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Subscribe to RSSA video from Emory University's Yerkes National Primate Research Center explains how chimpanzees were tested on their preference for fair outcomes when it comes to sharing goodies.
Primate researchers in Georgia have laid out what they say is the best laboratory evidence yet that chimpanzees have a human-style sense of fairness. Other researchers, however, say the study is flawed — and they're sticking to their view that fairness may be a uniquely human characteristic.
The debate focuses on a key question about human evolution: How long ago did our ancestors acquire what Abraham Lincoln called the "better angels of our nature"? These angelic traits — such as altruism, empathy and fairness — manifest themselves in behaviors that can run counter to our own self-interest.
The latest research, published in the Proceedings of the National Academy of Sciences, argues that a sense of fair play may have arisen millions of years ago, before our ancestors split off from the evolutionary line leading to other primates. The study's principal author, Darby Proctor of Emory University's Yerkes National Primate Research Center in Atlanta, told NBC News that the research "opens up the door for exploring the evolutionary roots of fairness in non-human animals."
"We've concluded that chimpanzees not only get very close to the human sense of fairness, but the animals may actually have exactly the same preferences as our own species," co-author Frans de Waal, director of Emory's Living Links Center, said in a university news release.
However, the Emory group's findings run counter to what other researchers have found in their own experiments over the past few years. One of the researchers behind those earlier studies, Keith Jensen of the University of Manchester, has said "our sense of fairness is a derived trait and may be unique to the human race."
Today, Jensen said he and his colleagues had serious reservations about the latest experiment. "I was excited to see a replication of our ultimatum game studies, seven years on, but was disappointed by the results," he told NBC News in an email.
How the experiment was run
The "ultimatum game" is a key concept in all these studies: The concept refers to an arrangement in which one player makes a proposal to another player to split up a reward. For example, a parent may offer six stickers to a little girl, on the condition that she divides the treasure with her brother. A researcher may offer six banana slices to a chimp, on the condition that it divides the goodies with another chimp.
Emory University
Researchers report that chimpanzees can change their strategy for dividing goodies, based on whether or not the chimps they're sharing with have any say over the deal.
If the shares are totally determined by the little girl, or the first chimp, their offer to the partner tends to be as low as possible. That's what's known as the "dictator game." But if the other partner has the power to veto a deal, it gets more complex. Make too low of an offer, and the partner might reject the proposition out of spite — even though the result is that no one gets a reward. That's the "ultimatum game."
The Georgia researchers ran a variety of games using tokens that could be traded for either equal or unequal shares of stickers (for 20 human children, ranging in age from 2 to 7) and bananas (for six adult chimpanzees). The researchers found that the results of the game were similar for the two groups.
If the one offering the goodies was in full control of the split, that individual kept the lion's share of the goodies. The results were different if the two partners had to agree on the split, however. "Humans typically offer generous portions, such as 50 percent of the reward, to their partners, and that's exactly what we recorded in our study with chimpanzees," Proctor said.
How the debate is playing out
Some questions surround the study: The second partner in the ultimatum game always accepted the offer of a split, whether it was equal or unequal. That applied to the kids as well as the chimps. Such behavior might suggest that the recipients would be happy with whatever they got, and didn't care about the fairness of the deal.
In Jensen's eyes, the fact that none of the chimps turned down an unequal split is a "fatal flaw."
"The ultimatum game hinges on the responder," Jensen said. "If the responder didn't understand the option of refusing, I would simply say the study did not work." Similarly, the children involved in the study may have been too young to understand that they could turn down an unfair deal — something that Proctor and her colleagues admit in their study.
They did report, however, that both the chimps and the children occasionally expressed displeasure about an unequal division. For the kids, it was voiced in complaints such as "You got more than me!" For the chimps, it took the form of spitting water at their selfish partner, or hitting a barrier between their cages.
Proctor and her colleagues cite other studies to back up their claim that chimps are sensitive to unfairness — such as anecdotal, non-experimental reports of chimps negotiating over the division of meat, or leafy branches. But such reports aren't yet rigorous enough to resolve the debate.
Proctor acknowledged that more research will be required to get a firmer grasp on the better angels of a chimpanzee's nature. "We can't be sure what all was going on between the chimps," Proctor said. "That's something we'd really like to explore in the future — how much communication is necessary to convey something to another chimp."
More about the better angels of animal nature:
- How monkeys handle moral outrage
- Sense of fairness goes back to monkeys
- What chimps can teach us
- Dogs can think 'no fair' too
In addition to Proctor and de Waal, the authors of "Chimpanzees Play the Ultimatum Game" include Rebecca Williamson and Sarah Brosnan.
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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Can I infer from this article that greedy people are less evolved than chimps?
