Extended Data Fig. 8. Many virgins seem to learn retrieval from maternal demonstration.

a, Frequency of self-generated retrievals by dams. Top, example ethogram depicting two separate spontaneous retrievals by the dam (blue). Bottom, summary of individual dam spontaneous hourly pup retrieval rate per day (day one: 0.6±0.2 events/hour, day two: 0.3±0.1 events/hour, day three: 0.4±0.2 events/hour, day four: 0.4±0.2 events/hour, N=14). Lines, individual dam behaviour. Filled circles, daily average across animals. Dashed line, average rate of spontaneous retrieval for singly housed dams and litters without other adults (0.2±0.1 events/hour, N=5). Error bars, SEM. b, Virgin PVN responses when mother brought pups to virgin. For these animals, three separate pup delivery episodes occurred in a twenty-minute period after the second day of co-housing. On each of those occurrences, this PVN unit recorded in the virgin responded with increased spiking for several seconds until the dam returned to retrieve the pup herself. Top, raster of each of these three trials. Bottom, summary PSTH. Inset, spike waveforms; scale: 0.4 ms, 0.5 mV. c, Pup activity for non-co-housed virgins tested across transparent barrier, separated by virgins that began retrieving after observation (‘L’) and virgins that did not begin retrieving after observation (‘NL’). Left, pup movement (p=0.64, Student’s unpaired two-tailed t-test, N=16 animals: 3 learners, 13 non-learners). Middle, number of pup vocalizations (p=0.07). Right, pup call mean frequency (p=0.77). Error bars, SEM. d, Onset of retrieval behaviour was faster in co-housed virgins relative to non-co-housed virgins exposed to retrievals behind transparent barrier or with no barrier (Mantel-Cox test, p=0.004, N=48 mice total). **, p<0.01.