Department of Anthropology, New York University, NY 10003, USA.
Am J Phys Anthropol. 2013 Jan;150(1):38-47. doi: 10.1002/ajpa.22209.
Dental development and skeletal growth are central aspects used by anthropologists when investigating the ontogeny of a population or species. The interrelatedness of the two phenomena is often assumed to be high, but the nature of their relationship is obscured by the fact that they are both highly dependent upon chronological age. The exact relationship between the tempo of dental development and skeletal growth is unclear even in modern humans, which limits the ability to extrapolate to archaeological or fossil forms. It is clear that the influence of chronological age on these two aspects of ontogeny must be accounted for before examining their relationship to one another. This study tests whether dental development and skeletal growth are conditionally independent given age using known-age modern human skeletal samples and proportional odds logistic regression. The results suggest that dental development and skeletal growth are moderately correlated and thus not conditionally independent given age. That is, individuals that are dentally advanced relative to their peers also tend to be skeletally advanced. However, this relationship is moderate at best, so dental development does not appear to be a highly reliable proxy for skeletal growth, or vice versa, in modern humans. These findings have implications for the reconstruction of ontogeny and life history of fossil hominin taxa, since the pace of dental development is often used as a life history proxy. Implications of this study suggest that the proposed accelerated dental development in Pleistocene hominins was not necessarily accompanied by faster skeletal growth.
牙齿发育和骨骼生长是人类学家在研究一个种群或物种的个体发育时使用的两个核心方面。这两种现象之间的相关性通常被认为是很高的，但由于它们都高度依赖于年龄，因此它们之间关系的本质是模糊的。即使在现代人类中，牙齿发育和骨骼生长之间的精确关系也不清楚，这限制了将其推断到考古或化石形态的能力。显然，在研究它们彼此之间的关系之前，必须考虑年龄对这两个个体发育方面的影响。本研究使用已知年龄的现代人类骨骼样本和比例优势逻辑回归，测试了在考虑年龄的情况下，牙齿发育和骨骼生长是否具有条件独立性。结果表明，在考虑年龄的情况下，牙齿发育和骨骼生长具有中度相关性，因此不具有条件独立性。也就是说，相对于同龄人牙齿发育更快的个体，骨骼发育也往往更快。然而，这种关系最多只是中度的，因此在现代人类中，牙齿发育似乎不是骨骼生长的高度可靠指标，反之亦然。这些发现对重建化石人科动物的个体发育和生活史具有重要意义，因为牙齿发育的速度通常被用作生活史的指标。本研究的意义表明，在更新世人类中提出的加速牙齿发育不一定伴随着更快的骨骼生长。
