Figure 1.

Timeline of the experimental design. Birth and weaning events are indicated with vertical dashed lines. Arrows indicate timing of recordings and playbacks with averages and ranges (d, days; m, months). The full experiment, from the birth of previous kids to the second series of playbacks, lasted 14 months on average, depending on the goats (range 12–18 months). ‘Playbacks 1’ correspond to playbacks of previous kid calls at five weeks postpartum. ‘Playbacks 2’ correspond to playbacks of these same calls at 12–18 months postpartum (7–13 months after weaning), and to playbacks of calls from familiar kids, born 9–39 days previously. Goats were nursing new kids at the time of the study (current kids).