CEFE, University Montpellier, CNRS, EPHE, IRD, Montpellier, France.
LEPSE, University Montpellier, INRAE, Institut Agro, Montpellier, France.
Genetica. 2022 Aug;150(3-4):161-169. doi: 10.1007/s10709-022-00158-6. Epub 2022 Jul 20.
Phenotypic integration is a concept related to the cascade of trait relationships from the lowest organizational levels, i.e. genes, to the highest, i.e. whole-organism traits. However, the cause-and-effect linkages between traits are notoriously difficult to determine. In particular, we still lack a mathematical framework to model the relationships involved in the integration of phenotypic traits. Here, we argue that allometric models developed in ecology offer testable mathematical equations of trait relationships across scales. We first show that allometric relationships are pervasive in biology at different organizational scales and in different taxa. We then present mechanistic models that explain the origin of allometric relationships. In addition, we emphasized that recent studies showed that natural variation does exist for allometric parameters, suggesting a role for genetic variability, selection and evolution. Consequently, we advocate that it is time to examine the genetic determinism of allometries, as well as to question in more detail the role of genome size in subsequent scaling relationships. More broadly, a possible-but so far neglected-solution to understand phenotypic integration is to examine allometric relationships at different organizational levels (cell, tissue, organ, organism) and in contrasted species.
表型整合是一个与从最低组织层次（即基因）到最高层次（即整个生物体特征）的特征关系级联相关的概念。然而，特征之间的因果关系很难确定。特别是，我们仍然缺乏一个数学框架来模拟表型特征整合中涉及的关系。在这里，我们认为生态学中发展的异速生长模型为跨尺度的特征关系提供了可测试的数学方程。我们首先表明，异速生长关系在不同的组织尺度和不同的分类群中普遍存在于生物学中。然后，我们提出了一些机制模型来解释异速生长关系的起源。此外，我们强调，最近的研究表明，所有的生物体参数都存在自然变异，这表明遗传变异性、选择和进化的作用。因此，我们主张现在是时候研究异速生长的遗传决定因素了，以及更详细地探讨基因组大小在后续缩放关系中的作用。更广泛地说，理解表型整合的一个可能的——但迄今为止被忽视的——解决方案是在不同的组织层次（细胞、组织、器官、生物体）和对比物种中检查异速生长关系。
