New research paper about cooperation in groups of Saami reindeer herders

People rely on one another in fundamental ways, but cooperation in groups can be fragile. Every day, we face tensions between acting in a socially responsible manner and following our own self-interest. These situations are called social dilemmas and they come in varying shades of subtlety, from littering and eBay to overpopulation and climate change. Overcoming these dilemmas can make all the difference, especially for marginalised groups such as pastoralists – people who make their living from herding animals.

Pastoralists use about a quarter of the world’s land for grazing their herds. Nowadays, all over the world, governments are privatising many of their pastures, and so herders must work together in increasingly fragmented places.

We wanted to learn how groups of Saami reindeer herders living in Norway’s Arctic Circle worked together. Our study, just published in the journal Human Ecology, found that cooperation pivoted around the ‘siida’: a group of herders—often family members—sharing pastures and migration routes. Smaller siidas were more cooperative, but the presence of closer family members did not affect cooperation.

While interviewing the reindeer herders, we gave them vouchers for five litres of petrol and asked how much of it they wanted to contribute to their siida. The amount they’d receive in return depended not only on how much they chose to give but also on how much everyone else in their group gave.

This economic situation is known as a public goods game. A public good is any resource (or ‘good’) that’s open for anyone to access without diminishing through use. This blog post, for example, is a public good. Your enjoyment (or otherwise) of it doesn’t stop anyone else from reading.

In a public goods game, a group of people choose how much of their money to share with everybody else. The experimenters increase whatever was donated to the group’s pot (we multiplied donations by 50 percent) and then distribute the final amount equally among all players, regardless of how much each person contributed.

This kind of experiment is very much a caricature of real-life dilemmas about how best to make decisions given how other people are behaving, but caricatures are helpful shortcuts to understanding cooperation – especially in places like Norway where everything costs a lot of money and learning how reindeer herders work together out in the pastures would require decades of observation (and a hardiness to the despair of winter that I probably can’t muster).

In theory, people make their donation decisions based on how much they expect to get back. In economic parlance, this is the ‘marginal per-capita return rate’. Groups with fewer members tend to have higher return rates and so they should donate more. This is what we found:

Petrol donations by marginal per-capita return rate

Smaller groups could expect to receive more in return for every litre they donated and this corresponded with larger donations in our experiments.

We also asked people about how often they took part in a set of activities – tasks like herding, slaughtering and making handcrafts (duodji, in the Northern Saami language). Herders directed most help towards their own siida, though helping people in other siidas wasn’t unknown. This makes sense, since siidas might rely on one another to repair shared fences or to separate reindeer when their herds mix.

Cooperation, as reported by the herders we interviewed

The study is available to read for free here:

For the overtly nerdy, we’ve also released our data and analysis code here:

New research paper about Saami reindeer herders and gift-giving

I’m enormously pleased to say that I have a new bit of research published. The paper is about gift-giving in a group of reindeer herders living in Norway. It’s the culmination of nearly two and a half years’ worth of work – from our initial planning, though some months of hanging out in the (surprisingly warm) arctic, to endless rounds of statistics and writing and revising and statistics and *facepalming* and statistics and *headdesking* and statistics and revising.

The paper itself is published in a journal called Behavioral Ecology but because of funding constraints we weren’t able to make it open access – to my great chagrin (but you can download a PDF for free here or read it online here, or feel free to email me if you want a copy).
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The evolution of cooperation isn’t so puzzling

There’s a bit of a vibe in evolutionary anthropology/biology/theory that the evolution of cooperation is puzzling. A recent book — The Moral Brain — says “cooperation between unrelated individuals poses a puzzle from both the perspective of natural selection and that of rational self-interest”. Still there are loads (and I mean *loads*) of theoretical models showing a variety of ways for cooperation to evolve. In a moment of heightened procrastination, I decided to delve into the literature and find out just how puzzling scientists find cooperation (warning: this is not even remotely a scholarly piece of work).
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The hidden joy of giving — anonymous donations may be good for group stability

Why give to charity? Rarely a day goes by without fresh fundraising appeals flooding our inboxes, from co-workers running marathons dressed as cartoon characters to distant cousins climbing even more distant mountains. You might contribute for any number of reasons: familial duty, perhaps, or to boost your reputation as a generous person.

Evolutionary explanations of altruism suggest that generosity brings gains in social status or influence. If this were the case, when donating on the open plain of the internet, people would be expected to publicly contribute above the average. But Nichola Raihani of University College London found quite the opposite: the princely as well as the stingy were more likely to donate anonymously.
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