Department of Rehabilitation Sciences, Florida Gulf Coast University, Fort Myers, Florida, USA.
Department of Biological Sciences, Florida Gulf Coast University, Fort Myers, Florida, USA.
Am J Primatol. 2021 May;83(5):e23246. doi: 10.1002/ajp.23246. Epub 2021 Feb 27.
Multiple behavioral and biomechanical analyses have demonstrated that capuchin monkeys (Cebus and Sapajus) are specialized for breaking down hard-object foods as compared to other cebid monkeys. In addition to a complex suite of craniodental adaptations, it has specifically been demonstrated that capuchins possess highly complex dental enamel, with extensive Hunter-Schreger banding and other decussation, that likely serve as an adaptation to resist crack propagation during hard-object feeding. Furthermore, it has been demonstrated that robust capuchins (Sapajus spp., formerly Cebus apella) demonstrate further adaptation for hard-object feeding than other capuchins, routinely breaking down extremely mechanically challenging foods. However, there has been no comparison of dental enamel complexity in robust versus gracile capuchins, to assess whether the dental enamel in Sapajus follows this same pattern of further specialization. Therefore, this study compares dental enamel complexity in images of dental thin sections from a sample of robust versus gracile capuchins using image compression ratio (ICR) analysis. ICR is a variable that correlates with enamel complexity, such that higher ICR values are indicative of increased complexity in the form of enamel decussation. We found no significant difference between robust and gracile capuchins when assessing all teeth in our sample together, however, we did find that robust capuchins have significantly higher ICR values than gracile capuchins for canine teeth, specifically. Our results support prior studies suggesting that robust capuchins are specialized to generate increased masticatory loads with their anterior dentition, specifically, as compared to gracile species.
多项行为和生物力学分析表明，与其他卷尾猴相比，卷尾猴（僧帽猴属和蛛猴属）专门用于破解硬质食物。除了一系列复杂的颅面适应外，具体证明了卷尾猴具有非常复杂的牙釉质，具有广泛的 Hunter-Schreger 带和其他交错，这可能是一种适应，以抵抗在硬物体喂养过程中的裂纹扩展。此外，已经证明，强壮的卷尾猴（Sapajus spp.，以前称为 Cebus apella）比其他卷尾猴具有进一步适应硬物体喂养的能力，经常破解极其具有挑战性的机械食物。然而，尚未比较强壮和纤细的卷尾猴的牙釉质复杂性，以评估 Sapajus 的牙釉质是否遵循相同的进一步专业化模式。因此，本研究使用图像压缩比（ICR）分析比较了来自强壮和纤细卷尾猴样本的牙薄片图像中的牙釉质复杂性。ICR 是与牙釉质复杂性相关的变量，较高的 ICR 值表明牙釉质交错的复杂性增加。当我们一起评估我们样本中的所有牙齿时，我们没有发现强壮和纤细的卷尾猴之间有显着差异，但我们确实发现强壮的卷尾猴的犬齿的 ICR 值明显高于纤细的卷尾猴。我们的研究结果支持了先前的研究，表明强壮的卷尾猴专门通过其前齿系产生增加的咀嚼负荷，特别是与纤细物种相比。
