Ackermann Rebecca Rogers
Department of Archaeology, Faculty of Science, University of Cape Town, Private Bag, Rondebosch 7701, South Africa.
J Hum Evol. 2005 Feb;48(2):175-97. doi: 10.1016/j.jhevol.2004.11.001.
By investigating similarity in cranial covariation patterns, it is possible to locate underlying functional and developmental causes for the patterning, and to make inferences about the evolutionary forces that have acted to produce the patterns. Furthermore, establishing where these covariation patterns may diverge in ontogeny can offer insight into when selection may have acted on development. Here, covariation patterns are compared among adult and non-adult members of the African ape/human clade, in order to address three questions. First, are integration patterns constant among adult African apes and humans? Second, are they are constant in non-adults--i.e. throughout ontogeny? Third, if they are not constant, when do they diverge? Measurements are obtained from 677 crania of adult and non-adult African apes and humans. In order to address the first two questions, correlation matrices and theoretical integration matrices are compared using matrix correlation methods. The third question is evaluated by comparing correlation and variance/covariance patterns, using matrix correlation and random skewers methods, respectively, between adjacent age categories within each species, and between equivalent age categories among the four species. Results show that the hominoids share a similar pattern of ontogenetic integration, suggesting that common developmental/functional integrative processes may play an important role in keeping covariance structure stable across this lineage. However, there are some important differences in the magnitude of integration and in phenotypic covariance structure among the species, which may provide some insight into how selection acted to differentiate humans from the great apes.
通过研究颅骨协变模式的相似性，有可能找出这种模式背后的功能和发育原因，并推断出导致这些模式产生的进化力量。此外，确定这些协变模式在个体发育过程中可能出现分歧的位置，有助于深入了解选择可能在何时作用于发育过程。在这里，我们比较了非洲猿/人类进化枝成年和未成年成员之间的协变模式，以解决三个问题。第一，成年非洲猿和人类的整合模式是否恒定？第二，它们在未成年个体中是否恒定——即在整个个体发育过程中？第三，如果它们不恒定，那么它们何时出现分歧？我们从677个成年和未成年非洲猿及人类的颅骨上获取了测量数据。为了解决前两个问题，我们使用矩阵相关方法比较了相关矩阵和理论整合矩阵。第三个问题则通过分别使用矩阵相关和随机串针法，比较每个物种相邻年龄组之间以及四个物种中同等年龄组之间的相关性和方差/协方差模式来评估。结果表明，类人猿具有相似的个体发育整合模式，这表明共同的发育/功能整合过程可能在保持该谱系协方差结构稳定方面发挥重要作用。然而，物种之间在整合程度和表型协方差结构上存在一些重要差异，这可能为了解选择如何使人类与大猩猩分化提供一些线索。
