Van Wassenbergh Sam, Bonte Christoffel, Michel Krijn B
Department of Biology University of Antwerp Antwerp Belgium.
Département d'Ecologie et de Gestion de la Biodiversité Muséum National D'Histoire Naturelle UMR 7179 CNRS Paris Cedex 05 France.
Ecol Evol. 2017 Apr 21;7(11):3856-3860. doi: 10.1002/ece3.2694. eCollection 2017 Jun.
Due to morphological resemblance, polypterid fishes are used as extant analogues of Late Devonian lobe-finned sarcopterygians to identify the features that allowed the evolution of a terrestrial lifestyle in early tetrapods. Previous studies using polypterids showed how terrestrial locomotion capacity can develop, and how air ventilation for breathing was possible in extinct tetrapodomorphs. Interestingly, one polypterid species, the reedfish , has been noted being capable of capturing prey on land. We now identified the mechanism of terrestrial prey-capture in reedfish. We showed that this species uses a lifted trunk and downward inclined head to capture ground-based prey, remarkably similar to the mechanism described earlier for eel-catfish. Reedfish similarly use the ground support and flexibility of their elongated body to realize the trunk elevation and dorsoventral flexion of the anterior trunk region, without a role for the pectoral fins. However, curving of the body to lift the trunk may not have been an option for the Devonian tetrapodomorphs as they are significantly less elongated than reedfish and eel-catfish. This would imply that, in contrast to the eel-like extant species, evolution of the capacity to capture prey on land in early tetrapods may be linked to the evolution of the pectoral system to lift the anterior part of the body.
由于形态相似，多鳍鱼被用作晚泥盆世肉鳍鱼类的现存类似物，以确定早期四足动物陆地生活方式进化所需的特征。此前对多鳍鱼的研究展示了陆地运动能力是如何发展的，以及已灭绝的四足形动物如何实现呼吸所需的空气流通。有趣的是，有一种多鳍鱼，即芦苇鱼，被发现能够在陆地上捕食猎物。我们现在确定了芦苇鱼在陆地上捕食猎物的机制。我们发现，这种鱼利用抬起的躯干和向下倾斜的头部来捕捉地面上的猎物，这与之前描述的鳗鲶的机制非常相似。芦苇鱼同样利用地面支撑和其细长身体的灵活性来实现躯干抬高和前躯区域的背腹弯曲，胸鳍在此过程中不起作用。然而，对于泥盆纪的四足形动物来说，通过弯曲身体来抬起躯干可能不是一个可行的办法，因为它们的身体不像芦苇鱼和鳗鲶那样细长。这意味着，与现存的鳗类物种不同，早期四足动物在陆地上捕食猎物的能力的进化可能与胸鳍系统进化以抬起身体前部有关。
