McGowan A J, Dyke G J
Department of Palaeontology, Natural History Museum, London, UK.
J Evol Biol. 2007 May;20(3):1230-6. doi: 10.1111/j.1420-9101.2006.01285.x.
Three vertebrate groups - birds, bats and pterosaurs - have evolved flapping flight over the past 200 million years. This innovation allowed each clade access to new ecological opportunities, but did the diversification of one of these groups inhibit the evolutionary radiation of any of the others? A related question is whether having the wing attached to the hindlimbs in bats and pterosaurs constrained their morphological diversity relative to birds. Fore- and hindlimb measurements from 894 specimens were used to construct a morphospace to assess morphological overlap and range, a possible indicator of competition, among the three clades. Neither birds nor bats entered pterosaur morphospace across the Cretaceous-Paleogene (Tertiary) extinction. Bats plot in a separate area from birds, and have a significantly smaller morphological range than either birds or pterosaurs. On the basis of these results, competitive exclusion among the three groups is not supported.
在过去两亿年里，有三类脊椎动物——鸟类、蝙蝠和翼龙——进化出了扑翼飞行。这一创新使得每个类群都获得了新的生态机遇，但其中一个类群的多样化是否抑制了其他类群的进化辐射呢？一个相关问题是，相对于鸟类，蝙蝠和翼龙的翅膀附着在后肢上是否限制了它们的形态多样性。研究人员利用来自894个标本的前肢和后肢测量数据构建了一个形态空间，以评估这三个类群之间形态上的重叠和范围，而形态重叠和范围可能是竞争的一个指标。在白垩纪-古近纪（第三纪）大灭绝期间，鸟类和蝙蝠都没有进入翼龙的形态空间。蝙蝠分布在与鸟类不同的区域，并且其形态范围明显小于鸟类或翼龙。基于这些结果，不支持这三个类群之间存在竞争排斥的观点。
