Muséum National d'Histoire Naturelle, UMR CNRS 5202, Département Systématique et Evolution, 75005 Paris, France.
Evolution. 2009 Nov;63(11):2864-76. doi: 10.1111/j.1558-5646.2009.00774.x. Epub 2009 Jul 16.
The phenotypic effects of genetic and environmental manipulations have been rarely investigated simultaneously. In addition to phenotypic plasticity, their effect on the amount and directions of genetic and phenotypic variation is of particular evolutionary importance because these constitute the material for natural selection. Here, we used heterozygous insertional mutations of 16 genes involved in the formation of the Drosophila wing. The flies were raised at two developmental temperatures (18 degrees C and 28 degrees C). Landmark-based geometric morphometrics was used to analyze the variation of the wing size and shape at different hierarchical levels: among genotypes and temperatures; among individuals within group; and fluctuating asymmetry (FA). Our results show that (1) the phenotypic effects of the mutations depend on temperature; (2) reciprocally, most mutations affect wing plasticity; (3) both temperature and mutations modify the levels of FA and of among individuals variation within lines. Remarkably, the patterns of shape FA seem unaffected by temperature whereas those associated with individual variation are systematically altered. By modifying the direction of available phenotypic variation, temperature might thus directly affect the potential for further evolution. It suggests as well that the developmental processes responsible for developmental stability and environmental canalization might be partially distinct.
遗传和环境操作的表型效应很少被同时研究。除了表型可塑性外，它们对遗传和表型变异的数量和方向的影响具有特殊的进化意义，因为这些构成了自然选择的材料。在这里，我们使用了参与果蝇翅膀形成的 16 个基因的杂合插入突变。这些苍蝇在两种发育温度（18°C 和 28°C）下饲养。基于地标几何形态计量学用于分析不同层次的翅膀大小和形状的变异：在基因型和温度之间；在组内个体之间；以及波动不对称（FA）。我们的结果表明：（1）突变的表型效应取决于温度；（2）相反，大多数突变影响翅膀的可塑性；（3）温度和突变都改变了 FA 的水平和线内个体间的变异。值得注意的是，形状 FA 的模式似乎不受温度影响，而与个体间变异相关的模式则被系统地改变。通过改变可用表型变异的方向，温度可能直接影响进一步进化的潜力。这表明负责发育稳定性和环境 canalization 的发育过程可能部分不同。
