Generous Players: Game Theory Explores the Golden Rule's Place in Biology

By Klarreich, Erica | Science News, July 24, 2004 | Go to article overview

Generous Players: Game Theory Explores the Golden Rule's Place in Biology


Klarreich, Erica, Science News


Charles Darwin's theory of natural selection seems to describe a brutal world in which creatures compete ruthlessly to promote their own survival. Yet biologists observe that animals and even lower organisms often behave altruistically. A vervet monkey who spots a leopard, for instance, warns his fellow monkeys, even though the call may attract the leopard's attention to the individual. A vampire bat that has hunted successfully shares nourishing blood with a fellow bat that failed to find prey.

Such behavior is obviously beneficial for the species as a whole. However, natural selection postulates that successful organisms act to propagate their own genes. If selfish animals can take advantage of more-generous peers, how has any generous behavior survived the mill of natural selection? Darwin himself pondered this puzzle. Focusing on human evolution, he wrote in 1871 that "he who was ready to sacrifice his life, ... rather than betray his comrades, would often leave no offspring to inherit his noble nature."

Somehow, the altruistic behaviors observed in the wild must benefit the giver as well as the receiver. However, pinpointing how this works in animal populations is a huge challenge. In most cases, it's impossible to measure precisely how an animal's cooperative behavior affects its chances for survival and reproduction.

Now, theoretical research is starting to fill in the picture of how cooperation may survive natural selection. Some of the most illuminating ideas are coming from game theory, the field of mathematics that studies strategic behavior in competitive situations.

For decades, game theorists' basic paradigm for the puzzle of cooperation has been the scenario called the prisoner's dilemma, in which each player has a powerful incentive to exploit the other. The game is set up so that cooperation is best for the group, but each player individually does better by taking advantage of the other. A growing body of mathematical analysis and computer modeling now suggests that in many circumstances, cooperators can survive in the prisoner's dilemma. In the April 8 Nature, researchers argue that, under certain conditions, a cooperator can infiltrate, and eventually take over, a population of cheaters.

Meanwhile, other game theorists are arguing that the prisoner's dilemma isn't the be-all and end-all of cooperation test beds. In the same issue of Nature, researchers highlight another set of interactions, called the snowdrift game, in which players have incentives both to cooperate and to exploit each other. The new analysis of the snowdrift game challenges some accepted wisdom about which environmental factors encourage cooperative or exploitative behavior.

SELFISH STRATEGIES In the prisoner's dilemma, the police are separately interrogating two accomplices. Each criminal has two options: to cooperate with the other by keeping quiet or to defect by squealing on the other. If both cooperate, they'll each receive a 1-year sentence. If each incriminates the other, they'll both get 5 years. But if one cooperates and the other squeals, the cooperator will land a 10-year sentence, while the squealer will get off with only 6 months in jail.

Chase through the options, and you'll find that no matter what course one prisoner chooses, the other will do better by defecting. So, if the two players are perfectly rational, both will inevitably squeal.

The game neatly encapsulates the cooperation paradox: Even though cooperation is the best plan, it fails to be adopted, since cheating benefits the individual.

Although the prisoner's dilemma scenario may seem artificial, many interactions of animals and other organisms may have a similar structure of rewards and penalties, some biologists and game theorists argue. In biological versions of the prisoner's dilemma, organisms are competing not for shorter prison sentences but for increased fitness and reproductive success. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Generous Players: Game Theory Explores the Golden Rule's Place in Biology
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Author Advanced search

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.