Imagine that your acquaintance, “Don,” isn’t, um…very picky about who he dates. In fact, imagine that it’s a misnomer to say that he “dates” at all. It’s more that he meets a new woman out at the bars every couple of weeks, becomes sexually involved with her for a brief time, and then quickly moves on. A lot of people would say that this acquaintance of yours is a cad (or worse). But here’s a more interesting question: do you think he’s religious? The answer is that you probably don’t. A recent paper in Psychological Science suggests that people view religious believers as more committed and less promiscuous in their romantic relationships, and that this assumption explains why believers are (usually) trusted more than their secular counterparts.
The paper, “Religious People Are Trusted Because They Are Viewed as Slow Life-History Strategists,” presented three studies that explored the relationship between relationship strategies, religiosity, and social trust. But before I get into the details of those studies, let’s talk about an important concept the paper builds on: life history.
Life History Theory
First off, life history doesn’t mean personal narrative biography. In both evolutionary biology and the evolutionary social sciences, “life history” instead refers to the trade-offs that animals and other life forms have to make between different biological goals: specifically, between maintaining their own health, putting effort into reproduction, and – if relevant – caring for offspring.
Both reproduction and survival are important for all life forms. But in the long run reproduction is thought to be more important as far as evolution is concerned, because what evolution cares about – what it can “see” – is only the biological fitness of organisms. So all organisms try to adjust their efforts over the course of their lives to maximize fitness.
Fitness, in turn, just means how many viable offspring an organism with a given phenotype leaves behind for the next generation. So, for example, a wolf that doesn’t leave a single pup behind has been extinguished from the evolutionary lineage. But a wolf that leaves behind 50 descendants, each of whom has pups of its own, has hit the evolutionary jackpot. Because it’s fitness, not survival, that evolution rewards, most living things will choose to sacrifice their own well-being for the chance to reproduce. But when they’ll make that sacrifice – and in what circumstances – is a matter of strategy. Some species or individuals will always drop everything to mate, even if it means they’ll likely get eaten by a predator (or, in the case of some unfortunate spiders, by their own paramours) right afterwards. Others are more cautious, preferring to be more picky about who they get involved with.
Which strategy any given species or individual chooses is partly a function of its environment. When the world is hostile and dangerous, you might even prioritize looking for mates over scrounging for survival. Why? Because you’re not likely to live very long, that’s why. If successful reproduction – not simple survival – is the ultimate biological goal, then you’d better take the chances for mating whenever and wherever they come. That way, you can leave behind lots of offspring, and one or two of them might make it to adulthood.
But if you’re living in a safe, comfortable environment, then it might make more sense to be more picky, to spend more effort on feeding yourself, and to conserve your energy. If you choose this strategy, you can wait for a really high-quality mate to come around, and then focus your efforts on wooing him. Or her. Or it. (Not all species are sexually dimorphic.) You can invest heavily in bringing up the resultant offspring, trying to ensure that they all survive to maturity. This is an example of what evolutionary biologists formerly called a “K” strategy – a long-term, high-investment reproductive strategy that focuses on offspring quality over quantity. By contrast, the first strategy has its priorities the other way around: it emphasizes number of offspring over their quality.
Some researchers, particularly in the social sciences, have come to describe these strategies as “fast” versus “slow.” A fast life history strategy means that you try to maximize reproduction, invest little to no effort in offspring, refrain from long-term commitments, and (probably) die early. A slow life history strategy means investing heavily in offspring, saving your relational investment for committed partners, and planning to live a long time. Another way of putting this is that animals and people with “slow” life history strategies plan for the long term. Those with “fast” life histories live for today.
What does this have to do with religion?
Religion and Life History
The paper’s authors, Jordan W. Moon, Jaimie Arona Krems, and Adam B. Cohen, noted that people tend to trust religious believers more than non-believers. For example, one well-known study found that people across many different cultures implicitly associate atheism with immorality and crime. (Fascinatingly, even atheists held this prejudice.)
At the same time, a growing number of researchers argue that religion – particularly world religions, such as Christianity, Islam, and Hinduism – seem to be associated with slow life history values. For example, these traditions all emphasize long-term relationships, while strongly disapproving of sexual promiscuity. Moreover, research suggests that religious believers tend to be less impulsive and more invested in family than non-believers. People with “slow” life history traits, meanwhile, are also thought to be more cooperative and trustworthy than those with “fast” life histories.
Moon and his co-authors wondered whether the reason why so many people prefer to trust religious believers is simply because they expect believers to exhibit slow life history behaviors: that is, to be relatively self-controlled, less interested in casual sex, and committed to family and in-group relationships. That is, could religious belief simply be a heuristic signifier of slow life history?They tested this hypothesis in three different ways. In the first study, subjects viewed made-up dating profiles that included information about whether the fictitious person profiled was Christian or nonreligious. The study participants then responded to questions about the target of the dating profile, including whether they thought he or she was trustworthy. They also indicated whether they thought the profile target had a committed or uncommitted relationship strategy (for example, by marking their agreement or disagreement with descriptive items such as “Faithful romantic partner”), and whether he or she was impulsive or aggressive.
