Taylor Andrea B, Terhune Claire E, Toler Maxx, Holmes Megan, Ross Callum F, Vinyard Christopher J
Department of Basic Science, College of Osteopathic Medicine, Touro University, Vallejo, California.
Department of Anthropology, University of Arkansas, Fayetteville, Arkansas.
Anat Rec (Hoboken). 2018 Feb;301(2):325-342. doi: 10.1002/ar.23718.
Numerous studies have sought to link craniofacial morphology with behavioral ecology in primates. Extant hard-object feeders have been of particular interest because of their potential to inform our understanding about the diets of early fossil hominins. Sooty mangabeys (Cercocebus atys) are hard-object feeders that frequently generate what have been described as audibly powerful bites at wide jaw gapes to process materially stiff and hard seeds. We address the hypothesis that sooty mangabeys have features of the masticatory apparatus that facilitate this feeding behavior by comparing fiber architecture and leverage of the masseter and temporalis muscles between sooty mangabeys and three papionin primates that do not specialize on hard objects. Contrary to predictions, sooty mangabeys do not have relatively larger muscle physiologic cross-sectional areas or weights compared to other papionins, nor do they consistently display improved leverage. In this regard, sooty mangabeys differ in their morphology from other hard-object feeders such as tufted capuchins. However, males of all four papionin species converge on a shared pattern of relatively longer anterior superficial masseter fibers compared with female conspecifics, suggesting that males are likely prioritizing muscle stretch to improve gape performance as part of a behavioral repertoire that includes agonistic social interactions and intense male-male competition. These findings strengthen support for the hypothesis that gape display behaviors can exert a strong selective influence throughout the musculoskeletal masticatory apparatus. Results also raise questions about the morphological suitability of extant cercopithecines as models for interpreting feeding behavior and diet in fossil hominins with limited jaw gape capacity. Anat Rec, 301:325-342, 2018. © 2018 Wiley Periodicals, Inc.
众多研究试图将灵长类动物的颅面形态与行为生态学联系起来。现存的硬食性动物尤其受到关注，因为它们有助于我们了解早期化石人类的饮食。黑冠猕猴（Cercocebus atys）是硬食性动物，它们在张大嘴巴时经常用力咬，发出很大声响，以处理质地坚硬的种子。我们通过比较黑冠猕猴与三种非硬食性狒狒灵长类动物的咬肌和颞肌的纤维结构及杠杆作用，来验证黑冠猕猴咀嚼器官具有便于这种进食行为的特征这一假设。与预测相反，与其他狒狒相比，黑冠猕猴并没有相对更大的肌肉生理横截面积或重量，也没有始终表现出更好的杠杆作用。在这方面，黑冠猕猴在形态上与其他硬食性动物如簇绒卷尾猴不同。然而，所有四种狒狒灵长类动物的雄性与雌性相比，都有相对较长的咬肌前表层纤维的共同模式，这表明雄性可能优先考虑肌肉伸展以改善张口能力，这是包括攻击性社会互动和激烈的雄性间竞争在内的行为模式的一部分。这些发现进一步支持了张口展示行为会对整个咀嚼肌肉骨骼系统产生强大选择影响这一假设。研究结果也引发了一些问题，即现存猕猴作为解释有限张口能力的化石人类进食行为和饮食的模型，其形态学上的适用性如何。《解剖学记录》，301:325 - 342，2018年。© 2018威利期刊公司。
