of textbook parallel adaptive radiations of island- and lake-dwelling assemblages are feasible evolutionary outcomes even in labile ecosystems such as rivers.
鱼类殖民湖泊和蜥蜴殖民岛屿之后，平行适应辐射就出现了。在这些经典例子中，平行适应辐射是对新生态系统殖民化和类似适应性景观所提供的生态机会的一种反应，尽管存在独立的进化历史，但类似的生态型 suites 有利于进化。在这里，我们证明了慈鲷鱼类的平行适应辐射出现在南美洲的河流中。 鲈形目慈鲷（）的物种形成聚集群落已经在乌拉圭河和巴拉那河独立地多样化成类似的新型生态型，包括缝隙食者、附生生物食者和食蜗牛者。与每条河流的殖民化以及随后在生态型进化后形态空间的扩张相关的表型进化发生了爆发。这些河流分支表明，即使在像河流这样不稳定的生态系统中，也有可能产生标志性的岛屿和湖泊聚居组合的平行适应辐射的特征。
