Data from: Cryptic individual scaling relationships and the evolution of morphological scaling

Morphological scaling relationships between organ and body size—also known as allometries—describe the shape of a species, and the evolution of such scaling relationships is central to the generation of morphological diversity. Despite extensive modeling and empirical tests, however, the modes of selection that generate changes in scaling remain largely unknown. Here, we mathematically model the evolution of the group-level scaling as an emergent property of individual-level variation in the developmental mechanisms that regulate trait and body size. We show that these mechanisms generate a "cryptic individual scaling relationship" unique to each genotype in a population, which determines body and trait size expressed by each individual, depending on developmental nutrition. We find that populations may have identical population-level allometries but very different underlying patterns of cryptic individual scaling relationships. Consequently, two populations with apparently the same morphological scaling relationship may respond very differently to the same form of selection. By focusing on the developmental mechanisms that regulate trait size and the patterns of cryptic individual scaling relationships they produce, our approach reveals the forms of selection that should be most effective in altering morphological scaling, and directs researcher attention on the actual, hitherto overlooked, targets of selection.

器官与体型之间的形态缩放关系——亦称异速生长关系（allometry）——刻画了物种的形态特征，而这类缩放关系的演化是形态多样性产生的核心驱动因素。尽管已有诸多建模与实证检验研究，但驱动缩放关系发生改变的选择作用模式，在很大程度上仍未明确。本研究以数学建模的方式，将种群水平的缩放关系演化，刻画为调控性状与体型的发育机制在个体层面存在变异所产生的涌现属性。我们发现，这类发育机制会催生种群内每种基因型所独有的「隐秘个体缩放关系」，该关系会根据个体发育过程中的营养状况，决定每个个体最终表现出的体型与性状大小。我们的研究结果显示，不同种群即便拥有完全一致的种群水平异速生长关系，其背后的隐秘个体缩放关系模式可能存在显著差异。因此，即便两个种群的形态缩放关系外观一致，它们对同一类型的选择作用可能会产生截然不同的响应结果。本研究聚焦于调控性状大小的发育机制，以及这些机制所催生的隐秘个体缩放关系模式，由此明确了在改变形态缩放关系方面最为有效的选择作用类型，并将研究者的注意力引导至迄今被忽视的真实选择作用靶点之上。