Figure 1.

The influence of relationship quality and recent grooming on urinary oxytocin levels (n = 33 subjects, n = 137 samples). Urinary oxytocin levels following a single bout of grooming (more than 10 min) with a genetically related bond partner, an unrelated bond partner, a non-bond partner or following resting or feeding (control). Box plots show median and quartiles, whiskers show the 95% CI, and circles indicate values >95% CI. Differences across behavioural conditions: *p < 0.05 (table 1b).