Harrison Shannon L, Sutton Gregory P, Herrel Anthony, Deeming D Charles
School of Natural Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln, UK.
Département Adaptations du Vivant, Bâtiment d'Anatomie Comparée, UMR 7179 C.N.R.S/M.N.H.N., Paris, France.
J Anat. 2025 Feb;246(2):299-315. doi: 10.1111/joa.14144. Epub 2024 Sep 24.
Jaw morphology and function determine the range of dietary items that an organism can consume. Bite force is a function of the force exerted by the jaw musculature and applied via the skeleton. Bite force has been studied in a wide range of taxa using various methods, including direct measurement, or calculation from skulls or jaw musculature. Data for parrots (Psittaciformes), considered to have strong bites, are rare. This study calculated bite force for a range of parrot species of differing sizes using a novel method that relied on forces calculated using the area of jaw muscles measured in situ and their masses. The values for bite force were also recorded in vivo using force transducers, allowing for a validation of the dissection-based models. The analysis investigated allometric relationships between measures of body size and calculated bite force. Additionally, the study examined whether a measure of a muscle scar could be a useful proxy to estimate bite force in parrots. Bite force was positively allometric relative to body and skull mass, with macaws having the strongest bite recorded to date for a bird. Calculated values for bite force were not statistically different from measured values. Muscle scars from the adductor muscle attachment on the mandible can be used to accurately predict bite force in parrots. These results have implications for how parrots process hard food items and how bite forces are estimated in other taxa using morphological characteristics of the jaw musculature.
颌骨形态和功能决定了生物体能够摄取的食物种类范围。咬合力是颌骨肌肉施加并通过骨骼传递的力的函数。人们已经使用各种方法对多种分类群的咬合力进行了研究，包括直接测量，或根据头骨或颌骨肌肉进行计算。关于鹦鹉（鹦形目）的咬合力数据很少，而鹦鹉被认为具有强大的咬合力。本研究使用一种新方法计算了一系列不同体型鹦鹉物种的咬合力，该方法依赖于根据原位测量的颌骨肌肉面积及其质量计算出的力。还使用力传感器在活体中记录咬合力值，以便对基于解剖的模型进行验证。该分析研究了体型测量值与计算出的咬合力之间的异速生长关系。此外，该研究还考察了肌肉疤痕的测量是否可以作为估计鹦鹉咬合力的有用指标。咬合力相对于身体和头骨质量呈正异速生长，金刚鹦鹉的咬合力是迄今为止记录到的鸟类中最强的。计算出的咬合力值与测量值在统计学上没有差异。下颌骨上内收肌附着处的肌肉疤痕可用于准确预测鹦鹉的咬合力。这些结果对于鹦鹉如何处理硬食物以及如何利用颌骨肌肉的形态特征估计其他分类群的咬合力具有启示意义。
