Efficiency quantifies how close agents were to the direct path from start to goal.

Final efficiency is measured in the last generation and generational increase as the difference between generations. Cumulative route improvements are reflected by a positive intergenerational increase and occur in the “experimental” condition (“pair” and “solo” are control conditions). The “no lesion” column reflects optimal scores; the other columns reflect scores after replacing the goal, social, memory, or continuity component with a uniform distribution (noise).