Figure 10.

Results of resident–intruder trials. Numbers 1,2,3 represent 10 min trials 1 week apart. No significant differences were found in the frequency of social behaviour between the two genotypes (a). The duration of sniffing decreased significantly in both groups during the subsequent trials, although relevant temporal differences were detectable only in KOs (b). Neither the frequency nor the duration of aggressive interactions were significantly altered by time or by genotype (c,d). n = 12 in both groups, * p < 0.05 and ** p < 0.01 show a significant difference between repeated trials in the same group. Blank triangles represent individual values while dark spots show outliers (characterized by a higher or lower value than mean ± 2 standard deviation (SD)).