Figure 4.

Principal component analysis (PCA) separates controls, guards and nurses based on normalized immediate early gene expression in the four regions of the honeybee olfactory pathway analysed in this study (figure 1 and Methods). We included normalized expression of (a) hr38 and (b) egr1 in the antennal lobe, Class I Kenyon cells (inner compact + non-compact) and Class II Kenyon cells (outer compact). Analyses were conducted at 15 min post-assay, where we found peak hr38 and egr1 expression. Largest shape denotes centroid for each group. n = 9–15 bees per group. (Online version in colour.)