Department of Evolution and Ecology, University of California, Davis, California 95616, USA.
Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095, USA.
Nat Commun. 2014 Nov 17;5:5505. doi: 10.1038/ncomms6505.
The demand that anatomical structures work together to perform biological functions is thought to impose strong limits on morphological evolution. Breakthroughs in diversification can occur, however, when functional integration among structures is relaxed. Although such transitions are expected to generate variation in morphological diversification across the tree of life, empirical tests of this hypothesis are rare. Here we show that transitions between suction-based and biting modes of prey capture, which require different degrees of coordination among skull components, are associated with shifts in the pattern of skull diversification in eels (Anguilliformes). Biting eels have experienced greater independence of the jaws, hyoid and operculum during evolution and exhibit more varied morphologies than closely related suction feeders, and this pattern reflects the weakened functional integration among skull components required for biting. Our results suggest that behavioural transitions can change the evolutionary potential of the vertebrate skeleton by altering functional relationships among structures.
人们认为，解剖结构需要协同工作以执行生物功能，这对形态进化施加了很强的限制。然而，当结构之间的功能整合得到放松时，多样化的突破就有可能发生。尽管预计这种转变会在生命之树上产生形态多样化的变化，但对这一假设的经验测试却很少。在这里，我们表明，基于吸力的猎物捕捉模式和基于咬伤的猎物捕捉模式之间的转变，需要颅骨成分之间不同程度的协调，这与鳗鱼（鳗鲡目）颅骨多样化模式的转变有关。在进化过程中，咬伤鳗鱼的下颚、舌骨和鳃盖的独立性更大，并且表现出比亲缘关系密切的吸食者更多样的形态，这种模式反映了咬伤所需的颅骨成分之间功能整合的减弱。我们的结果表明，行为转变可以通过改变结构之间的功能关系来改变脊椎动物骨骼的进化潜力。
