Gene networks highly correlated with seasonal body size plasticity. (A) Gene expression correlations form 37 modules. Eleven of these modules were significantly correlated with shrew body size. (B) Clustering of significant genes across seasons (LRT, P_adj < 0.05) revealed a cluster of genes (cluster 4) with upregulation during shrinking seasons. The largest proportion of these genes overlapped with the red gene network. (C) Pathway enrichment of the large (n = 3268 genes) “red” module highlighted functional associations to FOXO signaling and insulin resistance (plotted genes), which are associated with longevity regulating pathways.