A diverse fossil record of Cervidae (Mammalia) has been documented in the South American Pleistocene, when these animals arrived during the Great American Biotic Interchange. Using computed tomography‐scanning techniques, it is possible to access the endocranial morphology of extinct species. Here, we studied the brain endocast of the extinct late Pleistocene cervid Antifer ensenadensis from southern Brazil, one of the largest forms that lived on this continent, using comparative morphology, geometric morphometrics, and encephalization quotients. The analyzed endocasts demonstrate that A. ensenadensis had a gyrencephalic brain, showing a prominent longitudinal sinus (=sagittal superior sinus), which is also observed in the large South American cervid Blastocerus dichotomus. The encephalization quotient is within the variation of extant cervids, suggesting maintenance of the pattern of encephalization from at least the late Pleistocene. Geometric morphometric analysis suggested a clear and linear allometric trend between brain endocast size and shape, and highlights A. ensenadensis as an extreme form within the analyzed cervids regarding brain morphology.

中文翻译：

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Antifer（哺乳动物：鹿科动物）的虚拟脑内模型，一种来自南美洲的已灭绝的大型鹿科动物

鹿科（哺乳动物）的多样化化石记录已记录在南美洲更新世，当时这些动物在美国大生物交换期间抵达。使用计算机断层扫描技术，可以访问已灭绝物种的颅内形态。在这里，我们使用比较形态学、几何形态测量学和脑化商研究了来自巴西南部已灭绝的晚更新世 cervid Antifer ensenadensis 的大脑内模型，这是生活在这个大陆上的最大的动物之一。分析的内模表明 A. ensenadensis 有一个回脑，显示出突出的纵向窦（=矢状上窦），这也在大型南美鹿类 Blastocerus dichotomus 中观察到。脑化商在现存鹿科动物的变异范围内，表明至少从晚更新世开始维持脑化模式。几何形态计量分析表明大脑内模大小和形状之间存在清晰的线性异速生长趋势，并强调 A. ensenadensis 作为分析的鹿科动物中关于大脑形态的极端形式。