Data from: Island- and lake-like parallel adaptive radiations replicated in rivers

Parallel adaptive radiations have arisen following the colonization of islands by lizards and lakes by fishes. In these classic examples, adaptive radiation is a response to the ecological opportunities afforded by the colonization of novel ecosystems and similar adaptive landscapes that favor 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 assemblages of pike cichlids (Crenicichla) 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.平行适应性辐射（Parallel adaptive radiations）多形成于蜥蜴拓殖岛屿、鱼类定居湖泊之后。在这些经典案例中，适应性辐射是对开拓新型生态系统所赋予的生态机遇，以及相似适应性景观的响应——尽管各支系的演化历史彼此独立，此类景观仍会催生高度相似的生态形态（ecomorph）类群。本研究证实，慈鲷鱼类（cichlid fishes）的平行适应性辐射也出现于南美洲的河流流域中。矛丽鱼属（Crenicichla）经物种形成过程组建的群落，在乌拉圭河与巴拉那河两条流域中独立分化出相似的新型生态形态类群，涵盖缝隙摄食者、周丛生物刮食者以及软体动物捕食者。伴随每条河流的拓殖事件，以及生态形态演化后形态空间（morphospace）的后续扩张，均出现了表型演化的爆发式事件。这些河流支系表明，即便在河流这类易变的生态系统中，经典教科书中岛屿与淡水湖泊类群的平行适应性辐射所标志性的特征，同样是可行的演化结果。