Nemeschkal Hans L
Institute of Zoology, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria.
Evolution. 1999 Jun;53(3):899-918. doi: 10.1111/j.1558-5646.1999.tb05384.x.
Stimulated by the rapid progress in developmental genetics, recent approaches to evolutionary theory focus on the interface function of developmental processes in the study of genotype-phenotype mapping. From this viewpoint, the main result of the present analysis is that the expression patterns of developmental control genes are reflected in the infraspecific correlation patterns of phenotypic characters in the adult stage. The study is based on 42 logarithmically scaled skeletal measurements of two avian clades, finches (43 species, n = 313) and pigeons (27 species, n = 219). First, for each clade an "observed correlation matrix" was calculated by computing a bias-reduced pooled-species correlation matrix based on the clade-specific pooled within-species variance-covariance matrix between measurements. Second, the expression domains of diverse developmental control genes, that is, Hox, Msx, Pax, Mhox, Shh, Bmp, and Gdf, in characters were represented by "theoretical matrices." Finally, the observed and the theoretical matrices were compared by Mantel's test to test hypotheses about pattern similarities between phenotypic correlations and the expression of developmental control genes. Seventeen percent of the single matrix comparisons revealed significant (P ≤ 0.05) pattern correspondences in finches, whereas 63% were significant in pigeons. The multiple comparisons revealed correspondences at the highest significance level (P ≤ 0.001) in both clades and disclosed that 15% of the observed matrix patterns are explained in finches versus 22% in pigeons. Presumably, as finches have less pronounced correspondences between gene expression and phenotypic correlation, they are more derived than pigeons. Out of the significant single matrix comparisons, four correspondences are common to both clades: one of them is connected with the Gdf gene expression concerning limb length relations and also harmonizes with the dominant pattern within the infraspecific correlation matrices. The general implication is that the significant correspondences detected here between observed and theoretical matrices are based on a correspondence between phenotypic and genetic modules. Because the phenotypic modules are potential candidates for a direct impact of selection, the important role of genotype-phenotype mapping in molding the body plan becomes apparent.
受发育遗传学快速发展的刺激，近期进化理论的研究方法聚焦于发育过程在基因型 - 表型映射研究中的界面功能。从这个观点来看，本分析的主要结果是发育控制基因的表达模式反映在成年期表型特征的种内相关模式中。该研究基于对两个鸟类分支（雀类，43种，n = 313；鸽类，27种，n = 219）的42个对数尺度的骨骼测量数据。首先，对于每个分支，通过基于测量之间特定分支的种内方差 - 协方差矩阵计算偏差减少的合并物种相关矩阵来计算“观察到的相关矩阵”。其次，不同发育控制基因（即Hox、Msx、Pax、Mhox、Shh、Bmp和Gdf）在特征中的表达域由“理论矩阵”表示。最后，通过Mantel检验比较观察到的矩阵和理论矩阵，以检验关于表型相关性与发育控制基因表达之间模式相似性的假设。在雀类中，17%的单个矩阵比较显示出显著（P≤0.05）的模式对应，而在鸽类中这一比例为63%。多重比较显示两个分支在最高显著水平（P≤0.001）上存在对应关系，并表明雀类中15%的观察到的矩阵模式可以得到解释，而鸽类中这一比例为22%。据推测，由于雀类在基因表达与表型相关性之间的对应关系不太明显，它们比鸽类更为进化。在显著的单个矩阵比较中，有四个对应关系在两个分支中都存在：其中之一与Gdf基因表达有关肢体长度关系，并且也与种内相关矩阵中的主导模式一致。总体而言，这里观察到的矩阵和理论矩阵之间检测到的显著对应关系是基于表型和遗传模块之间的对应。因为表型模块是选择直接影响的潜在候选者，基因型 - 表型映射在塑造身体结构中的重要作用变得明显。
