Nargolwalla M C, Begun D R, Dean M C, Reid D J, Kordos L
Department of Anthropology, University of Toronto, Toronto, ON, M5S 3G3, Canada.
J Hum Evol. 2005 Jul;49(1):99-121. doi: 10.1016/j.jhevol.2005.03.008.
The sample of Anapithecus from Rudabánya, Hungary, is remarkable in preserving a large number of immature individuals. We used perikymata counts, measurements of root length and cuspal enamel thickness, and observations of the sequence of tooth germs that cross match specific developmental stages in Anapithecus to construct the first composite picture and time scale for dental development in a pliopithecoid (Catarrhini, Primates). We conclude that the age of eruption of M1 in Anapithecus was similar to various macaque species (approximately 1.45 months), but that M2 and M3 emergence were close to 2.2 and 3.2 years, respectively (both earlier than expected for similarly sized cercopithecoids). There may have been little difference in individual tooth formation times between cercopithecoids and Anapithecus, but the degree of molar overlap during M1, M2, and M3 crown development, which is extreme in Anapithecus, is fundamentally different. Overall dental development in Anapithecus was very rapid. Old World monkeys appear derived in lacking significant molar overlap, and hominoids may be derived in having longer tooth formation times, both resulting in longer overall dental development times. This is consistent with the general conclusion that the Pliopithecoidea is an outgroup to the Cercopithecoidea and the Hominoidea. On the other hand, rapid dental formation in Anapithecus may be an apomorphy indicative of an unusually rapid life history or unique pressures related to diet and maturation. Folivory and/or predation pressure may be responsible for generating selection to more rapidly erupt permanent teeth and possibly attain adult body masses in Anapithecus. Whatever the case, Anapithecus, with an M3 emergence of approximately 3.2 years, is dramatically faster than any extant catarrhine of similar body mass. This represents yet another unusual attribute of this poorly known fossil catarrhine.
来自匈牙利鲁达巴尼亚的阿纳皮猿样本在保存大量未成熟个体方面非常显著。我们利用釉质生长线计数、牙根长度和牙尖釉质厚度测量，以及对牙胚序列的观察，这些牙胚序列与阿纳皮猿的特定发育阶段相互匹配，从而构建了第一个关于阔鼻猴类（狭鼻小目，灵长目）牙齿发育的综合图景和时间尺度。我们得出结论，阿纳皮猿中M1的萌出年龄与各种猕猴物种相似（约1.45个月），但M2和M3的萌出分别接近2.2岁和3.2岁（均早于体型相似的猕猴科动物的预期）。猕猴科动物和阿纳皮猿之间单个牙齿形成时间可能差异不大，但在M1、M2和M3牙冠发育期间磨牙重叠程度在阿纳皮猿中极为明显，这在本质上是不同的。阿纳皮猿的整体牙齿发育非常迅速。旧世界猴类似乎因缺乏显著的磨牙重叠而有所不同，类人猿可能因牙齿形成时间较长而有所不同，这两者都导致整体牙齿发育时间更长。这与一般结论一致，即阔鼻猴类是猕猴科动物和类人猿的外类群。另一方面，阿纳皮猿快速的牙齿形成可能是一种衍征，表明其具有异常快速的生活史或与饮食和成熟相关的独特压力。食叶和/或捕食压力可能导致选择在阿纳皮猿中更快速地萌出恒牙并可能达到成年体重。无论如何，M3萌出约为3.2岁的阿纳皮猿比任何现存的体型相似的狭鼻小目动物都要快得多。这代表了这种鲜为人知的化石狭鼻小目动物的又一个不寻常特征。
