Figure 1.

Diagram of a traditional common garden experiment (a) compared to the transgenerationally extended common garden experiment (b) utilized in this study. Both experimental designs allow genetic, environmental, and genetic × environmental effects to be parsed out through norms of reaction and associated analyses. The extended transgenerational approach utilizing an experimental generation (b), allows for transgenerational effects to be considered within this this framework. This framework allows transgenerational plasticity (c.i) to be considered alongside traditional within generation plasticity (c.ii) to study damage induced trichome production in M. guttatus. While constitutive trichome densities are expected to evolve in accordance with mean herbivore abundance at a given site (d.i), it is the presence or absence of inter-annual autocorrelations in herbivore abundance that are expected to select for or against transgenerational plasticity of trichome induction (d.ii).