Studies on modifications on the internal cranial morphology in the evolution of anthropoid orbits

利用计算机断层扫描(CT)对现存的和化石的类人型灵长类动物的鼻窦解剖变异进行了广泛的研究，并对系统发育分析具有潜在的实用价值。我们使用这种方法对京都大学灵长类研究所和瑞士苏黎世大学的18个现存链鼻目动物的解剖学进行了评估。上颌窦在所有属中均有形成。鼻状突起还有一个通向鼻腔的假性开口。在Propithecus，如大猩猩和Pithecia所见，下鼻道在这个鼻窦前面的区域向外扩张，上颌窦被分成三个不同的腔室，分别有通向中鼻道的开口。在Eulemur，在这个窦的后面区域形成了一个额外的窦状腔。尽管体积不同，但所有属的蝶骨气化都有一个通往筛区的开口。…的独特模式额区的气化度在Eulemur、Daubentonia、Indri、Propithecus和Avahi较多。Avahi的额窦与上颌窦相连。在许多其他属中，在环额筛区形成一个从筛区扩展出来的小腔，这一特征可能与额窦同源。与其他科相比，眼镜蛇科的副鼻窦形态更为多样。目前的研究证实了这样的观点，即东半球猴子缺乏副鼻窦在灵长目动物中是相当独特的。上颌窦在结构上向外扩展到眶底部和磨牙牙槽之间的间隙，并伴有面部下部向眶-颅区的下部旋转。这样的修改有助于轨道的前移。因此，上颌窦的侧向扩张程度可以用来检验化石标本的眼眶人性化程度。较少

Variations in the paranasal sinus anatomy of extant and fossil anthropoid primates have been extensively examined using computed tomography (CT), and have potential utility for phylogenetic analyses. We used this approach to evaluate the anatomy in 18 genera of extant strepsirrhines housed in the Primate Research Institute, Kyoto University and the University of Zurich, Switzerland. The maxillary sinus is formed in all the genera. The lorisiforms have an additional pseudo-ostium opening to the nasal cavity. In Propithecus, the inferior meatus expands laterally in the region anterior to this sinus, as seen in Gorilla and Pithecia, and the maxillary sinus is segmented into three distinct chambers which have openings to the middle meatus, respectively. In Eulemur, an additional sinus-like cavity is formed in the region posterior to this sinus. Sphenoidal pneumatization with an opening to the ethmoidal region is found in all the genera, despite of differences in volume. Distinct patterns o … More f pneumatization of the frontal region are found in Eulemur, Daubentonia, Indri, Propithecus, and Avahi. The frontal sinus in Avahi communicates with the maxillary sinus. In many of the other genera, a small cavity expanding from the ethmoidal region is formed in the circumfrontal-ethmoidal region, and this feature is probably homologous to the frontal sinus. The paranasal sinuses are more variable in form in the Indridae than in the other families. The present study confirms the view that the lack of paranasal sinuses in the Old World monkeys is quite unique among the order Primates. The maxillary sinus expanding laterally into the space between the orbital floor and molar alveolar is structurally accompanied with the inferior rotation of the lower facial part against the orbital-cranial region. Such a modification contributes to the frontation of the orbits. Thus, the degree in lateral expansion of the maxillary sinus could be available for examining the orbital anthropoidization in fossil specimens. Less