marginally significantp = 0.049
The three-way interaction among site, treatment and client body size was marginally significant (N = 2 177 client interactions, GLMM: χ 2 = 3.86, p = 0.049; Fig. 2 , Supplementary Table S1 ): Cortisol-treated cleaners gave more TS to small clients than saline-treated cleaners but only in high social complexity habitats (Supplementary Figure S3 ).