Department of Morphology, Piracicaba Dental School, State University of Campinas, 13414-900, Piracicaba, SP, Brazil.
Anat Rec (Hoboken). 2013 Apr;296(4):622-9. doi: 10.1002/ar.22667. Epub 2013 Feb 13.
The assembly of a phenotype into modules or developmental fields, which are semiautonomous units in development and function, seems to be one of the strategies to increase the capacity to produce phenotypic variation. In mammals the upper dentition is formed on two distinct developmental units, wherein incisors are formed on the primary palate, which is derived from the embryonic frontonasal process, and the other teeth (canine, premolar, and molar) are formed on the alveolar bone, which is derived from the maxillary process (termed herein as PALATE2). The aim of the present work was to analyze the variations in size and number of premolar and molar teeth in primate dentition and to correlate these morphometrical parameters with the relative size of these tooth classes with respect to PALATE2. Furthermore, we seek to understand to what extent the changes in the relative size of premolar and molar fields can influence the size of each tooth within its respective field, and how these parameters connect with the variations in the dental formula that occurred during primate evolution. The data presented here not only indicate that premolar and molar fields can be seen as submodules of a larger and hierarchically superior module (i.e., PALATE2) but also present quantitative parameters that allow us to understand how variations in the relative size of premolar and molar teeth connect with the variations in the dental formula that occurred during primate evolution.
将表型组装成模块或发育场，这些模块或发育场在发育和功能上是半自主的单位，似乎是增加产生表型变异能力的策略之一。在哺乳动物中，上齿列由两个不同的发育单位形成，其中切牙形成于初级腭，初级腭来自胚胎额鼻突，而其他牙齿（犬齿、前臼齿和臼齿）形成于牙槽骨，牙槽骨来自上颌突（本文称为 PALATE2）。本工作的目的是分析灵长类牙齿的前臼齿和臼齿的大小和数量的变化，并将这些形态参数与这些牙齿类相对于 PALATE2 的相对大小相关联。此外，我们试图了解前臼齿和臼齿域的相对大小的变化在多大程度上可以影响每个牙齿在其各自域中的大小，以及这些参数如何与灵长类进化过程中发生的牙齿公式的变化相联系。这里呈现的数据不仅表明前臼齿和臼齿域可以被视为更大的、层次更高的模块（即 PALATE2）的子模块，而且还提供了定量参数，使我们能够了解前臼齿和臼齿的相对大小的变化与灵长类进化过程中发生的牙齿公式的变化是如何联系的。
