Emergence of Joint Action in Bonobos & Children

Building blocks of human sociality: A comparative assessment of joint action in humans and their closest ape relatives

Many social animals collaborate, but only humans supposedly engage in joint action – cooperative interactions that involve normative, mutually obligating joint commitments (JCs). This enabled the evolution of hyper-cooperation observed in human societies, including complex collaborations like governments, and has likely played a pivotal role in human evolution. Given the significance, there has been a long-standing interest in the ontogenetic and evolutionary origins of joint action capacities like JC. 

The classical approach employed experiments with human children and nonhuman great apes, showing that while humans engage in joint actions, apes’ interactions rely on egoistic motives. However, such tasks are highly anthropocentric, involving engagement with human confederates in human-centric tasks. 

Conversely, drawing on a more ecologically valid approach, this research demonstrates that when apes interact with other apes naturally, they appear to exhibit specific joint action capacities like JC. Yet firm conclusions cannot be drawn unless the following empirical issues are solved:

• behaviours do not permit insights into internal mechanisms facilitating social success and cooperation,

• comparative joint action research is still in its infancy, lacking a holistic picture of affective and behavioural processes supporting coordination, and 

• previous ape studies are deficient of critical experimental controls and technological tools to quantify fast-paced social behaviours in naturalistic interactions. 

This Marie Curie project overcomes these challenges by pioneering a comparative investigation of spontaneous joint action coordination in human children and bonobos. Using cutting-edge tracking and thermal imaging techniques, as well as timely controls, the project explores pivotal joint action signatures like communicative repair, bodily synchrony, and JC-related emotional expressions. This offers a powerful assessment of the hypothesis that humans  and apes share fundamental joint action capacities, highlighting evolutionary continuity and dissecting the building blocks of human cooperative sociality.