Extended Data Fig. 3. Shepherding behaviour.

a, Average latency for dams to shepherd virgin to the nest (time 0 is virgin nest exit). Latency decreased over days of co-housing (day 1: 155.9±34 s; day 2: 136.1±17.94 s; day 3: 75.7±5.5 s; day 4: 93.9±8.5 s; n=676 events from N=9 dam-virgin pairs, p<0.0001, one-way ANOVA, Holm-Sidak’s multiple-comparison test). Red lines, medians. Error bars, SEM. b, Left, ethograms from two separate virgins, one co-housed just with dam without pups (top), the other co-housed with dam and pups (bottom). Note differences between time in nest and amount of shepherding when pups were present. Right, summary of shepherding events per hour when pups were removed vs when pups were present (‘No pups’: 0.2±0.1 events/hour; ‘Pups’: 3.5±0.9 events/hour, N=4, p=0.03, Student’s two-tailed paired t-test). Error bars, SEM. c, Locations of start (yellow) and end (orange) positions of dam→virgin chasing events without pups in the cage (N=4 dyads), relative to nest center (nest radius was ~10 cm, gray). 46.1±10.4% of dam→virgin chases ended in the nest, indicating that the frequency of these chases was significantly reduced but the direction of the virgins was comparable with or without pups (all chasing events ending in nest, p=0.9, two-sided Fisher’s exact test).