We experimentally investigate the effect of social identification and information feedback on individual behavior in contests. In contrast to standard theoretical predictions, we find significant over-expenditure of efforts in all treatments. Identifying subjects through photo display decreases efforts. We develop a behavioral model based on social identity explaining how a decrease in ‘social distance’ between group members through photo display promotes prosocial behavior. Providing information feedback about others’ effort does not affect the aggregate effort levels but changes the dynamics of individual behavior by facilitating greater adherence to the ‘group norm.’ Finally, we find that significant over-expenditure can be explained by a combination of non-monetary utility of winning and relative payoff maximization.