Figure 2.
Effect of the time frame for reciprocating grooming on the symmetry in grooming reciprocation. The relationship between grooming given and received was significant in the three analyses (within bouts: b±CI=0.63±0.08, t400=18.26, p<0.0001; within days: b±CI=0.61±0.08, t343=15.46, p<0.0001, dyadic long term: b±CI=0.83±0.08, t151=16.16, p<0.0001). The overlap of confidence intervals (CI) between the within-bouts and within-days analyses indicates that the differences in the symmetry in grooming reciprocation were not significant. The lack of overlap of CI between the dyadic long-term and other two analyses indicates that these differences were significant. (*** indicates p<0.0001.)