Perceived Vulnerability to Disease and Ideology-1 RUNNING HEAD: Perceived Vulnerability to Disease and Ideology Infection and Ideology: Perceived Vulnerability to Disease Predicts Political Conservatism

Recent research on the behavioral immune system suggests that perceived vulnerability to disease is associated with greater ingroup preference, conformity, and support for established cultural practices. However, little of this research has looked at the implications of perceived vulnerability to disease for an orientation linked to many of the above outcomes: ideology. In two studies, we test the hypothesis that perceived vulnerability to disease should be associated with greater political conservatism. In Study 1, we find a relationship between perceived vulnerability to disease and increases in conservatism over time. In Study 2, we use data from the World Values Survey to demonstrate that perceived vulnerability to disease predicts a stronger preference for the political right in a large sample of respondents from a wide variety of nations. Together, these results suggest that the consequences of the behavioral immune system may extend to abstract identifications like ideology. Perceived Vulnerability to Disease and Ideology 3 Evolutionary approaches to social and political psychology suggest that various psychological mechanisms developed in response to the adaptive challenges humans encountered in the ancestral environment (Cosmides & Tooby, 2013). In particular, the adaptive utility of avoiding pathogens and infectious disease may have been especially important for reproductive fitness over the course of human history, and recent evidence reveals the presence of a “behavioral immune system” aiding this goal (Schaller, Park, & Faulkner, 2003). For example, much research suggests that people negatively evaluate and avoid individuals with physical characteristics indicating illness and individuals from unfamiliar outgroups likely to carry pathogens they lack immunity to (Faulkner, Schaller, Park, & Duncan, 2004). Importantly, the extent to which behavior and attitudes are affected by interpersonal, intergroup, and situational cues connoting the threat of disease depends on individual differences in perceived vulnerability to disease (PVD; Duncan, Schaller, & Park, 2009). Building on earlier research dealing with the political implications of objective disease prevalence (Thornhill, Fincher, & Aran, 2009) and disgust sensitivity (Tybur, Merriman, Hooper, McDonald, & Navarrete, 2010), we argue and present evidence that greater perceptions of vulnerability to disease are associated with greater political conservatism. Pathogen Avoidance and the Behavioral Immune System Pathogens constituted a major threat to the survival of human populations throughout history. Indeed, some scholars have estimated that infectious diseases accounted for more loss of human life than all wars, non-infectious diseases, and natural disasters combined (Inhorn & Brown, 1990). In contrast to other threats to human welfare (e.g., intergroup violence), diseasecausing parasites are largely imperceptible, and the origin and means of transmission of disease were largely unknown prior to relatively recent scientific advancements (Murray & Schaller, Perceived Vulnerability to Disease and Ideology 4 2012). As such, traits facilitating the detection and avoidance of infectious pathogens may have conferred evolutionary benefits to humans living in ancestral environments, leading to their retention through natural selection (Schaller et al., 2003). These adaptations are hypersensitive and attuned to general cues that signaled a high risk of infection, and collectively they suggest the existence of a behavioral immune system that evolved as a means to protect individuals and groups against the spread of illness (Schaller & Duncan, 2007; Tybur et al., 2010). Evidence abounds for the operation of this system in response to both the objective presence and the subjective perceptions of infectious threats in one’s environment. At the broadest level, geographical differences in the prevalence of infectious disease can account for cross-cultural variation in a variety of traits and tendencies. For example, assortative sociality, intergroup differentiation, and outgroup avoidance are more likely to be observed in areas with high disease prevalence (Fincher & Thornhill, 2008, 2012). Schaller and Murray (2008) further demonstrated that disease prevalence promotes a cautious personality orientation characterized by lower extraversion and openness to experience as well as more restricted sexual behavior. Finally, “binding” moral intuitions (ingroup/loyalty, authority/respect, and purity/sanctity) that help preserve ingroup cohesion are exhibited to a greater degree than “individualizing” moral intuitions (harm/care and fairness/reciprocity) in countries with higher historical disease prevalence (van Leeuwen, Park, Koenig, & Graham, 2012). Individual differences in the subjective perception of disease threats have similarly been implicated in a broad range