 Individuals belonging to other speech communities may also adopt languages from a different language family through the language shift process.Genealogically related languages present shared retentions; that is, features of the proto-language (or reflexes of such features) that cannot be explained by chance or borrowing (convergence).Membership in a branch or group within a language family is established by shared innovations; that is, common features of those languages that are not found in the common ancestor of the entire family.