Cooperation in bottlenose dolphins: bidirectional coordination in a rope-pulling task

Abstract

In comparison with terrestrial animals, such as primates, there is limited empirical evidence for cooperative behavior in marine mammals under experimental conditions. In this study, we used a cooperative rope-pulling task to investigate how bottlenose dolphins (Tursiops truncatus) coordinate their behavior with a partner. Dolphins successfully learned and were able to perform the task, even when one subject started after the other. In the no-delay condition (i.e., both subjects sent at the same time), one pair of dolphins showed coordinated behaviors. When pairs were successful in solving the task in the delay condition (i.e., one individual sent later than the other), the initiators (i.e., first individual sent) were likely to wait for the follower to arrive, and the follower was likely to swim faster when the initiator did not wait and started pulling the rope alone. These coordinated behaviors might help resolve the given cooperative task. Our results suggest that bottlenose dolphins learn to coordinate their behaviors via trial and error and recognize the necessity of performing simultaneous actions with a partner to successfully accomplish cooperative tasks. In addition, both partners showed behavioral changes over many trials of no-delay and delay conditions, suggesting that bidirectional coordination occurred in the cooperative task.

How animals collaborate: Underlying proximate mechanisms

“…The measure of interest is whether or not the subject inhibits pulling until the partner is ready to pull. So far, there is evidence that chimpanzees, elephants (Elephas maximus), kea (Nestor notabilis), dolphins (Tursiops truncatus), and wolves learn to wait for the partner (Heaney, Gray, & Taylor, 2017;Marshall-Pescini, Schwarz, Kostelnik, Virányi, & Range, 2017;Melis et al, 2006;Plotnik et al, 2011;C. Yamamoto, Kashiwagi, Otsuka, Sakai, & Tomonaga, 2019).…”

“…From the species that have been successful in the delayed loose-string task, including chimpanzees, elephants, wolves, dolphins, and kea (Hirata & Fuwa, 2007;Jaakkola et al, 2018;Marshall-Pescini et al, 2017;Melis et al, 2006;Plotnik et al, 2011;C. Yamamoto et al, 2019), it is clear that this is something that requires some learning.…”

A water-reward task assay for evaluating mouse mutualistic cooperative behavior

“…Cooperation is a complex behavior with an intrinsic social dimension and at the same time requires certain levels of cognitive abilities. Many experimental studies are conducted with nonhuman primates and dolphins, in which animals are expected to pull a rope or handles or push buttons 9-11 . Rats are prosocial animals and are found to show generalized altruistic behavior, making it another excellent model for studying cooperative behavior 2,12 .…”