Still images of a trio (first-order alliance BIG, FRE and RID) of male dolphins (♂) and their female consort (♀DUC) taken from drone-mounted video footage at the time of playback (T-0). Subsequent images at 3 s (T + 3), 20 s (T + 20) and 30 s (T + 30) after we played the signature whistle of their absent second-order ally (NAT). Animal orientation is identified by the arrows. Male RID turned immediately back towards the sound source (180°) and produced his signature whistle in response at T + 3 (see also Supplementary Fig. 2), after which, BIG, FRE and female DUC also turned (T + 20), before starting to veer away (T + 30). Source data are provided as a Source data file.