Figure 1

General patterns of gene expression in the larval midgut of Polygonia c-album. Dark grey represent qualitative differences or similarities (present/absent), light grey represent quantitative differences or similarities (more/less). (a) The number of uniquely upregulated genes on the three host plants used in the study, showing that significantly fewer genes were uniquely upregulated on Ulmus. (b) Pairwise similarities in upregulation between two of the three host plants. "Urticalean rosids" = Urtica dioica + Ulmus glabra; "Trees" = Ulmus glabra + Salix caprea; "No connection" = Urtica dioica + Salix caprea. Following predictions, more genes were concurrently upregulated on plants that shared either ancestry or growth form.