Who We Are: Part II

Social Networks and Obesity

This is the second part of a series of postings in which I explore the growing mountain of scientific evidence that supports that human have, as a species, a cooperative nature.



In July of 2007 the New England Journal of Medicine released a study that had followed 12,067 people in the Massachusetts town of Framingham over a fifty year period of time. What they found was astounding. According to the Dallas Morning News, the study "was the first to demonstrate that obesity – and perhaps other health problems that involve behavior or lifestyle – spreads through social networks."

To show how effective social networks are in affecting weight it was found that the chances of becoming obese went up 57% if a friend became obese, 40% if a sibling’s changed, and 37% if the person was a spouse. The most outstanding chance of change was if a close friend’s weight changed. If so then the chances that a person would become obese went up an amazing 171%!

In the study they were able to rule out several factors. First, they found that there was no statistical significance for socioeconomic class or access to healthy food. It turned out that there was a closer connection between friends that lived hundreds of miles away than there were between next door neighbors. In addition, they were able to rule out "birds of a feather" or that obese people were attracted to similarly obese by excluding those friends who were both obese at the start.

So what was taking place? According to a co-author of the study, Nicholas Christakis with the Harvard Medical School, "What we think is going on here is emulation." The behavior of emulation is certainly one trait expected to be found within a cooperative species.

In the third part of this series I’ll explore some of the animal studies and how they support the evolution of a cooperative human species.

Who We Are: Part I

Longevity, Cooperativism and Human Nature



Philosophers have historically taken the three highly simplified views of human nature and have built various models consisting of differing degrees of complexity. Jean Jacques Rousseau believed that we are by nature good and that we are corrupted by society (the “noble savage”). The existentialist philosopher Jean-Paul Sartre held that human nature is neutral, with an individual’s free will being the sole element that decides our actions. According to Sartre as humans we have a radical freedom to the point that we are “condemned to be free.” Others that share his view of neutrality often give control largely to environmental socialization and conditioning (such as B.F. Skinner). Then there was Thomas Hobbes who held that human nature is bad. In Leviathan Hobbes wrote, “So that in the first place, I put for a general inclination of all mankind, a perpetual and restless desire of power after power, that ceaseth only in death.” He thought that any goodness exhibited by someone was the result of society keeping that person’s dark side in check. Otherwise, without society’s restrictions, human existence would be “nasty, short, and brutish.”

There is a growing body of scientific studies that now point towards an understanding that humans have a hardwired predisposition in which working together appears to be intrinsically reinforcing and which in turn encourages future cooperative behavior. Studies show that this drive is so powerful that if someone fails to cooperate then another person will go out of his or her own way to punish the uncooperative one, even at his or her own sacrifice. This revelation of the cooperative nature of humankind is so important that it deserves close examination.

A recent study by Brigham Young, published in the Public Library of Science, found that having social relations can actually increase one’s longevity. They took the results of 148 studies involving 138,000 people and combined them. What they found was a clear statistical trend that indicates that having strong social relations could increase a person’s lifespan in comparison by as much as four years.

What we see in this study is natural selection at work in the evolution of early humans. Those early humans who were by nature cooperative lived longer and therefore had more babies than their less cooperative peers. Over time the cooperative members of our human ancestors became dominant in the species and the “rugged isolationists” became a rarity.

In the next installment I will look at another study which involves social networking that found further support for cooperativism being hardwired within our nature