Department of Biological Sciences, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, Canada, T2N 1N4.
Integr Comp Biol. 2002 Dec;42(6):1154-63. doi: 10.1093/icb/42.6.1154.
Climbing assisted by adhesive subdigital pads in gekkotan lizards has been the subject of intrigue and study for centuries. Many hypotheses have been advanced to explain the mechanism of adhesion, and recently this phenomenon has been investigated at the level of individual setae. The ability to isolate, manipulate and record adhesive forces from individual setae has provided new insights, not only into the mechanism of attachment, but also into the physical orientation of these structures necessary to establish attachment, maximize adhesive force, and effect subsequent release. This, in turn, has enabled a reassessment of the overall morphology and mode of operation of the adhesive system. Digital hyperextension has often been noted as a behavioral characteristic associated with the deployment of the gekkotan adhesive system-this is now understandable in the context of setal attachment and release kinematics, and in the context of the evolution of this pattern of digital movement from the primitive pattern of saurian digital kinematics. The perpendicular and parallel preloads associated with setal attachment are now reconcilable with other morphological aspects of the gekkotan adhesive system-the lateral digital tendon complex and the vascular sinus network, respectively. Future investigations of the integrated adhesive system will help to further elucidate the interdependence of its structural and functional components.
壁虎类蜥蜴的附著性趾垫辅助攀爬，数百年来一直是人们好奇和研究的主题。人们提出了许多假说来解释附著的机制，最近，这种现象已经在单个刚毛的水平上进行了研究。能够隔离、操纵和记录单个刚毛的粘附力，不仅为附著的机制提供了新的见解，也为这些结构的物理取向提供了新的见解，这些结构对于建立附著、最大化粘附力和实现随后的释放是必要的。这反过来又使人们能够重新评估整个粘附系统的整体形态和操作模式。数字超伸展通常被认为是与壁虎类粘附系统部署相关的行为特征——现在，从原始的爬行动物数字运动模式来看，从刚毛的附着和释放运动学来看，以及从这种数字运动模式的演变来看，这是可以理解的。与刚毛附着相关的垂直和平行预加载现在可以与壁虎类粘附系统的其他形态方面协调一致——分别是横向数字肌腱复合体和血管窦网络。对集成粘附系统的未来研究将有助于进一步阐明其结构和功能组件的相互依存关系。
