Does large body size relax constraints on bite-force generation in lizards of the genus Uromastyx?
Does large body size relax constraints on bite-force generation in lizards of the genus Uromastyx?
复制标题
大体型是否会放松对 Urosastyx 属蜥蜴咬合力产生的限制？
DOI：
10.1111/jzo.12089
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发表时间：
2014
影响因子：
2
通讯作者：
J. J. Wessels
中科院分区：
文献类型：
--
作者：
A. Herrel;A. Castilla;M. Al‐Sulaiti;J. J. Wessels
大型体型的进化通常被认为是蜥蜴食草性进化的关键特征。尽管许多杂食性蜥蜴看起来没有特异功能，但它们通常表现出很高的咬合力，使它们能够减少坚韧和纤维状的植物物质。相比之下，真正的食草动物通常表现出一系列的形态和生理特化，使它们能够有效地处理和同化植物材料。此外，许多专门的食草动物体型很大，因此可能会放松对咬合力产生的限制，因为咬合力随着体重的增加而增加。在这项研究中，我们测试大型食草性蜥蜴是否与中等大小的同类相比，其身体大小的咬合力相对较小。在我们的样本中，两个物种之间或性别之间没有观察到咬合力或头部尺寸的差异。此外，咬合力与颌长呈正异速生长，这表明较大的动物具有不成比例的大咬合力。这表明，即使在最大的物种中，咬合力的产生仍然受到很强的限制，这可能是由于饮食的机械特性对颌骨系统的要求。
The evolution of large body size has often been considered a key trait allowing the evolution of herbivory in lizards. Although many omnivorous lizards appear unspecialized, they typically show high bite forces, allowing them to reduce tough and fibrous plant matter. In contrast, true herbivores often show a suite of morphological and physiological specializations, allowing them to efficiently process and assimilate plant material. Moreover, many specialized herbivores have a large body size, thus likely relaxing constraints on bite-force generation given that bite force increases with increasing body mass. In this study, we test whether large herbivorous lizards of the genus Uromastyx have relatively lower bite forces for their body size compared with a medium-sized congener. No differences in bite force or head dimensions were observed between the two species or between both sexes in our sample. Moreover, bite force scaled with positive allometry relative to jaw length, suggesting that larger animals have disproportionately large bite forces. This suggests that even in the largest species, constraints on bite-force generation are still strong, possibly due to the demands imposed on the jaw system by the mechanical properties of the diet.