  Recent advancements in generative artificial intelligence (AI) have
transformed collaborative work processes, yet the impact on team performance
remains underexplored. Here we examine the role of generative AI in enhancing
or replacing traditional team dynamics using a randomized controlled experiment
with 435 participants across 122 teams. We show that teams augmented with
generative AI significantly outperformed those relying solely on human
collaboration across various performance measures. Interestingly, teams with
multiple AIs did not exhibit further gains, indicating diminishing returns with
increased AI integration. Our analysis suggests that centralized AI usage by a
few team members is more effective than distributed engagement. Additionally,
individual-AI pairs matched the performance of conventional teams, suggesting a
reduced need for traditional team structures in some contexts. However, despite
this capability, individual-AI pairs still fell short of the performance levels
achieved by AI-assisted teams. These findings underscore that while generative
AI can replace some traditional team functions, more comprehensively
integrating AI within team structures provides superior benefits, enhancing
overall effectiveness beyond individual efforts.
