Do chimpanzees have "commandments" to which they follow, or is it is
evolution?

Selfless Chimps Shed Light on Evolution of Altruism

By Charles Q. Choi, Special to LiveScience

posted: 25 June 2007 10:19 am ET

Chimpanzees have now shown they can help strangers at personal cost without
apparent expectation of personal gain, a level of selfless behavior often
claimed as unique to humans. Credit: Max Planck Institute

Chimpanzees have now shown they can help strangers at personal cost without
apparent expectation of personal gain, a level of selfless behavior often
claimed as unique to humans.

These new findings could shed light on the evolution of such altruism,
researchers said.

Scientists think altruism evolved to help either kin or those willing and
able of returning the favor‹to help either one's genetic heritage or oneself.
Humans, on the other hand, occasionally help strangers without apparent
benefit for themselves, sometimes at great cost.

To investigate when chimpanzees might aid either humans or each other,
researchers studied 36 chimps at Ngamba Island Chimpanzee Sanctuary in Uganda
that were born in the wild. In experiments, each chimp watched a person they
had never seen before unsuccessfully reach for a wooden stick that was within
reach of the ape. The person had struggled over the stick beforehand,
suggesting it was valued.

Scientists found the chimpanzees often handed the stick over, even when the
apes had to climb eight feet out of their way to get the stick and regardless
of whether or not any reward was given. A similar result with 36 human
infants just 18 months old yielded comparable results.

"Chimpanzees and such young infants both show that some level of altruism may
be innate and not just a factor of education," said developmental and
comparative psychologist Felix Warneken at the Max Planck Institute for
Evolutionary Anthropology at Leipzig, Germany. "People say we become
altruistic because our parents teach us so, but that young children are
originally selfish. This suggests maybe culture is not the only source of
altruism."

Further testing

Still, humans at the sanctuary provide the chimpanzees food and shelter, so
helping people out could simply be in their best interests. Experiments were
then needed to see how willing the apes were to help out unrelated chimps.

The researchers set up closed rooms that each held a piece of banana or
watermelon. The only way for a chimp to get in was if an unrelated spectator
ape released a chain to open the room. Warneken and his colleagues found the
spectators often altruistically helped the other chimps get the fruit, even
if they got no reward themselves, findings detailed June 25 in the journal
PLoS Biology.

These findings suggest the roots of human altruism go deeper than previously
thought, reaching back as far as the last common ancestor of humans and
chimpanzees.

"There is a biological predisposition to altruistic tendencies that we share
with our common ancestor, and culture cultivates rather than implants the
roots of altruism in the human psyche from primordial forms to more mature
ones," Warneken told LiveScience.

Primal differences

Primatologist Frans de Waal at Emory University in Atlanta noted he recorded
hundreds of cases of altruism among chimpanzees, "but skeptics like to
downplay the evidence by saying it is not based on controlled experiments."
These new experiments "thus confirm what observers of chimpanzees had said
all along."

Still, altruism is rarely seen in chimps in the wild, and past research from
the Max Planck Institute and others actually suggested that chimpanzees were
not capable of human-like altruism. For instance, when chimps had the option
of pulling a bar to feed either just themselves or themselves and another at
no cost, UCLA primatologist Joan Silk and her colleagues had found the apes
were no more likely to choose either option.

"In that experiment, maybe they were so occupied for retrieving food for
themselves that they had no attention to spare for others," Warneken said.
"So one difference between humans and chimps might be the ability to read the
intentions of others and discriminate whether help is needed or not. You
might have to make it very obvious that there's a problem the other faces."

Also, if chimps feel there is little chance they can get food for themselves,
"maybe altruistic tendencies collapse," Warneken added. "For humans and
chimps, selfish and altruistic motives are in competition with each other,
and it could be that with chimps, selfish motives have to be pushed far off
to the side to make room for altruism. So what distinguishes humans and
chimps is not whether or not chimps have altruism but how fragile altruism
might be."

Silk noted future experiments could test "how much the chimps are really
willing to give up for such altruism." She added the experiments Warneken and
his colleagues performed could be conducted with her own chimps, to see
whether the absence of altruism they saw before "was based off the task we
had them perform, or perhaps the individuals themselves."

http://www.livescience.com/animals/070625_chimp_altruism.html