Results showed that participants viewed religious targets as more trustworthy than their non-religious counterparts. They also thought the religious were more likely to have a “slow” life history strategy. Subjects also viewed religious targets as more educated, less aggressive, less impulsive, and less likely to come from a rough neighborhood.
Importantly, the belief that religious subjects followed a high-commitment relationship strategy was a significant mediator of the relationship between target religiosity and perceived trustworthiness. That is, study participants believed that religious targets were more trustworthy in large part because they expected them to have a slower life history. (Higher levels of imputed education also mediated this relationship.) This indirect effect held for all levels of participant religiosity, meaning that even non-religious participants found religious dating profile targets more trustworthy because of their supposedly committed reproductive strategies.
In a second study, Moon and his colleagues changed things up by directly providing information about the fictitious target’s dating strategies. Study participants were able to see whether profile targets hoped for long-term matches (“My goal is to find that special someone, settle down, and start a family”) or for short-term flings (“I don’t see myself settling down anytime soon, I enjoy playing the field…”). They were also given information about the target’s self-professed religiosity.
In the results, targets who hoped for committed relationships were considered much more trustworthy than targets who wanted short-term flings. Committed targets were also considered less impulsive, less opportunistic, and more educated than those who seemed avoidant of commitment. Importantly, the religiosity of the dating profile targets had little effect in these analyses. Profile religiosity wasn’t directly associated with perceived trustworthiness, and its negative relationship with perceived impulsivity, though significant, was small. In other words, when information was directly available about potential dates’ life history strategies, their religious commitments were no longer as interesting for the research participants.
In a final study, participants viewed three different dating profiles: one nonreligious, one Christian, and one Muslim. Participants received no direct information about the profile targets’ dating strategies. Again, targets who were religious were perceived as more trustworthy than nonreligious targets. (This effect was weaker for Muslim targets, but still significant). Religious targets were once again viewed as having significantly slower or more committed mating strategies than the non-religious, and this relationship significantly mediated the effect of target religiosity on perceived trust.
In other words, even members of a non-majority religion (these studies were carried out in the U.S.) were still viewed as more trustworthy than the nonreligious, largely because they were perceived as having a long-term relationship strategy. Perhaps most interestingly, while the religiosity of the participants themselves significantly moderated the perceived trustworthiness of Christian targets, it had no effect on the perceived trustworthiness or life-history strategy of Muslims.
Life History and Science
Humans are animals. We might be more than that too, but we’re still animals. This means that we face the same motivations and challenges that other animals do in life – including how to invest our limited time and energy when it comes to finding mates, starting families, and taking care of ourselves. Moon et al.’s findings suggest that religiosity is seen as a heuristic indicator of a particular type of life strategy: one that emphasizes long-term romantic attachments over short-term ones, discourages promiscuity, and encourages impulse control.
In turn, these “slow” behaviors incite trust in others – possibly for unrelated reasons. Namely, people who follow a committed relationship strategy, who are non-impulsive, and who are non-opportunistic are seen as less likely to take advantage of others (regardless whether religious people actually have these traits or not). As a result, religious believers may enjoy higher levels of general trust in large part because people assume that their religiosity indicates that they follow committed relationship strategies. In the authors’ words,
our data suggest that perceivers are perhaps less concerned with targets’ specific beliefs, and more interested in the likely behavior they can infer from religious information…Indeed, our results suggest that simply knowing someone’s reproductive strategy was sufficient to diminish drastically the effect of religion.
While these findings are fascinating, the paper’s nomenclature may generate some confusion. Specifically, the term “life history” has come to mean something quite different in the social and human sciences than it does in biology. Biologists use “life history” to describe a whole range of possible tradeoffs: for example, between body size, number of offspring, and longevity among, say, two species of island birds. This more formal version life history theory is inextricable from population biology and even ecology. Moreover, it isn’t usually used to study individual differences – instead, biologists use it to explain key differences between species or populations.
But in the human behavioral and social sciences, researchers often refer to “life history” specifically in relation to psychological and personality traits, and particularly to the trade-off that individuals make between committed and non-committed relationship strategies. As one recent paper found, the very concept of “life history” has therefore undergone conceptual drift as it migrated out of evolutionary biology and into the social sciences. It may be that what Moon and his co-authors in this paper were describing as “life history” is actually better described as a “pace of life” tradeoff, which is distinct from (though related to) formal life history.
This loss of fidelity in scholarly transmission may illustrate some dangers of cross-disciplinary research and collaboration, but Moon et al.’s paper also showcases its exciting opportunities. Insights from biology have helped spawn an entire way of looking at human behavior and psychology. Work is needed to conceptually unify the social and biological versions of life history theory, but in the meantime, we’re learning some important things.
Such as why we don’t trust guys like Don.