From a biological perspective, the biggest mystery of modern life is why people in modern societies want small families or no family at all. Why has this change happened over a century and what does it tell us about the way humans adapt to change?

How industrial revolutions lead to cultural revolutions

Research by the University of Exeter (UK) and University of California Davis (US) suggests why our ideas about sex, marriage and parenting have changed so much over the last century.

The study presents a new theory for why cultures transform as countries develop economically and particularly why individual success becomes more desirable than having a large family.

The research was presented by Dr Lesley Newson of the University of Exeter in a talk entitled ‘Explaining the Mystery of Modern Life’ at the BA Festival of Science on Tuesday 9 September.

The research team developed a mathematical model to look at how the social upheaval wrought by industrialisation affects attitudes and behaviour. Social scientists have long accepted that industrialization changes people’s attitudes about the family and life’s priorities. But what the model shows is that this change is likely to take many generations to play out. If this is the case, the rapid changes that Western societies are experiencing now could be the continuing effect of the social change that occurred several generations ago. If so, it explains why policy-makers have had little or no success in their attempts to make families less fragile and increase respect for authority.

To test their model, the team compared data on socio-economic factors and cross cultural studies of attitudes in countries that had begun to develop at different times in the last two centuries. “Our model predicts that countries all over the world will follow the same pattern of cultural change,” explains Dr Newson of the University of Exeter’s School of Psychology. “We found that cultural differences between countries are closely linked to their position on the progression that begins with economic development. Countries, such as China and India, which began to develop more recently, are proceeding along the same trajectory as countries like the UK, which began to develop in the 18th and 19th century.”

Most explanations for modern attitudes and the way they change concentrate on economic factors. However Dr Newson sees culture as something that evolves in a similar way to the evolution of genes. She says: “The changes we have experienced are part of a cultural evolutionary process that is triggered by economic development. But changes in people’s financial circumstances may not be the main trigger of cultural change. Following economic development there is a profound change in the structure of communities and this changes the nature of the social information people receive. As communities change, people no longer receive most of their social information from face-to-face interaction with their friends, neighbours and family. They begin to receive social information from a much wider network, in a variety of ways and via the mass media. This is much more plausible a trigger of cultural change.”

The researchers argue that since less of the information is from family, it will be less encouraging of "family values" – the need to provide help to relatives, to respect elders and to produce the next generation to carry on the family name. They believe that this causes beliefs and values to gradually evolve in predictable directions.

The data provide support for this view. The populations of countries like Estonia and Latvia, which began to develop at about the same time as Britain, have many of the same ideas about sex and marriage as Britons do, even though they are much less wealthy. Meanwhile, much wealthier nations which developed more recently have values that are closer to those of traditional communities.

In her talk at the BA Festival Dr Newson argued that an important key to understanding the modern changes is something that happens shortly after a society begins to develop - couples no longer want so many children. “As a member of modern culture, I believe that limiting family size is a good idea” Dr Newson says. “But, as a biologist, I find it extremely puzzling that people believe this. According Darwinian theory, producing offspring is the purpose of life. All animals and plants behave as if it is the purpose of life and, until very recently in human history, people did too.”

The research has implications for international relations. One of the conclusions from the research is that many of the cultural differences between countries might be the result of the countries being at different points on this cultural evolutionary progression. Dr Newson says: “Western politicians get frustrated that developing countries do not immediately embrace their country's ideas of democracy and human rights, but they forget that cultural change takes time. It took Western countries many years to evolve their current beliefs and values.”

Photograph above courtesy of Benjamin Dudoit.

Date: 9 September 2008

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