What does Dunbar’s group-living theory propose as the main driver of increased intelligence?

• A. Hunting large prey
• B. Maintaining social relationships and information exchange
• C. Tool-making complexity
• D. Climate change effects on society

Answer: (B)

The central idea is that intelligence evolves to manage social life. Dunbar’s group-living theory argues that as human groups become larger, individuals must juggle more complex social information—tracking who knows whom, who is allied with whom, reputations, trust, obligations, and how to coordinate with others. This ongoing social knowledge and the need to exchange information to maintain cohesion place greater demands on memory, planning, and communication, driving brain growth and higher cognitive ability. That focus on social relationships and information exchange is what makes this option the best answer. Other ideas—that hunting large prey, creating tools, or climate shifts drive intelligence—address different pressures, but they don’t capture the primary mechanism Dunbar emphasizes: social complexity shaping cognitive evolution.