Limited influence of habituation time and cage shape/size on the time spent in contact.

Time in contact (< 1 cm) was measured during the first 4 min of interaction after 20 min (left panel) or 30 min (right panel) habituation time in three cage types. (Wilcoxon-Mann-Whitney U-tests: n = 8 pairs of mice per condition; *: p<0.05; data are presented as mean +/- sem).