Naya Daniel E, Veloso Claudio, Muñoz José L P, Bozinovic Francisco
Center for Advanced Studies in Ecology and Biodiversity, and Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, CP 6513677, Chile.
Comp Biochem Physiol A Mol Integr Physiol. 2007 Feb;146(2):189-93. doi: 10.1016/j.cbpa.2006.10.014. Epub 2006 Oct 14.
Lizard tail autotomy is considered an efficient anti-predator strategy that allows animals to escape from a predator attack. However, since the tail also is involved in many alternative functions, tailless animals must cope with several costs following autotomy. Here we explicitly evaluate the consequences of tail autotomy for two costs that have been virtually unexplored: 1. we test whether the anatomical change that occurs after tail loss causes a reduction in the role of the tail as a distraction mechanism to predators; 2. we analyzed whether tail synthesis comprises an energetically costly process in itself, by directly comparing the cost of maintenance before and after autotomy. We found that original tails displace further and at greater velocity than regenerated tails, indicating that the anti-predation responses of a lizard probably changes according to whether its tail is original or regenerated. With regard to the energetic cost of tail synthesis, we observed a significant increase in the standard metabolic rate, which rose 36% in relation to the value recorded prior to tail loss. This result suggests that the energetic cost of tail synthesis itself could be enough to affect lizard fitness.
蜥蜴断尾被认为是一种有效的反捕食策略，能让动物逃脱捕食者的攻击。然而，由于尾巴还参与许多其他功能，断尾后的无尾动物必须应对断尾带来的多种代价。在此，我们明确评估断尾对两种几乎未被探索的代价的影响：1. 我们测试尾巴丢失后发生的解剖学变化是否会导致尾巴作为对捕食者的干扰机制的作用减弱；2. 我们通过直接比较断尾前后的维持成本，分析尾巴再生本身是否是一个能量消耗巨大的过程。我们发现，原始尾巴比再生尾巴移动得更远、速度更快，这表明蜥蜴的反捕食反应可能会根据其尾巴是原始的还是再生的而发生变化。关于尾巴再生的能量成本，我们观察到标准代谢率显著增加，相对于断尾前记录的值上升了36%。这一结果表明，尾巴再生本身的能量成本可能足以影响蜥蜴的适应性。
