Cooperative Action

Determining whether an animal species has the capacity to perform cooperative tasks with other members of its species can give us evidence for the following abilities:

• recognizing others of its species
• mentally representing the capabilities or aspects of other animals
• recognizing the cooperative task goals, task demands, and the roles of the animals in the solution
• communicating to join task or what to do
• reciprocal altruism

A standard task involves two animals having to perform the same action on an apparatus (typically pulling on a rope or object) to receive a reward. If only one performs the action, no reward is obtained. This task has been performed with many primates, with a strong focus on capuchin monkeys and chimpanzees to compare and contrast social monkeys and apes.

Capuchins

• Solve, Fail to understand: They succeed in the task because they tend to interact with the device in a similar way and have high social tolerance. There was no timing of events to sync with others and success was from chance occurrence of performing the same action at the same time. the handles were not attached physically to the food and the food was distant, being delivered after pulling.
• Solve, but don't represent the actions of other agents: There was no difference in how they pulled when the partner was on or off the platform, but there was a difference in pulling depending on whether the partner was close or far from the handle while on the platform. No difference in pulling was found when the partner was pulling. The handles to pull were not physically attached to the platform with food.
• Solve: In the task where the two necessary actions are sequential, the first capuchin looks more often at the second capuchin to get it to perform its action, showing that it knows the role of the other.
• Solve, represent the location of other agents: Success was hampered by not being able to see the other monkey. The food was on a platform that was physically linked to pulling devices - a more natural movement and task.

Chimpanzees

• Solve but did not interact with partner to solicit synchronized behavior. The chimpanzees did, however, wait to pull on the rope until their partner did so. This indicates their awareness of the task requirements.
• Solve. The older male chimpanzee would wait to pull on the rope until the infant pulled the rope. This provides evidence that chimpanzees can represent activity of other in task.

Orangutans

Solve. As with chimps, the coordination was done by only one individual, who waited and pulled when the other pulled. This provides evidence that they can represent the role of another agent in task.

Cotton-top tamarin

Solve.

Marmosets

Solve. The task did not have equal roles and the success of pairs depended on the rank of the animal in each role and how much lower ranked animals could tolerate higher ranked animals.

While cooperation tasks can provide possible evidence for which primates have theory of mind capabilities, there is evidence that a number of other species can solve these tasks. These species tend to be very social. Hyenas, elephants, and African grey parrots have had success.