Game theory and evolution to explain cooperation!

I could never imagine that guppies or naked worm were good at poker! Well, they are not actually, but the Game Theory that explains poker strategies can also make models to understand the behavior of a guppy facing a predator. There is a lot about the Game Theory that can be explored in Biology, and particularly evolution. One topic that I found very interesting to look at was cooperation.

The model used in the article to illustrate how people tend to cooperate and be fair in everyday trading is quite simple to understand.

Two people are given $100 to split. They cannot see each other and one person is in charge to propose how the money should be split. The other one either refuses or accepts the proposition, and in any case the game stops there. Game theorist would predict that the person splitting the money would go for a very rational and selfish choice, thus proposing a very low percentage. Even though the chances for the proposition to be refused are high, logic suggests that the other player would take it anyway because it is better than nothing at all. However, in real life, this scenario rarely happens. People tend to be more generous and agree to give close to 50% of the money.

The article also proposes an explanation to this behavior: evolution. In fact people believe that only accepting a “fair” amount will lower the chances of being offered too little at the next occasion. Similarly, refusing small amounts increases their chances of being offered a ‘fair’ amount at the next occasion. The variations of this game were tested and the reactions of people seemed to match this evolutionary perspective. For instance when players were allowed to give each other penalties in a game of 4 people, the group that gave the most penalties was usually the one that survived the most to famine, wars and others threats simulations because the players regulated each other more.

The game theory is a fascinating topic!

Source: 

The economics of fair play.

Karl Sigmund,Ernst Fehr and Martin Nowak,

Scientific American, 2001.