Trust, markets, and cultural changes in Tanzania
Trust is central to people’s social lives because we are constantly sharing advice with each other. No one person ever thrives alone, so we rely on other people’s knowledge to inform our decision-making.
People are bombarded by all kinds of social advice. Whether it’s on social media or with family and friends, you’re liable to hear which foods you should eat, which trends you should notice, or which shops you should avoid.
And yet, relying on another person’s advice carries a risk of misinformation. The person sharing advice with me might be dishonest, or perhaps they are simply mistaken. The problem we are constantly needing to solve, then, is: how should people decide whether or not someone’s advice is trustworthy?
A recent paper in Evolutionary Human Sciences that I wrote with Ed Hagen tackles this question. It was based on my fieldwork in Tanzania, where I surveyed Maasai cattle herders who know the value of useful, trustworthy advice.
Herding cattle and the importance of sharing advice
For Maasai herders, the most important and respectable thing you can have in life is a lot of healthy cows. Maasai have been herding in East Africa for centuries, and their diets have traditionally included large amounts of milk, meat, and blood from their cattle.
A key challenge for Maasai (and many other East African herders) is finding available grass, because the rain seasons are short, erratic, and punctuated by long, hot droughts. Maasai have traditionally dealt with this challenge by constantly moving their herds around, but this strategy is much harder today than it used to be. Cities, towns, farms, roads, and national parks are all expanding, competing for land that can no longer be used for herding. In other words, more private property means fewer options for grazing.
It’s critical for Maasai herders to carefully plan out where they will take their cows every day, because moving a herd to a new location costs a lot of precious calories. Doing so will (hopefully) pay off when a herder finds grass for their cows to graze on, but this isn’t guaranteed. Herders manage this risk, in part, by “eating the news” – a Maasai phrase (anya lomon) that basically refers to regularly catching up with family and friends.
When herders eat the news, they often share information about grazing conditions, which they can use, in turn, to make knowledgeable decisions about their next moves. And yet, more conflict over scarce land availability means that people have a higher incentive to share misleading advice.
When to trust, and when to be skeptical
So then what might explain why people do trust each other’s advice about herding? One possibility is prestige bias, meaning that people tend to put more weight on advice from someone with higher social standing. If we’re left to our own devices it can be hard to assess how knowledgeable people are, but the community’s pooled opinion can be a pretty reliable cue.
Another possibility is that people are sensitive to misinformation risks, so whether or not they trust someone’s advice is based on whether or not they can afford to take a risk. Herders who also farm, for example, might have crops to fall back on if they receive bad advice about herding.
We tested these ideas in an experiment and found that people seemed to be trusting based on whether or not they could afford the risk, and whether or not the source of advice was prestigious didn’t really seem to have an effect on how people judged the advice’s trustworthiness.
I break these results down a little more in this Twitter thread:
New paper in @Journal_EHS with @ed_hagen: Acculturation and market integration are associated with greater trust among Tanzanian Maasai pastoralists.
— Aaron Lightner (@adlightner) March 12, 2021
Paper link: https://t.co/Z6y5HqSDFr
Here's a thread about it /1
Our exploratory analysis was where we saw the really interesting results. We collected a lot of questionnaire data about things ranging from moral values and religious practices, to material wealth and number of wives. When we reduced these many different variables into a few interpretable “components”, we saw a clear pattern in people’s responses.
In some cases, people’s beliefs adhered more to traditional Maasai ideals and their livelihoods were more focused on herding. In other cases, their beliefs were more influenced by Christianity, and their livelihoods were more plugged into the local cash markets.
This pattern wasn’t randomly distributed across the landscape: People on the more “traditional” end of the spectrum usually lived north of a mountain that cuts through the region, making it difficult to access the nearby town. In contrast, people on the more “market integrated” end usually lived south of the mountain, where access to town was much easier.
When we looked at how these response patterns related to whether or not people were willing to trust someone’s livestock advice, we found that the people on the traditional end tended to be less trusting, and the people on the market integrated end tended to be more trusting.
Why did we find this? We don’t know because the analysis was post-hoc and exploratory, but we can make a few testable hypotheses. It could be expanding markets favor more trusting cultural norms, for example, because trust is necessary to make frequent, mutually beneficial trades with strangers.
We speculate about this and more in the article, so if you want to see more, give it a read and have a look at the data and R code on Github.
If you’re interested in learning more about the Maasai people we worked with, check out their NGO working to improve education for Maasai women and children, led by Musa Kamaika, a Maasai elder who has been a wonderful friend and collaborator to us.