Evolution Wants Us To Get Along
August 1, 2013

Can’t We All Just Get Along? Evolution Says ‘Yes We Can’

Michael Harper for redOrbit.com - Your Universe Online

The Prisoner's Dilemma questions human morality in a very interesting way. In essence, this hypothetical situation ponders the costs and benefits of individuals acting solely on their own interest versus social cooperation that involves benefits for others. More specifically, this notion suggests people can work together to receive a portion of a reward or betray one another to receive the full reward.

Last year a computer scientist and physics professor wrote a paper which found that, in general, people come out better in the end if they betray their fellow human and make the decision they know will most benefit them. Now, two Michigan State University (MSU) evolutionary biologists are challenging this conclusion.

According to Christoph Adami, professor of microbiology and molecular genetics at MSU, working for your own interests may benefit you in the short term, but in the long run evolution favors those who look out for the good of others.

"We found evolution will punish you if you're selfish and mean," said Adami. "For a short time and against a specific set of opponents, some selfish organisms may come out ahead. But selfishness isn't evolutionarily sustainable."

Adami and co-author Arend Hintze, a molecular and microbiology research associate, have just published their paper in the current issue of Nature Communications.

The report focuses on the Prisoner's Dilemma, a classical dilemma in game theory that has wide applications in a variety of disciplines - from biology and economics to mathematics. The Dilemma has been observed in many areas of life. At one of the most primitive levels, for instance, even fungal cells can't sustain life if they don't join with one another to create large swaths of mold.

When professors William H. Press and Freeman J. Dyson published their paper last year proposing that individuals often do well solely to look out for their best interests, Adami had trouble digesting it.

"The paper caused quite a stir," said Adami. "The main result appeared to be completely new, despite 30 years of intense research in this area."

To prove the previous theory wrong, Adami employed a computer model to understand if choosing a zero determinant (ZD) strategy, where one individual turns on another for a full reward, is sustainable from an evolutionary standpoint. Adami and Hintze created hundreds of thousands of "games" wherein the participants could choose a ZD strategy or work together for the common good.

They found that when these digital participants chose ZD strategies, they generally fared well when playing against participants who cooperated. Yet when two participants both chose a ZD strategy, both ended up on the losing end. And these kind of decisions might not work in the long run from an evolutionary standpoint.

"In an evolutionary setting, with populations of strategies, you need extra information to distinguish each other," said Adami.

So what does this mean? In the end, Adami and Hintze's computer models showed that ZD strategies only work if participants began to learn how the others played the game and adjusted their strategies accordingly.

"The only way ZD strategists could survive would be if they could recognize their opponents," explained Hintze.

"And even if ZD strategists kept winning so that only ZD strategists were left, in the long run they would have to evolve away from being ZD and become more cooperative. So they wouldn't be ZD strategists anymore."

The problem is so compelling, that one clever blogger has even created a free online game to try out Dyson and Press' theory.