The dark side of heterogeneous ingroup identities: National identification, perceived threat, and prejudice against immigrants ☆ , ☆☆ Juan M. Falomir-Pichastor ⁎, Natasha S. Frederic University of Geneva, Switzerland HIGHLIGHTS ► We examined the effect of the perceived heterogeneity of national identity on nationals' reactions towards immigrants. ► Heterogeneity increased perceived ingroup threat and prejudice among high, but not low, identifiers. ► These findings suggest that the heterogeneity of ingroup identity may result in negative intergroup relations. abstract article info Article history: Received 20 April 2012 Revised 27 August 2012 Available online 12 September 2012 Keywords: Identity heterogeneity Ingroup threat Prejudice National identity National identification The present research examined the impact of perceived ingroup identity heterogeneity on intergroup relations. We predicted that the effect of a heterogeneous national identity on perceived ingroup threat and prejudice toward immigrants would be moderated by strength of national identification. To test this hypothesis, we conducted two studies (N = 230) in which we evaluated national identification and experimentally manipulated national identity heterogeneity (low versus high), and then assessed perceived ingroup threat and prejudice to- ward immigrants. Study 1 showed that perception of immigrants as a threat increased as national identification increased. Moreover, national identity heterogeneity increased the perceived threat when national identification was high, but not when it was low. Study 2 extended these findings to a measure of prejudice against immigrants from both similar and very different countries. We discuss our findings in terms of the impact heterogeneous so- cial identities may have when there is a perceived threat to the clear and representative definition of the ingroup identity. © 2012 Elsevier Inc. All rights reserved. Introduction Social identities, including national identities, may be perceived as homogeneous or heterogeneous. For instance, a national identity is homogeneous when all nationals share characteristics such as ethnic origin, language, values, and practices within a singular and uniform national identity. Conversely, a national identity is heterogeneous when sub-groups with different characteristics co-exist within a complex, diverse and multicultural national identity. The actual heterogeneity of social identities depends on many factors, but how an identity's heteroge- neity is perceived can also be affected by the extent to which influential actors (e.g., political parties, media) emphasize diversity and differences. Hence, examining how the perceived heterogeneity of an ingroup identi- ty affects intergroup relations is of both theoretical and social relevance. Numerous studies have investigated the effect of the perceived heterogeneity of overarching identities associated with complex and inclusive groups (e.g., multicultural societies) on attitudes toward sub- groups within a superordinate category (e.g., Crisp, Turner, & Hewstone, 2010; Deschamps & Doise, 1978; Steffens, Reese, Ehrke, & Jonas, in preparation; Waldzus & Mummendey, 2004). However, there has been relatively little research into the effect of ingroup identity heterogeneity on attitudes toward outgroups that do not belong to the superordinate category and that do not contribute to this heterogeneity (see Roccas & Amit, 2011). The present research was designed to help fill this gap by examining whether the perceived cultural heterogeneity of an ingroup identity (Swiss national identity) influences the perception of out- groups (immigrants) as threatening. More specifically, we investigated whether national identification moderates the effect of identity hetero- geneity on perceived ingroup threat and outgroup prejudice. Heterogeneity of ingroup identity and intergroup relations Social psychology research has led to two conflicting views of the effect ingroup identity heterogeneity has on intergroup relations. Some fields of research suggest that ingroup heterogeneity can lead to more positive intergroup relations because heterogeneity tends Journal of Experimental Social Psychology 49 (2013) 72–79 ☆ This article is dedicated to the memory of Fabrice Terzi. We are grateful to Emmanuel Nobile for his help in collecting data. We are also indebted to Kai J. Jonas for his comments on an earlier version of the manuscript. ☆☆ This research was partly supported by the Swiss National Science Foundation (no. 100011‐100283). ⁎ Corresponding author at: Social Psychology (FPSE), University of Geneva, Bd. du Pont d'Arve, 40, CH-1205 Geneva, Switzerland. E-mail address: Juan.Falomir@unige.ch (J.M. Falomir-Pichastor). 0022-1031/$ – see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jesp.2012.08.016 Contents lists available at SciVerse ScienceDirect Journal of Experimental Social Psychology journal homepage: www.elsevier.com/locate/jesp