In the 1990s, psychologists at the University of California, Los Angeles, developed a scientific theory to account for all the prejudice and violence in the world. Social dominance theory, which attributes sexism and racism (among other isms) to the way humanity organises its social structures, can be used to explain everything from opposition to welfare policies to why we go to war.

Put simply, the theory states that people with power will always seek more of the desirable things in life (as they see it) at the expense of their subordinates.

Today, researchers are applying social dominance theory to try to understand an even broader scope of behaviours. Two recent studies relate people’s views on social equality to how they think and act on environmental issues such as climate change and conservation. The findings hint at radical new ways to increase support for measures that will make the planet more sustainable for all who live on it.

The horrors of hierarchies

Social dominance theory revolves around the observation that most modern human social systems are organised in a similar way (with notable exceptions among the Indigenous communities of the world).

“Human social systems have a tendency to be organised as group-based hierarchies with one small group at the top of the social system and a variety of groups at the bottom,” says Harvard University professor Jim Sidanius, one of the researchers who came up with the theory. “The primary forms of discrimination and anti-group violence we observe around the world and throughout history are simply manifestations of this general tendency for humans to form hierarchical social organisations.”

Sidanius and his colleague Felicia Pratto, now at the University of Connecticut, designed a scoring system known as social dominance orientation (SDO) – a measure of how much people will accept social inequality. It’s based on agreement or disagreement with a series of written statements such as “some groups of people are simply inferior to other groups”.

While it’s not hard to imagine that someone’s SDO score might predict their propensity for racism (which it does), it’s less clear how it would relate to their concern for the environment. But it’s this scoring system that is now being adopted by environmental researchers for exactly that reason.

One recent paper published in Social Psychological and Personality Science brings together data from 25 countries in the first large-scale study of the association between social dominance and environmental behaviours. The researchers surveyed 5,400 participants, determining their SDO score and asking them questions about their environmental “intentions”, such as whether they would sign a petition in support of protecting the environment, or try to reduce their carbon footprint by cycling or walking instead of driving. Their conclusion: that a high SDO score – in other words, being accepting of social inequality – makes a person less likely to take pro-environmental actions.

One recent study looked at the links between social inequality and the economic value placed on the natural environment. Photograph: Wild Taiga/EPA

So how do these two quite different sets of values relate to each other? Lead author Taciano Milfont, an environmental psychologist at the Victoria University of Wellington, New Zealand, says it’s not exactly clear:

“On the one hand, people who hold altruistic values, who want to achieve equality in society, tend to be more pro-environmental. On the other hand, people who are focused more on self-enhancing values and social dominance tend to be less concerned about the environment. This is the descriptive finding and it’s quite robust, but we don’t know yet why it’s the case.”

In fact, one of the original studies on social dominance, led by Pratto and Sidanius in 1994, also considered people’s environmental attitudes – albeit in a much smaller survey of 255 people, who were asked about environmental policies. Given the similar skew of the results, the new findings are not surprising to Sidanius, who says they fit with the notion that social dominance measures a short- and medium-term desire “to gather as much social power and resources as possible”, with little concern for the long-term consequences.

However, the Wellington team didn’t just look at the link between social and environmental attitudes at the individual level. They looked at between-country differences as well, to see if the nature of a particular society has an effect on attitudes. The results showed the relationship between social and environmental attitudes is stronger in countries that are more developed, have less social inequality, and where there is a focus on addressing environmental issues.

A second study, published earlier this year, probed the links between social inequality and the economic value we place on the natural environment. Putting a price on the pollination of crops by bees, or on bears as a tourist attraction, may sound like a dubious concept, but expressing the benefits of nature and biodiversity in monetary terms is now a common goal of environmental research.

The authors (from the universities of Freiburg, Kiel and Berlin) used “willingness-to-pay” for environmental benefits (“goods”) to understand how people valued nature across 22 countries. As a measure of social inequality, they looked at how income was distributed in those countries. And once again, they found that in more unequal societies, people placed less value on the natural environment.

Breaking the cycle

Sidanius, meanwhile, is using his social dominance theory to better understand the toxic divisions that have opened up in American society over recent times.



In May, he published a paper which showed, among other things, that the individual SDO scores of white Americans across 30 states could account for much of the racism, sexism and persecution of immigrants within society – and that, more broadly, the views and behaviours of individuals within societies act to reinforce the hierarchies and inequalities that already exist.

This headline conclusion doesn’t make for pleasant reading: namely, the more hierarchical a country’s society, the more its people act to maintain the social status quo even if it is profoundly unfair, often by employing violence and prejudice towards others.

Psychologically speaking, Sidanius observes that it’s “in their interests” to do so – since when there is a disproportionate amount of power, wealth and influence in a society, the dominant group lives longer and has healthier children, besides countless other benefits (relative to subordinate groups in that society).

So while moving to a more equal society would benefit a much greater number of people overall, Sidanius’s findings underline how hard it is to break the “inequality cycle”, because preventing discriminatory behaviour means changing very deeply ingrained views in a society.

A US study looked at rebranding pro-environmental actions such as recycling as ‘preserving the American way of life’. Photograph: Kathy deWitt/Alamy

Where does this leave us? “The first important step is recognising how the process works,” according to Sidanius. “We can’t be naive about the ease with which these social patterns can be changed or manipulated, but we have to understand the laws of social systems – that is to say, the scientific ‘laws’ – before we can address them.”



He adds that Marxism failed as an ideology because it was based on wrong assumptions about human nature (by some accounts, it assumes people are motivated by benefits for society at large – the common good – rather than their own self-interest).

In terms of the environment, as new research deepens our understanding of the “laws of social systems”, so new ideas emerge for manipulating human behaviour towards outcomes that offer a more sustainable future for the planet.

Milfont, for instance, sees potential for re-framing environmental messages to suit socially dominant groups. “The negative impacts on environmentalism could be eliminated by encouraging people to regard pro-environmental actions as patriotic or consistent with protecting the status quo,” he suggests. One US study from 2010 found success with an approach that presented pro-environmental behaviours as “preserving the American way of life”.

Milfont is quick to point out that due to differing social systems, US studies don’t necessarily translate to a European context. But these studies do suggest that for every country, culture or social set, there may be an alternative way to encourage people to recycle or ride their bikes more – one which, in a highly pragmatic way, appeals to the prevalent social attitudes, not just environmental ideals.