Barbeito-Andrés Jimena, Ventrice Fernando, Anzelmo Marisol, Pucciarelli Héctor M, Sardi Marina L
División Antropología, Museo de La Plata, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900, La Plata, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
Laboratorio de Neuroimágenes, Departamento de Imágenes, Instituto de Investigaciones Neurológicas Raúl Carrea, FLENI, Montañeses 2325, 1428 Ciudad Autónoma de Buenos Aires (Buenos Aires), Argentina.
Ann Anat. 2015 Jan;197:59-66. doi: 10.1016/j.aanat.2014.10.002. Epub 2014 Oct 18.
In the present study, we analyzed postnatal ontogenetic integration among morphological traits of the human neurocranium. Particularly, the covariation between the vault and the base during postnatal life was assessed. Since the association between these regions may depend on the generalized change produced by allometry, we tested its effect on their covariation. On a sample of adults and subadults ranging from 0 to 31 years, 3D coordinates of neurocranial landmarks and semilandmarks were digitized and geometric morphometric technics were applied. Main aspects of shape variation were examined using Principal Components analysis. Covariation between the vault and the base was examined by Partial Least Squares analysis. According to our results, the vault and the base covary strongly during postnatal ontogeny and their relation depends largely on allometry. Two size variables were studied: centroid size, which was obtained from the recorded morphometric points, and endocranial volume, taken as an estimation of brain size. Although growing brain was found to be a developmental process that contributes to covariation among neurocranial traits, there would be other factors that exert their influence during ontogeny. These results lead to reconsider cranial morphological evolution taking into account the developmental constraints given by ontogenetic patterns of integration and reinforcing the idea that in human evolution a suite of relevant characters may be fuelled by few developmental processes.
在本研究中，我们分析了人类脑颅形态特征的出生后个体发育整合情况。具体而言，评估了出生后颅顶和颅底之间的协变情况。由于这些区域之间的关联可能取决于异速生长产生的普遍变化，我们测试了其对它们协变的影响。在一个年龄范围从0到31岁的成年人和亚成年人样本上，对脑颅地标和半地标进行了三维坐标数字化，并应用了几何形态测量技术。使用主成分分析检查了形状变化的主要方面。通过偏最小二乘法分析检查了颅顶和颅底之间的协变情况。根据我们的结果，颅顶和颅底在出生后个体发育过程中强烈协变，它们之间的关系在很大程度上取决于异速生长。研究了两个大小变量：从记录的形态测量点获得的质心大小，以及作为脑大小估计值的颅内容积。虽然不断生长的大脑被认为是一个导致脑颅特征协变的发育过程，但在个体发育过程中还会有其他因素发挥作用。这些结果促使我们在考虑个体发育整合模式所赋予的发育限制的情况下重新思考颅骨形态进化，并强化了这样一种观点，即在人类进化中，一系列相关特征可能由少数发育过程驱动。
