Pros and cons of sociality across ecological niches: a swarm robotics approach.

The evolution of language is closely linked to an increase in human sociality. But when is increased sociality an adaptive strategy? Swarm Robotics, which studies the collective behaviors of large populations of interacting robots with simple embodied cognition, is an ideal testbed for studying the environmental conditions that may favor the evolution of more social behaviors and cooperative language. Here, we introduce the notion of parametrizable sociality to classic swarm robotics models, and test the foraging and communication behaviors of robots with different degrees of sociality under different environmental conditions, which have been previously implicated in eliciting this increase in prosocial behavior in human history. Our results show that in abundant environments with plenty of resources, higher innate sociality is consistently beneficial only in the absence of aggressive competition. Nevertheless, social agents typically outperform aggressive agents in the short-term in both abundant and scarce environments. In scarce environments with fewer resources, this short-term advantage is especially beneficial as it enables agents to forage as much food as possible before depletion. Together, our results suggest that sociality provides an evolutionary advantage in specific conditions, which maps to the potential ecological niches in which early humans have evolved.