Fig. 4

Higher olfactory sensitivity to cuticle extract in majors compared to minors aligns with more severe aggression towards non-nestmates. A Solvent (hexane) normalized EAG responses showing that both minors and majors exhibited robust, dose-dependent excitatory responses to cuticle extract from non-nestmate minor workers (n=5; individual data values can be found in Additional file 9). Dots represent the mean response and error bars represent S.E.M. The lines are best fit dose response curves. B Schematic of the bioassay depicting the acclimation period (top) and aggression bioassay (bottom). C A heat map showing the elapsed time of the 3-min aggression bioassay along the X-axis. The heat map represents the proportion of trials where aggression was observed at each time point for nestmates (NM) and non-nestmates (nNM) in trials conducted with majors vs. majors (MvM), majors vs. minors (Mvm), and minors vs. minors (mvm) (n=10–11). The mean time at which dismemberment (droplet) or death (skull and crossbones) occurred is indicated along the heat map. Notably, minor vs. minor bouts never resulted in dismemberment or death. D The mean aggression duration (in seconds) between nestmates and non-nestmates (n=10–11; two-way ANOVA with Tukey’s correction, P-value: ns = not significant, * < 0.05, **** < 0.0001). E, F The percentage of trials that resulted in at least one instance of dismemberment or death (n=10–11, z-test with Bonferroni’s correction, P-value: * < 0.016)