Classical models of the emergence of compositionality in communication focused on the compositional nature of the en-vironment (Cangelosi, 2001; Cornish et al., 2008). Here we advance a model in which compositional structure emergesfrom integrating environments properties with agents actions. We take as a starting point Cangelosis (2001) model, wherea population of agents searched for edible mushrooms. Given opportunity to communicate, they evolved a system inwhich combinations of signs were sensorily grounded in combinations of mushroom properties. We modify this modelby grounding the communication also in agents’ actions. With this, we are able to evolve communication systems con-taining meaningful compositions of mushroom properties and agent actions. We investigate how such compositions canfacilitate a) learning the communication protocol, b) learning the adequate behavior policy. This kind of sensory-motorcompositionality seems better suited for coordinating navigation in dynamic environments.

Abstraction lies at the heart of human cognition. While most approaches to abstraction implicitly take the individual as astarting point, we hypothesize abstraction to be contingent on the interactive sharing of diverse perspectives. Interactivealignment, however, can reduce diversity making group members’ contributions more similar and redundant, especially ifthey have not had time to form their own impressions and opinions. We report an experiment investigating the conditionsunder which participants arrive at a superior, abstract rule-based solution to a problem: inferring the direction of the lastgear from the rotation of the first in a series of connected gears. Participants were assigned to three different conditions:1) individual, 2) dyadic, 3) combined: dyad members start individually but are joint mid through the experiment. We findthat performance is significantly higher in the dyadic than in the individual condition, but highest in the combined.