Monteiro Leandro R, Bonato Vinícius, Dos Reis Sérgio F
Laboratório de Ciências Ambientais-CBB, Universidade Estadual do Norte Fluminense, Av. Alberto Lamego, 2000, 28013-600 Campos dos Goytacazes, RJ, Brazil.
Evol Dev. 2005 Sep-Oct;7(5):429-39. doi: 10.1111/j.1525-142X.2005.05047.x.
The rodent mandible has become a paradigm for studies on the development and evolution of complex morphological structures. We use a combination of geometric and multivariate morphometric methods in order to assess the correspondence between integration patterns and a priori biological models in the context of evolutionary shape divergence in the mandible of rodents of the family Echimyidae. The correlation of shape distances among operational taxonomic units (individuals, species, genera) in separate morphogenetic components allowed the construction of integration matrices among mandible components for data sets corresponding to varying levels of genetic divergence (intergeneric, interspecific, and intrapopulational). The integration matrices were associated with a priori biological (developmental, genetical, modular) models, and the maximum integration axes (singular warps) were compared with realized axes of maximum interspecific variation (relative warps). The integration pattern and intensity were not stable in data sets with different levels of genetic divergence, and the varying functional demands during the ecological radiation in the family were probably responsible for the differences in observed integration patterns. Developmental and genetic models were significantly associated with the interspecific integration patterns observed, suggesting a role for neutral evolution during the evolutionary divergence of mandible shape. However, directional and stabilizing selection were not discarded as processes responsible for the generation of interspecific integration. The choreography of the morphogenetic components in the mandible is highly flexible and the integrated groups of components can be reorganized depending on functional demands during evolutionary shape changes.
啮齿动物的下颌骨已成为研究复杂形态结构发育与进化的范例。我们运用几何和多变量形态测量方法相结合的方式，以评估在棘鼠科啮齿动物下颌骨进化形态差异的背景下，整合模式与先验生物学模型之间的对应关系。通过对不同形态发生成分中操作分类单元（个体、物种、属）间形状距离的相关性分析，得以构建对应不同遗传分化水平（属间、种间和种群内）数据集的下颌骨各成分间的整合矩阵。这些整合矩阵与先验生物学（发育、遗传、模块）模型相关联，并将最大整合轴（奇异 warp）与最大种间变异的实际轴（相对 warp）进行比较。在不同遗传分化水平的数据集中，整合模式和强度并不稳定，该科生态辐射过程中功能需求的变化可能是导致观察到的整合模式差异的原因。发育和遗传模型与所观察到的种间整合模式显著相关，这表明在下颌骨形态进化分歧过程中，中性进化发挥了作用。然而，定向选择和稳定选择作为导致种间整合产生的过程也不能被排除。下颌骨形态发生成分的编排具有高度灵活性，在进化形态变化过程中，整合的成分组可根据功能需求进行重组。
