Question Your World: Why Are Humans Generous?

Posted: October 3, 2018

Generosity is a vital part of human society. We give blood, we help strangers with directions, we donate to our favorite nonprofits, and sometimes we give advice even if no one asked for it! We do all these things even though they may serve no benefit to us at all. This is just a small example of how humans engage in acts of generosity. But why? Why are humans generous? 

The study of generosity means we need to study psychology, human history, and evolution. This is one of the best parts about science: cross-disciplinary adventures!

In order to study generosity, scientists recently looked at the Hazda population in Africa. The science community is quite aware of these indigenous peoples of Tanzania. We did a report recently on the health benefits of eating like a hunter-gatherer by studying the diet of the Hazda people. Our modern world, as we know it, is still rooted in decisions made by our species about 250,000 years ago. Occasionally we look back to learn how things would have been. To do that, we must consult with the populations that are seemingly cut off from our day-to-day modern world. 

Granted, the individuals that are studied certainly live during our modern times, but they still operate like hunter-gatherers and that helps scientists approximate the way human evolution worked. 

Image credit: Getty Images

The Hazda live their life in a harsh environment where food is scarce. To look into how generosity works in the hunter-gatherer lifestyle, scientists conducted an experiment in which they studied hundreds of adults spread out in a bunch of different camps, which are groups of Hazda individuals living together. This experiment took over six years and involved 400 adults from 56 different camps scattered throughout their territory.

The hunter-gatherer lifestyle involves a few things that are not commonly done in our modern world. They must chase their food, which sometimes takes them far away from their home base. Often there are ceremonies and other cultural activities that also require leaving one's camp and being based out of another camp for a while. So as a part of life, Hazda individuals will find themselves joining different camps every few months or so. 

This experiment involved looking at individual Hazda members and looking at these camps. Each member of the study was given four sticks of honey, a delicious and valuable resource in a landscape where the food supply is unpredictable at best. Later every person involved in the study was asked to put these honey sticks in piles, one for the individual and one for the overall group. While an individual may have varying levels of generosity, there was a pretty remarkable outcome for the collection of honey sticks for the group. By the end of the study, the size of the group pile had tripled! 

Throughout this study, scientists saw that individuals showed different levels of generosity based on local groups and the behavioral norms of the camps. When placed in a generous group, the individuals became more generous also; meaning individuals adapted their own tendencies to match that of the group or camp that they currently occupied. This showed scientists that there was no stable individual tendency and that the individual’s generosity was influenced by the generosity of the camp.

These findings now challenge the existing notion that generosity evolved as a byproduct of individual tendencies to be cooperative or uncooperative. So, regardless of an individual’s leanings toward generosity, a large group that is more generous will pull more generosity out of an individual. This study highlights the flexible nature of human cooperation, which showed that generosity can be contagious

So, the question now is, since we see how it works in a hunter-gatherer setting and can draw parallels to how human evolution helped shape group survival based on generosity, does this apply in modern everyday settings as well? Our modern lifestyle is a pretty far stretch from a hunter-gatherer lifestyle and we certainly see our fair share of both generosity and greed. Could being more generous inspire others to be more generous? A notion worth investigating on many levels …

Naturally, after the research, these scientists published their findings and generously shared it with the world. After all, sharing is caring, folks!