Cane W Parker
Department of Ornithology, American Museum of Natural History, Central Park West at 79th Street, New York, New York, 10021.
Evolution. 1993 Aug;47(4):1138-1151. doi: 10.1111/j.1558-5646.1993.tb02141.x.
Empirical and theoretical work supports the concept that developmentally or functionally related characters tend to covary and hence evolve together. However, the dynamics of the developmental processes that establish within population covariance structures are not well understood. This paper focuses on a description of the relative growth of 16 postcranial skeletal elements during embryonic and posthatching development in the common tern, Sterna hirundo, and on a comparative analysis of ontogenetic and adult patterns of variation. Multivariate methods are used to assess the relative contributions of general growth and size-independent "shape" transformations during three major development phases. The observed patterns of integration generally correspond to functional units that tend to show greater relative growth during development immediately preceding when a unit will first be functionally required. Such age-dependent functional adaptations provide an opportunity for selection to act directly on ontogenies with consequences that will be age dependent. Size and shape contributions to adult covariances, which tend to be generated during different phases of development, appear to reflect ontogenetic integration patterns characteristic of periods when global constraints, such as overall size, are most relaxed, but more localized constraints, most likely linked to age-dependent functional requirements, are relatively intense.
实证和理论研究支持这样一种观点，即发育或功能相关的性状往往会共同变化，因此会一起进化。然而，对于在种群协方差结构中建立的发育过程的动态变化，人们还了解得不够透彻。本文着重描述了普通燕鸥（Sterna hirundo）胚胎期和孵化后发育过程中16个颅后骨骼元素的相对生长情况，并对个体发育模式和成年变异模式进行了比较分析。多变量方法用于评估三个主要发育阶段中总体生长和与大小无关的“形状”转变的相对贡献。观察到的整合模式通常与功能单元相对应，这些功能单元在首次需要发挥功能之前的发育阶段往往显示出更大的相对生长。这种与年龄相关的功能适应为选择直接作用于个体发育提供了机会，其结果将取决于年龄。对成年协方差的大小和形状贡献往往在发育的不同阶段产生，这似乎反映了个体发育整合模式的特征，即在总体大小等全局限制最为宽松，但最可能与年龄相关的功能需求相关的局部限制相对强烈的时期。
