@article{96eca7514c6048b8b1a6f3c333a6d792,
title = "Bottlenose Dolphins Retain Individual Vocal Labels in Multi-level Alliances",
abstract = "Cooperation between allied individuals and groups is ubiquitous in human societies, and vocal communication is known to play a key role in facilitating such complex human behaviors [1, 2]. In fact, complex communication may be a feature of the kind of social cognition required for the formation of social alliances, facilitating both partner choice and the execution of coordinated behaviors [3]. As such, a compelling avenue for investigation is what role flexible communication systems play in the formation and maintenance of cooperative partnerships in other alliance-forming animals. Male bottlenose dolphins in some populations form complex multi-level alliances, where individuals cooperate in the pursuit and defense of an important resource: access to females [4]. These strong relationships can last for decades and are critical to each male's reproductive success [4]. Convergent vocal accommodation is used to signal social proximity to a partner or social group in many taxa [5, 6], and it has long been thought that allied male dolphins also converge onto a shared signal to broadcast alliance identity [5–8]. Here, we combine a decade of data on social interactions with dyadic relatedness estimates to show that male dolphins that form multi-level alliances in an open social network retain individual vocal labels that are distinct from those of their allies. Our results differ from earlier reports of signature whistle convergence among males that form stable alliance pairs. Instead, they suggest that individual vocal labels play a central role in the maintenance of differentiated relationships within complex nested alliances. Vocal convergence is frequently used to signal social proximity between individuals. King et al. show that multi-level dolphin alliances do not converge onto shared calls but retain individual vocal labels. This suggests that vocal labels play a central role in the recognition of cooperative partners and competitors in complex biological markets.",
keywords = "alliances, bottlenose dolphin, cooperation, male social relationships, signature whistles, vocal labels, vocal learning",
author = "King, {Stephanie L.} and Friedman, {Whitney R.} and Allen, {Simon J.} and Livia Gerber and Jensen, {Frants H.} and Samuel Wittwer and Connor, {Richard C.} and Michael Kr{\"u}tzen",
note = "Funding Information: S.L.K. was supported by The Branco Weiss Fellowship—Society in Science . S.L.K., R.C.C., and W.R.F. were supported by grants from the National Geographic Society ( 050R-17 and 9301-13 ). This study was supported by a Swiss National Science Foundation grant ( 31003A_149956 ) to M.K. W.R.F. was supported by a Graduate Fellowship in Anthropogeny from the University of California, San Diego . F.H.J. was supported by the US Office of Naval Research ( N00014-1410410 ) and an AIAS-COFUND fellowship from the Aarhus Institute of Advanced Studies, Aarhus University, under the EU{\textquoteright}s FP7 Programme (agreement no. 609033 ). Permits for the scientific use of animals were obtained from the Department of Biodiversity, Conservation and Attractions (DBCA), Western Australia. The University of Zurich and University of Western Australia granted animal ethics approvals. We thank RAC Monkey Mia Dolphin Resort, Monkey Mia Wildsights, and the DBCA{\textquoteright}s Shark Bay Rangers for their continued support and assistance. We thank all field assistants and our human judges for their help during this study. Lastly, we thank three anonymous reviewers for their valuable comments on the manuscript. Funding Information: S.L.K. was supported by The Branco Weiss Fellowship—Society in Science. S.L.K., R.C.C., and W.R.F. were supported by grants from the National Geographic Society (050R-17 and 9301-13). This study was supported by a Swiss National Science Foundation grant (31003A_149956) to M.K. W.R.F. was supported by a Graduate Fellowship in Anthropogeny from the University of California, San Diego. F.H.J. was supported by the US Office of Naval Research (N00014-1410410) and an AIAS-COFUND fellowship from the Aarhus Institute of Advanced Studies, Aarhus University, under the EU's FP7 Programme (agreement no. 609033). Permits for the scientific use of animals were obtained from the Department of Biodiversity, Conservation and Attractions (DBCA), Western Australia. The University of Zurich and University of Western Australia granted animal ethics approvals. We thank RAC Monkey Mia Dolphin Resort, Monkey Mia Wildsights, and the DBCA's Shark Bay Rangers for their continued support and assistance. We thank all field assistants and our human judges for their help during this study. Lastly, we thank three anonymous reviewers for their valuable comments on the manuscript. Publisher Copyright: {\textcopyright} 2018 Elsevier Ltd",
year = "2018",
month = jun,
day = "18",
doi = "10.1016/j.cub.2018.05.013",
language = "English (US)",
volume = "28",
pages = "1993--1999.e3",
journal = "Current Biology",
issn = "0960-9822",
publisher = "Cell Press",
number = "12",
}