Figure 5.

Summary of evidence between measures of glucocorticoids (GCs) and nonsexual pair‐bonding behavior in wild vertebrates. Most studies support our prediction that GCs have a positive effect on pair‐bonding behavior (affiliation) where increased affiliative behavior between two conspecific is associated with a subsequent reduction in GCs (Affiliation effects on GCs). Some studies also supported the prediction that elevations in GCs caused an increase in the expression of nonsexual pair‐bonding behavior (GCs effect on affiliation). Counts are comparisons where any measure of GCs and nonsexual bonding behavior were investigated and in some cases there was more than one comparison per study (see Table S3)