Girls (and women) tend to hang out in cliques, while boys (and men) tend to be more individualistic. This may have evolutionary origins. as women try to have have very good friends to insure that their offspring is taken care off should they die. Men do not directly have such a need, and may have several wives who continue to take care of their offspring should the man die. Does this attitude translate into the workplace?
Peter Kuhn and Marie Claire Villeval conduct a experiment where people need to exert effort, but can do it by choice individually or in a team. Women are then more likely to choose the team. Once there is an extra reward in efficiency for working in a team, both genders choose the latter in equal proportions. Still, the most able players tend to work alone. This can be interpreted as men being more responsive to incentives and women having more confidence in team work. Unfortunately, the study does not differentiate between same-gender and cross-gender pairings (gender was visible in the experiment).