A myriad of studies reveal that groups created on common bonds and common identities may both generate strong commitments, but in different ways. For example, common bond groups may elicit higher levels of interest in the individual group members and in within-group communications while common identity groups may treat individual group members as relatively interchangeable.
At this point, the preservation of homogeneity stands for an imperative in order to maintain unity in these groups (Farzan et al., 2011). Despite the existence of many similarities, social psychological research frequently deems that these two types of groups cannot be combined with each other. It is assumed that overestimating the presence of individuals may afflict the common identity and overestimating the presence of the group as a whole may afflict common bonds (Turner, 1991; Postmes, Spears & Lea, 1998; Sassenberg, 2002).
Analyzing varied prerequisites for the influence in groups based on interpersonal bonds, most researchers have demonstrated that common-bond and common-identity groups had very different dynamics: in the former type of group, influence arises from diversity of views and disagreement, whereas in the latter type of group, influence arises from coherence and consensus (Sassenberg & Postmes, 2002).
Future research is expected to identify many other contingencies that determine whether group membership is compatible or incompatible with expressions of individuality. These aspects comprise the norms and dynamics of the group, the comparative context, the relative size of the group, and the component of individuality that is salient.