Rush Limbaugh does have a certain chimpy look - especially when he's hating on the poor, as Jesus commanded, and the spittle is flying from his fat lips.
Hermit ...... yes you can infer that greedy individuals who believe they have a "right" to what other individuals work for are less evolved than chimps.
Dennis, I didn't know anyone who believes that. That is a twisted interpretation and your own fantasy caricature of progressive thought.
jock..... there is nothing "progressive" about repeating the exact same mistakes as every other form of democracy in recorded history. I will also add that it may not be the go-gooders who feel that way but it for sure is the thought process of those who take advantage of the good intentions of those do-gooders. I have this picture of events after a major riot, stores burned and looted, people injured and even the post office burned to the ground. But come welfare check day there was the line in the ashes and one individual stating "all we want is our money!" excuse me.... whose money? There was an interview with a 3 generation welfare family, the mother never worked, the daughter never worked and the grand-daughter in diapers .... at the end of the interview the daughter was asked if she would like to use this opportunity to thank society for the feeding, shelter, clothing and making possible the survival of her family. Her response was "Well I never thought of it that way". Just how did she think about it (if she ever did)?
So no it is a twisted interpretation nor is it a caricature ... it is just a reality check on what you would like to believe "progressive" means.
" I have this picture of..."
And that's the problem. You have this picture of a caricature "liberal" that is completely unlike any liberal I have ever met. I'm sure you can find people like you describe, but it has nothing to do with the "liberal" worldview.
I believe humans were a Genetic/DNA experiment by Aliens that went wrong and humans turned out to be too aggressive and destructive for them to bother with.
Since right-wing Republicans are closest to apes, that would seem to debunk the finding.
Please don't insult apes by comparing them to Republicans. Apes are Much nicer. They're also not as much into stealing, cheating, and hating. Also peaceful. Apes would not have invaded Iraq.
So right-wing Republicans and left-wing democrats differ how? The end result of either extreme is indistinguishable from the other. The left will deliberately and knowing destroy society and create universal poverty .... except for the small number of elitist at the top laboring so hard doing the thinking determining what is good for the unwashed masses of course.
Sounds like we'll need to hold a chimposyum to discuss the findings in the latest research of "the better angels of a chimpanzee's nature."
Of course chimps have an innate sense of fairness. The real evolutionary question is how did Republicans lose it? Must be a case of devolution.
Religion and Politics are like “two peas in a pod”.
Everything good that happens, ….. either God or the Democrats get the credit.
Everything bad that happens, ….. either the Devil or the Republicans get blamed.
Jim that makes no sense. The devolved primate is the one who refuses to put effort for but thinks they have a "right" to what a fellow primate has worked for. Evolution would favor the primate who understands that effort equals reward but is willing to share what it can with the less successful, but not to the thief or the lazy and not to the point of depriving itself .... You figure out which political agenda I am referring to.
Actually, Dennis, evolution would favor just the opposite. It favors selfishness, with the occassinal bit of cooperation if it is likely ot benefit the individual in the end. In other words, we are very much a product of evolution.
Jock ..... That is exactly the point. Evolution would favor the species who are willing to help fellow group members in hard times and those that refuse to contribute to the whole would die off. The one who did not have a successful hunt today, but did do their part, would get a share in the expectation that the next hunt the one giving may need a share tomorrow. Meanwhile the able bodied individual on the fringe who never hunts or contribute when successful to the whole, but stands in line for his "share" every day will not get a share just because he hangs around. If there were a large number of the group who refuse to hunt or contribute that banded together and stole "their share" from the members who did every hunt how long before the group has enough and either splits off or exiles or kills the thiefs?
What if the able-bodied individuals who did not hunt [or gather, let's not forget that] actually wanted to do so, but were not allowed to because they had not been granted a magic token known as a Job? How long before they band together to kill the individuals who will neither grant them a Job nor permit them to go hunting without one?
Yes, there are deadbeats and moochers in our society - though some of the worst in my opinion are certain members of the rentier class who collect huge incomes while doing nothing to benefit the group as a whole - but there are also a hell of a lot of decent hardworking people who had unemployment thrust upon them, or who are one outsourcing away from that fate. If you have nobody in your family to whom that applies, please enjoy your good *fortune* - because it is almost certainly partly luck and not just your inherent personal superiority that puts you in such an enviable position - and try to have less contempt for those who are less fortunate.
Me thinks some one is confusing the inherited surviva trait of "procreation of the species" ...... with inherited gene mutations that result in an environmentally beneficial "survival of the fittest".
The females especially, of most of the higher species, and many of the lesser species, ...... are well noted for their unselfishness.
The male Seahorse is a contradiction to the above.
Dennis, that sounds like a very liberal way of looking at things.
