Lee Sean M, Sutherland L J, Fruth Barbara, Murray Carson M, Lonsdorf Elizabeth V, Arbenz-Smith Keely, Augusto Rafael, Brogan Sean, Canington Stephanie L, Lee Kevin C, McGrath Kate, McFarlin Shannon C, Hohmann Gottfried
Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, District of Columbia, USA.
School of Communication and Information, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA.
Am J Phys Anthropol. 2021 Dec;176(4):684-691. doi: 10.1002/ajpa.24376. Epub 2021 Jul 26.
Existing data on bonobo and chimpanzee dental eruption timing are derived predominantly from captive individuals or deceased wild individuals. However, recent advances in noninvasive photographic monitoring of living, wild apes have enabled researchers to characterize dental eruption in relatively healthy individuals under naturalistic conditions. At present, such data are available for only one population of wild chimpanzees. We report data for an additional population of wild chimpanzees and the first dental eruption data for wild bonobos.
We collected photographs and video footage of teeth from the open mouths of wild bonobos and East African chimpanzees of known age from LuiKotale, Democratic Republic of the Congo, and Gombe National Park, Tanzania, respectively. We scored the presence and absence of deciduous teeth from photographs and video footage to characterize deciduous dental eruption timing in these two populations.
Deciduous dental eruption ages in our sample fall within the range of variation previously documented for captive chimpanzees, but eruption ages are later in wild than in captive contexts. We found substantial variation in deciduous canine eruption timing, particularly among bonobos. One bonobo had a deciduous canine present by 227 days old while another did not have a deciduous canine present at 477 days old.
Our data indicate that deciduous teeth erupt later in wild individuals than in captive individuals. We also found that deciduous dental eruption timing varies considerably between individuals within our study populations, a pattern that is consistent with previous studies. Future studies should consider sources of variation in deciduous canine eruption timing and relationships with other aspects of life history as additional data become available.
关于倭黑猩猩和黑猩猩牙齿萌出时间的现有数据主要来自圈养个体或死亡的野生个体。然而，对野生灵长类动物进行无创摄影监测的最新进展使研究人员能够在自然条件下对相对健康个体的牙齿萌出进行特征描述。目前，此类数据仅适用于一个野生黑猩猩种群。我们报告了另一个野生黑猩猩种群的数据以及野生倭黑猩猩的首批牙齿萌出数据。
我们分别从刚果民主共和国的卢伊科塔莱和坦桑尼亚的贡贝国家公园收集了已知年龄的野生倭黑猩猩和东非黑猩猩张开嘴时牙齿的照片和视频片段。我们根据照片和视频片段对乳牙的有无进行评分，以描述这两个种群乳牙萌出的时间。
我们样本中的乳牙萌出年龄落在先前记录的圈养黑猩猩的变异范围内，但野生环境中的萌出年龄比圈养环境中的要晚。我们发现乳牙犬齿萌出时间存在很大差异，尤其是在倭黑猩猩中。一只倭黑猩猩在227天大时就有了乳牙犬齿，而另一只在477天大时还没有乳牙犬齿。
我们的数据表明，野生个体的乳牙萌出比圈养个体晚。我们还发现，在我们的研究种群中，个体之间乳牙萌出时间差异很大，这一模式与先前的研究一致。随着更多数据的出现，未来的研究应考虑乳牙犬齿萌出时间变异的来源以及与生活史其他方面的关系。
