Data from: Grain of environment explains variation in the strength of genotype × environment interaction

Theory predicts that genetic variation in phenotypic plasticity (genotype
× environment interaction, or G×E) should be eroded by selection acting
across environments. However, it appears that G×E is often maintained
under selection, although not universally. This variation in the presence
and strength of G×E requires explanation. Here I ask if the explanation
may lie in the grain of the environment at which G×E is expressed. The
grain (or grain–size) of the environment refers to the scale of
environmental heterogeneity relative to generation time — i.e., relative
to the window of operation of selection — with higher rates of
heterogeneity occurring in finer–grained environments. The hypothesis that
the grain of the environment explains variation in the expression of G×E
encapsulates variation in the power of selection to shape reaction norms:
selection should be able to erode G×E in fine–grained environments but
loose its power as the grain becomes coarser. I survey studies of G×E in
sexual traits and demonstrate that the strength of G×E varies with the
grain of the environment across which it is expressed, with G×E being
stronger in coarser–grained environments. This result elucidates when G×E
is most likely to be sustained in the reaction norms of fitness–related
traits, and when its evolutionary consequences will be most pronounced.