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  • From: "Josh Greenman" <josh.greenman AT gmail.com>
  • To: Monkeywire <monkeywire AT lists.ibiblio.org>
  • Subject: [monkeywire] The Evolution of Economic Rationality: Do Monkeys Understand Money?
  • Date: Mon, 28 Jul 2008 09:33:39 -0500

http://blogs.psychologytoday.com/blog/cultural-animal/200807/the-evolution-economic-rationality-do-monkeys-understand-money

The Evolution of Economic Rationality: Do Monkeys Understand Money?

By Roy F. Baumeister on July 15, 2008 in Cultural Animal

(This post was coauthored with Kathleen D. Vohs.)

Money is a powerful force in human life and affairs. Its very power
gives pause to those who look to evolution for full explanations of
human behavior, because money has not existed long enough to have
influenced evolution. By some estimates, money only goes back a couple
thousand years, which is too short even to have influenced human
evolution.

Still, one can get some clues as to how evolution prepared us for
money from the burgeoning research that seeks to present animals with
economic choices. To gain perspective on human financial decisions,
one may ask, what would monkeys do?

Keith Chen and Marc Hauser at Yale University taught monkeys about
resources that bear a strong resemblance to money. Monkeys don't care
about money, per se, but they do care about marshmallows. (This
already is a difference of gigantic proportions in that monkeys must
learn about resource-exchange using something that is already a
primary reinforcer - food - whereas humans can extend the range of
their motivations to secondary reinforcers.) A resource (marshmallows)
exchange task was introduced whereby pressing a lever would give
another monkey a marshmallow; hence this was a task that involved a
bit of altruism. Not only were monkeys taught about the game. Two
specific monkeys were conditioned (entrained), such that one always
pulled the lever for his monkey partner (thus being a very generous
partner) and the other never pulled the lever for his partner
(stingy). Then they let these conditioned monkeys play the game with
other monkeys. Monkeys that played with the highly generous monkey
figured it out and quickly took advantage of him. Monkeys that played
with the stingy monkey also figured it out quickly and subsequently
shunned or were aggressive toward him.

Thus, monkeys can at least understand and respond effectively to the
difference between a generous provider and a tightwad. Still, the fact
that these differences had to be done with marshmallows instead of a
more abstract representation of value (which is what money is)
suggests a limited capacity to use or understand money.

Other studies have shown that monkeys take any handout above zero that
is offered to them in a version of what, in humans, is called the
Ultimatum Game. In the Ultimatum Game, one person is designated the
Proposer (who thus offers the ultimatum) and the other becomes the
Responder (who decides whether to take it or leave it). The Proposer
offers an amount of money to the Responder out of a total amount that
the Proposer has been given by the experimenter - usually this is $10.
The whole game involves the Proposer offering the Responder an amount,
which the Responder has the option to accept or reject. Accept the
split and both sides get what was offered; reject it and both sides
get no money at all. This obviously not an evenly matched game. The
Proposer has the power to make the ultimatum. All the Responder can do
is either take whatever is offered or say no, which is costly to both
players.

When humans play this game, the Responders will sometimes refuse
offers that they deem too low. Depending on the person and the
circumstances, people tend to refuse offers below 20% of the total.
Monkeys, however, have no such scruples, and will take anything above
zero.

You can look at the monkeys' responses in different ways. One way is
that they are not bothered with issues of pride, self-esteem, and
fairness. After all, a human is humiliated to accept a tiny share,
especially if he or she expected an equal split. They know that the
other person could have divided the pay equally and perhaps should
have - but chose instead to claim the lion's share for self and offer
only a measly sop. Monkeys apparently either do not understand that
they should be embarrassed, or they do not care.

Yet another way of looking at it is to suggest that monkeys are
actually pretty smart. Economists continue to scratch their heads at
the results of studies with the Ultimatum game. They assume that
people are basically oriented to maximize their own profits. If you
and someone else worked equally to earn $100, and that person has the
power to divide it and chooses to offer you only one dollar while
keeping $99 for himself, well, you are still better off with one
dollar than with nothing. Hence economic rationalists find it slightly
scandalous that people ever refuse any offer. Economists think that if
people were true to financial logic, they would act more like monkeys.

Thus, when monkeys play, they behave as economists would have humans
do - they accept any offer above zero. This means that, although
rational (they have more when they leave the game than when they
entered), monkeys are not sensitive to issues of fairness. Humans most
certainly are. Humans feel all kinds of self-conscious emotions when
they receive more than they think they ought to receive. Not always,
of course, but it happens.

Other work suggests that monkeys do not have a fully developed sense
of fairness. There are signs that they are acutely sensitive to
getting less than their fair share, such as if they see another monkey
getting more than they get. If you have two dogs and give one a
biscuit treat, the other will look at you with a mixture of expectancy
and indignation. Getting less than your fair share is called being
underbenefited, and many animals seem to have that.

But a fully developed sense of fairness means that you are
uncomfortable with being overbenefited as well. That is, it bothers
you to get more than your fair share. Here is where humans seem to
part company with other creatures.

What happens when monkeys overbenefit from an exchange - do they
experience guilt, embarrassment, shame, or try to rectify the
situation? Apparently not.

This may be why humans embraced money: because it allows for trade of
resources on the basis of equity, which is subject to exchange rates.
That is, imagine that I ask you to paint my living room walls; then by
the virtue of the fact that I wanted you to paint my walls, I may not
be skilled at or want to paint your walls. But I can repay you in
another currency, namely money. In this way, humans can correct
overbenefits in a manner that is separate from the original payment
(in this case, wall painting).

Humans' emphasis on fairness can be seen in other instances as well.
One important study showed that people will spend their own money to
punish others who do wrong. In these studies, even at a cost to
themselves, people were willing to inflict harm on those who took
advantage of others.

So maybe Adam Smith, that seer of economic truths, was right after all
when he wrote, "Nobody ever saw a dog make a fair and deliberate
exchange of one bone for another with another dog. Nobody ever saw one
animal by its gestures and natural cries signify to another, this is
mine, that yours; I am willing to give this for that."



  • [monkeywire] The Evolution of Economic Rationality: Do Monkeys Understand Money?, Josh Greenman, 07/28/2008

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