of social and political phenomena. For example, members of subjectively foreign social groups, particularly those with unfamiliar hygienic and food preparation customs, may have been more likely to transmit infectious disease than members of one’s own social group in the ancestral environment (Fincher & Thornhill, 2008). Thus, Perceived Vulnerability to Disease and Ideology 5 avoidance of members of such outgroups may have developed as an adaptive response to the threat of disease, particularly during periods of pathogen vulnerability (e.g., Navarette, Fessler, & Eng, 2007). Consistent with this interpretation, individual differences in the tendency to perceive and be wary of disease threats predict avoidant and exclusionary attitudes toward members of outgroups (Faulkner, et al., 2004). In addition, individuals higher in PVD tend to harbor more prejudicial attitudes toward groups bearing physical cues that denote poor health (Welling, Conway, DeBruine, & Jones, 2007). In general, these tendencies encourage adherence to social norms that protect the ingroup and defend the cultural status quo. Indeed, conformity tends to increase when disease is objectively prevalent (Murray, Trudeau, & Schaller, 2011), when the threat of disease is salient (Wu & Chang, 2012), and among individuals chronically high in PVD (Murray & Schaller, 2012). Disease Vulnerability and Political Ideology Thus, survival in the ancestral environment may have been facilitated by the presence of behavioral norms, social attitudes, and cultural practices that promote group-centrism, conformity, and the preservation of established social practices. In turn, we argue that the ensemble of tendencies activated by perceived vulnerability to disease may have implications for a more abstract type of identification: ideological self-placement. Specifically, we argue that PVD should be associated with political conservatism. Current work on the motivational foundations of ideology offers two especially important bases for this prediction. First, many of the immediate behavioral immune system goals activated by PVD align very closely with the values and moral goals associated with political conservatism (e.g., Caprara & Zimbardo, 2004; Jost, Federico, & Napier, 2009; van Hiel & Mervelde, 2004). For example, the group-centrism elicited by PVD shares a natural resonance with the emphasis on ingroup loyalty associated with Perceived Vulnerability to Disease and Ideology 6 conservatism (Graham, Haidt, & Nosek, 2009; Jost et al., 2009). Moreover, the emphasis on conformity and adherence to established norms produced by PVD mirrors the premium conservatism places on social cohesion and the preservation of traditional lifeways and structures (Federico, Fisher, & Deason, 2011; Goren, 2012; Schwartz, 2007; Thorisdottir, Jost, Liviatan & Shrout, 2007). Second, beyond serving these value-based goals, current perspectives on ideology argue that conservatism (like all ideological positions) serves even deeper psychological needs. In particular, Jost, Glaser, Kruglanski, and Sulloway (2003) suggest that political conservatism is motivated by a general need to reduce threat and uncertainty. According to this perspective, conservatism serves these needs by resisting changes to the status quo that produce instability, disorder, and unforeseen harms. Insofar as vulnerability to disease represents a fundamental existential threat, then we should expect it to have the same conservative political implications as other kinds of threats considered by the literature on the psychological bases of ideology (Hibbing, Smith, & Alford, 2014; Jost et al., 2009). In other words, PVD may encourage conservatism not only by directly activating goals that align with the value content of conservatism, but also by heightening a general sense of threat. To our knowledge, prior research has not directly investigated the relationship between PVD and political ideology. However, research generally suggests that a related construct— disgust sensitivity—is associated with conservative social attitudes, identifications, and voting behavior (e.g., Eskine, Kacinik & Prinz, 2011; Inbar, Pizarro, Iyer, & Haidt, 2012; Smith, Oxley, Hibbing, Alford, & Hibbing, 2011; but see Tybur et al., 2010). Of course, while disgust sensitivity and PVD are certainly related, they are distinct. Specifically, disgust can be elicited in response to pathogen cues (Haidt, McCauley, & Rozin, 1994), but also in response to moral and Perceived Vulnerability to Disease and Ideology 7 sexual cues (Tybur, Lieberman, & Griskevicius, 2009). Moreover, disgust is an inadequate representation of perceived disease vulnerability in that it fails to directly tap feelings of subjective infectability (Duncan et al., 2009). Disgust sensitivity measures (e.g., Haidt et al., 1994; Olatunji et al., 2007) also focus on susceptibility to disgust as a general affective response, whereas PVD is conceptualized more specifically as a constellation of personal beliefs about infectability and the negative emotion elicited by perceptions of susc