Studies show dogs have sense of fairness       

RANDOLPH E. SCHMID, AP Science Writer

WASHINGTON – No fair! What parent hasn't heard that

from a child who thinks another youngster got more of

something? Well, it turns out dogs can react the same

way. Ask them to do a trick and they'll give it a try. For a

reward, sausage say, they'll happily keep at it. But if one

dog gets no reward, and then sees another get sausage

for doing the same trick, just try to get the first one to do it

again. Indeed, he may even turn away and refuse to look

at you.

Dogs, like people and monkeys, seem to have a sense of

fairness.

"Animals react to inequity," said Friederike Range of the

University of Vienna, Austria, who led a team of

researchers testing animals at the school's Clever Dog

Lab. "To avoid stress, we should try to avoid treating

them differently."

Similar responses have been seen in monkeys.

Range said she wasn't surprised at the dogs reaction,

since wolves are known to cooperate with one another

and appear to be sensitive to each other. Modern dogs

are descended from wolves.

Next, she said, will be experiments to test how dogs and

wolves work together. "Among other questions, we will

investigate how differences in emotions influence

cooperative abilities," she said via e-mail.

In the reward experiments reported in Tuesday's edition of

Proceedings of the National Academy of Sciences, Range

and colleagues experimented with dogs that understood

the command "paw," to place their paw in the hand of a

researcher. It's the same game as teaching a dog to

"shake hands."

Those that refused at the start — and one border collie

that insisted on trying to herd other dogs — were

removed. That left 29 dogs to be tested in varying pairs.

The dogs sat side-by-side with an experimenter in front of

them. In front of the experimenter was a divided food bowl

with pieces of sausage on one side and brown bread on

the other.

The dogs were asked to shake hands and each could see

what reward the other received.

When one dog got a reward and the other didn't, the

unrewarded animal stopped playing.

When both got a reward all was well.

One thing that did surprise the researchers was that —

unlike primates — the dogs didn't seem to care whether

the reward was sausage or bread.

Possibly, they suggested, the presence of a reward was

so important it obscured any preference. Other

possibilities, they said, are that daily training with their

owners overrides a preference, or that the social

condition of working next to a partner increased their

motivation regardless of which reward they got.

And the dogs never rejected the food, something that

primates had done when they thought the reward was

unfair.

The dogs, the researchers said, "were not willing to pay a

cost by rejecting unfair offers."

Clive Wynne, an associate professor in the psychology

department of the University of Florida, isn't so sure the

experiment measures the animals reaction to fairness.

"What it means is individuals are responding negatively to

being treated less well," he said in a telephone interview.

But the researchers didn't do a control test that had been

done in monkey studies, Wynne said, in which a preferred

reward was visible but not given to anyone. In that case

the monkeys went on strike because they could see the

better reward but got something lesser.

Range responded, however, that her team did indeed do

that control test as well as others in which food was

moved or held in the hand but not given to the dog being

tested.

In dogs, Wynne noted, the quality of reward didn't seem to

matter, so the test only worked when they got no reward

at all.

However, Wynne added, there is "no doubt in my mind

that dogs are very, very sensitive to what people are

doing and are very smart."

On the Net:

PNAS: http://www.pnas.org

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