Gambling our way against climate change

So far, no number of global summits has achieved a sustained reduction in green-house gas emissions. To study how representatives act in this dilemma, the scientists played a game with volunteers divided into groups or "countries." Together, the countries need to raise a set sum of money by contributing from their pots. For each country, a representative decides how much money to contribute. If all countries together manage to raise the required target amount at the end of the game, the participants can keep the remaining money in their country's pot. However, if the countries fail to reach the target sum, participants lose all remaining money. Similar to real-life countries, the representatives in this game are up for election after several rounds.

In the experiment, selfish representatives, who contribute less than their country's fair share, get preferentially re-elected. But why do "subjects" re-elect representatives who mainly pursue the country's success, while ignoring the risk of losing collectively? Hilbe and colleagues show that selfish representatives are extortionists: They get the representatives of other countries to compensate for what they themselves do not contribute. All countries together -- on average -- reach the target amount of money, but the extortionate country maximizes its own pot.

This study suggests a compelling answer to the question of why we keep electing representatives who- apparently -- do not contribute enough to reaching global goals. As representatives get preferentially re-elected if they act selfishly, they act selfishly. But at the same time, selfish representatives are extortionists, as they successfully persuade others to contribute more towards the global goal. In the end, the collective goal is reached -- it is to be hoped.