For different types of environmental conditions, the logarithmic changes in each concentration Xj, denoted by δXj(E), are proportional for almost all components, over a wide range of perturbations, where the proportionality coefficient is given by the ratio of change in cell growth rate δμ(E). Then consider the evolution after applied environmental changes. Let the change in log concentration be δXj(G) and the change in growth rate be δμ(G). The theory suggests that δX_j(G)/ δX_j(E)= δμ(G)/ δμ(E), as confirmed experimentally. With evolution, the right hand term gradually moves toward 0, accordingly the change in concentrations does. This is a process similar to the Le Chatelier principle of thermodynamics. The relationships described above arise because phenotypic changes due to environmental perturbations, noise, and genetic changes are constrained to a common low-dimensional manifold as a result of evolution. This is because the adapted state after evolution should be stable against a variety of perturbations, while phenotypes retain plasticity to change, in order to have evolvability. To achieve this dimensional reduction, there is a separation of a few slow modes in the dynamics for phenotypes. The variance of phenotypes due to noise and mutation is proportional over all phenotypes, leading to the possibility of predicting phenotypic evolution.