Figure 2.

Schematic representation of possible direction of evolutionary change in phenotypic variation with respect to environmental sensitivity. Lines represent the reaction norms of target phenotypes (see text) and circles show the variation around the target phenotype. With respect to the central panel, the left panel depicts a situation with a higher developmental homeostasis, while the right panel depicts a situation with a higher environmental canalization (modified from Nijhout & Davidowitz 2003).