Although to be clear, evolution does not act for the good of the species
SamC, the male seahorse does not protect the little ones because he is "unselfish." It is because somewhere along the line he lost the evolutionary battle and got stuck with it.
Actually Jock, the male Seahorse is a lot smarter than human males ..... because he doesn't need DNA testing to prove that he is the father of his children.
I wonder what the size of the grant was that supported this socially very important study, in a time of economic difficulty.
Jim
I wonder what the cost of the grant that supported this very socially important study cost the tax payers, in this time of economic difficulty.
Jim
Whatever it was it was a good investment. Understanding the origins and motivation of basic human traits has the potential for unimaginable future benefits. It could very well be (and probably is) that not understanding those traits is what is causing the self-induced economic collapse of the Republic. Why is it every form of demcracy government in recorded history fails for exactly the same reasons? Why is the pattern repeated over and over again? Why is the Republic falling into that pattern with so many recent examples of the economic agenda failures? Understanding why may help a recovery without the cycle of oppression and tyranny that follows the collapse historically before the return of yet another form of democracy.
Except you seem to have let your political biases interpret in in very strange ways, Dennis.
I dont understand .... I have no bias just an understanding from research. The only rational conclusion falls pretty much along the exact same lines as the founders of the Republic. I suggest you start with "The Fedralist Papers" by Hamilton, Madison and Jay. "The Origins of Political Order: From Prehuman Times to the French Revolution" by Francis Fukuyama. Any of the writings of Alexis de Tocqueville. Some of Fredrich Nietzche is worth looking at. These suggestions would be a good starting point, but just that .. starting points.
"If Congress can employ money indefinitely to the general welfare… The powers of Congress would subvert the very foundation, the very nature of the limited government established by the people of America" .Alexander Hamilton
It is not so much a question of "understanding those traits" by those who are responsible for said "self induced economic collapse of the Republic" ..... as it is their nurtured beliefs and greed that they and theirs deserve being "given more for doing less" .... that forces them to not recognize, not accept and/or not admit to the self-destructive nature of their own actions.
For instance, the majority of school teachers, professors and school administrators are constantly demanding high salaries, more benefits and entitlements ….. while averting their eyes and minds to the fact that they are not sending sufficient numbers of their students out into the world with adequate educational resources and talents to become successful “producers” in society for them to earn sufficient revenues for their labor …… that will generate the required tax monies for paying the demands of said school teachers and administrators.
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In actuality, public employees do not pay taxes, they are paid with tax monies and they expend those same tax monies. They are given tax monies to pay for their labors and they give part of that tax money back to pay their taxes.
"The only rational conclusion falls pretty much along the exact same lines as the founders of the Republic."
You had to know you were in trouble right there. If you really think the ONLY way to interpret a chimp sharing bananas is to vindicate the conservative world view, you obviously aren't even aware of your own biases. I could just as easily claim it justifies the equal sharing of ALL resources, regardless of who earned them (which nobody advocates).
I cannot think of ANYTHING more depressing than that we "evolved" from an ancestor species. It insults my intelligence and dignity as a human, created to be separate from all other lower life forms by a God that saw fit to make us a special creation.
Well stop being depressed over something so childish. Take pride in being a member of the primate species and the unique abilities of that species.
God and the tooth fairy are make believe.
Unfortunately we can't make things be not true just because they are depressing.
As opposed to being made from dirt by some deity so we can serve and worship him? now that's depressing. Evolution is just a simple fact!
That's some ego you have there. Time for a reality check I think.
My mom and her siblings had the best method for dividing something while growing up - it was called, "You get to cut and I get to choose."
Rest assured that the person cutting or divding the treats darn well made sure they were 50/50, because the other sibling got to pick what "half" they wanted.
Perhaps the hot-shot researchers should try that variant; it's one I never hear of in these sorts of studies.
I am so tired of people thinking that chimp, gorilla, and man are family. Oh, yes there may be many similar actions, but I know that I don't have any relatives in this group. The idea that people developed from the ape would still be occurring somewhere in this world if that was true! Has anyone (recently) found any sign that this might be occurring? No, why? Because it didn't happen in the first place. The moneys that is used to prove this concept would be better served by tackling why the USA stills has starving children in our own country. Why our medical care is so expensive those that it need can't get it, (and I am not talking about the garbage that is being pushed down our throats) Just why is it okay to make a killing of illness? These ideas and more deserve the money for studying and would have a better outcome.
Did your imaginary god tell you that?
"The idea that people developed from the ape would still be occurring somewhere in this world if that was true!"
Totally wrong. Humans did not evolve from apes. Both evolved from a common ancestor, and both are still evolving. Evolution in fact predicts that modern apes CAN'T evolve into humans.
Chimps are just like the human race some are real nice and show real love and caring and then there are those that murderous and just plain mean low life no account worthless, with no hope of fixing the turds.