Department of Anatomy and Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25704, USA.
Am J Phys Anthropol. 2010 Jan;141(1):131-41. doi: 10.1002/ajpa.21137.
The infraorbital foramen (IOF) transmits the infraorbital nerve (ION) to specialized sensory cells (mechanoreceptors) in the maxillary region. The size of the IOF has been used in numerous paleoecological interpretations of the fossil record. However, these interpretations have been applied without an explicit analysis of the relationship between ecological variables and the IOF. ION and IOF cross-sectional area show a strong positive correlation. As a result, IOF area can be a proxy for ION area, and it is hypothesized that IOF area may be a good measure for maxillary somatosensory acuity. Differences in diet, substrate preference, and/or activity pattern have been shown to correlate with differences in maxillary somatosensory acuity among mammals. This study examines how IOF area covaries with different ecological variables. IOF area was measured for 89 primate species. Ecological profiles were also created for each species and used to evaluate interspecific variation in relative IOF area within each ecological category. The results show a significant relationship between relative IOF area and diet, but not substrate preference or activity pattern. Frugivores have significantly larger relative IOFs than either folivores or insectivores, but the relative IOFs of folivores and insectivores do not differ significantly from one another. These results partially support the hypothesis that maxillary mechanoreception is a critical sensory cue for primates within a feeding context. Results for this study suggest the IOF can be used as an informative character in some paleoecological interpretations of the primate fossil record.
眶下孔（IOF）传送眶下神经（ION）到上颌区域的专门感觉细胞（机械感受器）。眶下孔的大小已被用于大量古生态学对化石记录的解释。然而，这些解释在没有明确分析生态变量与 IOF 之间的关系的情况下就被应用了。ION 和 IOF 的横截面积显示出很强的正相关。因此，IOF 区域可以作为 ION 区域的代理，并且假设 IOF 区域可能是上颌体感觉敏锐度的一个很好的衡量标准。饮食、基质偏好和/或活动模式的差异已被证明与哺乳动物上颌体感觉敏锐度的差异相关。本研究探讨了 IOF 区域如何与不同的生态变量相关。测量了 89 种灵长类物种的 IOF 区域。还为每个物种创建了生态档案，并用于评估每个生态类别内相对 IOF 区域的种间变化。结果表明，相对 IOF 区域与饮食之间存在显著关系，但与基质偏好或活动模式无关。果食动物的相对 IOF 明显大于食叶动物或食虫动物，但食叶动物和食虫动物的相对 IOF 没有明显差异。这些结果部分支持了这样的假设，即上颌体机械感觉对于在进食环境中的灵长类动物是一个关键的感觉线索。本研究的结果表明，IOF 可以作为灵长类化石记录的某些古生态学解释中的一个有用特征。
