Macro-diversity and intergroup attitudes

Due to increased immigration, many Western societies are becoming increasingly ethnically diverse. Since the successful integration of immigrants is one of the key challenges faced by receiving societies and has become a major policy issue in many host countries (Castles et al., 2020; International Organisation for Migration, 2019), it is unsurprising that the anticipation of potential consequences of this increase in ethnic and cultural diversity has fuelled extensive societal and political, as well as academic, debate. The central question herein is thus whether ethnic diversity is good or bad for receiving societies, communities/neighbourhoods, and individuals - that is, whether diversity has positive or negative consequences on a range of outcomes. In this chapter, we focus on whether diversity at a macro level (that is, diversity of individuals' social contexts) is beneficial or disadvantageous for intergroup attitudes. Our aim is to review research in political and social psychology on the consequences of macro-diversity for majority members of the host societies, focusing particularly on social trust, intergroup attitudes, and political behaviour. We start by conceptualising macro-level diversity and outlining some methodological considerations. Next, we briefly review the evidence on the question whether ethnic diversity has positive or negative consequences for intergroup relations. We then focus on two potential psychological mechanisms explaining the effects of increased macro-diversity on individual outcomes: perception of threat versus intergroup contact. Moreover, we discuss individual and contextual moderators of the relation between ethnic diversity and intergroup attitudes. Finally, we end this chapter by outlining future directions for research.