Data from: Trophic divergence despite morphological convergence in a continental radiation of snakes

Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia – the oxyuranine elapids – exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. In contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others.生态与表型趋同是物种响应生态机遇时发生适应性辐射的潜在结果。然而，进化辐射过程中存在诸多因素会限制趋同演化，其中包括生物地理历史的区域间差异，以及支系特有的形态与功能约束。本研究证实，澳大利亚单支陆生蛇类支系——澳蛇亚科眼镜蛇类（oxyuranine elapids）——与系统发育多样性丰富且亲缘关系疏远的北美蛇类类群存在广泛的形态趋同现象。澳大利亚眼镜蛇类已演化出北美蛇类类群所具备的几乎全部表型类型。这类趋同现象大多涉及与觅食模式、运动方式及生境利用相关的典型形态的反复演化。与之形成鲜明对比的是，对蛇类食性的分析显示，这两大动物区系的摄食生态存在显著分化，这在一定程度上反映了澳大利亚与北美之间的生态异速生长区域差异。与北美蛇类动物区系广泛的表型趋同，加之摄食生态的显著分化，清晰地展现了独立的大陆辐射演化如何在部分生态轴向上发生趋同，却在其他轴向上产生巨大差异。