Allied male dolphins use vocal exchanges to “bond at a distance”

• DOI: 10.1016/j.cub.2022.02.019
• Publication Date: 2022-03-25T01:23:09Z
• Authors: Emma Chereskin; Richard C. Connor; Whitney R. Friedman; Frants H. Jensen; Simon J. Allen; Pernille M. Sørensen; Michael Krützen; Stephanie L. King
• Keywords: Social contact

Vocal interactions are intrinsic features of social groups and can play a pivotal role in bonding.1,2 Dunbar's bonding hypothesis posits that vocal exchanges evolved to "groom at distance" when became too large or complex for individuals devote time physical activities.1,3 Tests this non-human primates, however, suggest occur between more strongly bonded engage higher grooming rates4-7 thus do not provide evidence replacement bonding. Here, we combine data on bond strength, whistle exchange frequency, affiliative contact behavior rates test wild male Indo-Pacific bottlenose dolphins, who form multi-level alliances cooperate over access females.8-10 We show that, although likely within the core alliance, they frequently those males share weaker bonds, i.e., allies spend less together, while opposite occurs behavior. This suggests function as low-cost mechanism dolphins close proximity fewer behaviors reinforce maintain their valuable alliance relationships. Our findings new outside primate lineage serve reveal originally suggested, activities important