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In the short term, humans react negatively to changes in religious diversity, experiencing a dip in quality of life.

A new study from the University of Birmingham and the University of Oxford has found that while changes to religious diversity may lead to a short-term decrease in quality of life for communities, this is reversed in the long term as societies adjust to multiculturalism.

In this study, funded by the Nuffield Foundation, the authors conducted the most in-depth analysis to date of religious diversity and its effects on societal wellbeing. The analysis comprised survey data from more than 100 countries collected over 22 years and finds that:

  • In the short term, humans react negatively to changes in religious diversity, experiencing a dip in quality of life.
  • However, humans adapt to changes in society over time and begin to reap the benefits of diversity, with quality of life returning to normal levels.
  • Negative effects of diversity are mitigated due to the positive effect of increased mixing between different groups.
  • The negative effects of religious diversity dissipate within four to eight years, because they are cancelled out by the positive effect of mixing between different groups.

As demographics have changed because of increasing globalisation, societies around the world are transforming from religiously homogeneous groups to increasingly diverse communities. Researchers have performed the most thorough analysis to date on the effect of religious diversity on human wellbeing, uncovering a transformation process common to countries around the world. The report is published in PNAS.

“Our findings demonstrate that, in the short term, we are inclined to react negatively to changes to religious diversity in our societies,” says study co-author Dr Matthew Bennett, from the Department of Social Policy, Sociology, and Criminology at the University of Birmingham. “However, as society begins to reap the benefits of diversity, and trust between different groups grows, this negative effect on wellbeing disappears.”

Humans have evolved to react negatively to threats to homogeneity, as our survival was dependent on cooperation and cohesion with those belonging to our ‘in-group’, protecting each other from potential dangers presented by unknown others in the ‘out-group’.

Study co-author Dr. Miguel Ramos from Department of Experimental Psychology at the University of Oxford says: “In the short term, changes in diversity may have a negative effect, such as a reduction in trust of our neighbours, and of out-groups in general. But in the longer term, over a few years, we can see how societies and their respective groups come to terms with new demographic challenges.

“By focusing only on the short term, we draw an inaccurate, pessimistic conclusion about the impact of diversity. An increase in diversity offers the opportunity for members of different groups to engage in intergroup contact, to get to know each other, and to cooperate. When this occurs, this positive contact-increasing effect of diversity trumps the negative, trust-decreasing effect of diversity.”

Dr. Ramos adds: “Previous studies have lacked or not exploited data with the longer-term perspective analysed here, and it is crucial to see intergroup relations – whether conflict or cooperation – not in static terms, but in dynamic terms.”

While humans may initially reject diversity as a safety mechanism, they also have an impulse to engage in contact with other people and groups. Biologists and anthropologists have long believed that humans fared better than other species due to contact with ‘unknown others’, bringing about a variety of benefits that cannot be attained by ‘in-group’ interactions alone. Examples include increased genetic diversity owing to intergroup mating, the sharing of knowledge and information, and access to new resources.

“Over time, humans adjust to diverse societies. We see trust increase, and as the positive benefits of religiously diverse societies materialise, quality of life improves back to expected levels,” says Dr Bennett. “Our research found this can take around four to eight years. This can be speeded up to the shorter end of the scale through favourable integration policies for immigrants, for example.”

Data and method

The data comes from multiple waves of the World Values Survey, the European Social Survey and the Latino Barometro, representing over 100 countries measured over 22 years. Each contained comparable measures of happiness, life satisfaction and health, combined to form a quality of life index. Religious diversity was measured via the Herfindahl index.

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The paper ‘Humans adapt to social diversity over time’ is published in PNAS 

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