Tail walking in a bottlenose dolphin community: the rise and fall of an arbitrary cultural ‘fad’

Abstract

Social learning of adaptive behaviour is widespread in animal populations, but the spread of arbitrary behaviours is less common. In this paper, we describe the rise and fall of a behaviour called tail walking, where a dolphin forces the majority of its body vertically out of the water and maintains the position by vigourously pumping its tail, in a community of Indo-Pacific bottlenose dolphins (). The behaviour was introduced into the wild following the rehabilitation of a wild female individual, Billie, who was temporarily co-housed with trained dolphins in a dolphinarium. This individual was sighted performing the behaviour seven years after her 1988 release, as was one other female dolphin named Wave. Initial production of the behaviour was rare, but following Billie's death two decades after her release, Wave began producing the behaviour at much higher rates, and several other dolphins in the community were subsequently sighted performing the behaviour. Social learning is the most likely mechanism for the introduction and spread of this unusual behaviour, which has no known adaptive function. These observations demonstrate the potential strength of the capacity for spontaneous imitation in bottlenose dolphins, and help explain the origin and spread of foraging specializations observed in multiple populations of this genus.

Integrating Genetic, Environmental, and Social Networks to Reveal Transmission Pathways of a Dolphin Foraging Innovation

“…Our results quantify non-vertical transmission of shelling, however, illustrating that free-ranging dolphins are also capable of learning foraging behavior outside the mother-calf bond. This builds upon previous cases of presumed horizontal transmission of behavior in toothed whales that were descriptive or anecdotal in nature [31][32][33]. Social learning opportunities increase with the duration and frequency of proximity between demonstrator and observer [34].…”

In search of animal normativity: a framework for studying social norms in non‐human animals

“…This capacity enables children first to understand each person's role in a collaborative activity and later to understand what 'we', qua group, demand from each other (Schmidt & Rakoczy, 2019;Tomasello, 2016aTomasello, , 2019. Birch (2021) proposed that the human normative sense is supported by model-based control systems that underpin expert performance in skilled action, such as tool manufacture, which involve standards for correct and incorrect performance (see also Sterelny, 2021). Still others have proposed that human norm psychology stems from basic domain-general processes, such as reinforcement learning, prediction-error minimization, and the maintenance of allostasis (Colombo, 2014;Theriault, Young & Barrett, 2021), or that norm psychology is a culturally evolved 'cognitive gadget' built upon domain-general foundations (Heyes, 2023).…”

“…For example, Theriault et al (2021) treat third-party punishment as a completely distinct mechanism for enforcing social conformity, existing in parallel with the force of social expectations. Meanwhile, Birch (2021) views third-party punishment as just one among many types of normatively regulated behaviour. Construed this way, third-party punishment only plays a peripheral role in the psychology of norms.…”

“…Henrich (2015) attributes 'the secret of our success' in part to a uniquely human 'norm psychology' shaped by a history of hominin gene-culture coevolution (see also Richerson & Boyd, 2005;Sripada & Stich, 2006;Kitcher, 2011;Kumar & Campbell, 2022). Recently, Birch (2021) and Sterelny (2021) have argued that social norms evolved from cognitive control mechanisms that were originally selected for complex tool manufacturing in hominins. While these proposals vary in their details, they share the common assumption that human beings are the only 'normative animal' (Roughley & Bayertz, 2019).…”

“…Social play and play fighting in species such as chimpanzees (Flack, Jeannotte & de Waal, 2004) and dogs (Bekoff, 2001) has been described as involving ‘rules’ governing play, signalling to potential rule enforcers, and modifying actions when playing with a younger or weaker partner. Instances of conformity to local cultural traditions, including traditions of tool preferences in chimpanzees (Luncz & Boesch, 2014; Whiten et al ., 2005), food preferences in vervet monkeys ( Chlorocebus pygerythrus ) (van de Waal, Borgeaud & Whiten, 2013), vocal traditions in birds and cetaceans (Aplin, 2019; Watson et al ., 2015; Whitehead & Rendell, 2015), as well as traditions of more arbitrary behaviour like chimpanzees wearing grass in their ear (van Leeuwen, Cronin & Haun, 2014) or dolphins tail‐walking (Bossley et al ., 2018) have been suggested as potential non‐human social norms. Apparent expectations about resource distribution, first identified in captive brown capuchin monkeys ( Cebus apella ) (Brosnan & de Waal, 2003), also invite descriptions in terms of protesting rule violations.…”