3 or more people together in some captivity. They dont need to be interacting with each other. Seeing how if ppl are just in a room w you, how you act. We have specific norms in place for our groups. Written rules about how you should behave. Being in a group can help us find a mate. Ie. someone can help us in the future. When we end up like a better or stronger way then we would have without the people we have around us. Occurs when we work alone but in tge presence of an audience. Ie. running alone, you may run slower alone but run faster next to people. Performance will be enhances on simple, well-learned tasks, and dimeshed on novel/complex task. Cycling: individual times are slower than group times. Kids alone were much slower than kids in groups. Conclusion: everything improves in the presence of others. But: something we do worse in groups than alone.