It's a continuing debate in how far humans and other primates have altruistic tendencies.
We found a method with which we can test human infants at 14 to 18 months of age.
They have not gone to school yet.
But maybe they already have some of these behaviors that show that they're helpful and altruistic.
If we find something of this altruism both in chimpanzees and young infants,
we can conclude that it's not human culture, human teaching,
that is the only source of helping behaviors and altruism,
but that, somehow, by natural endowment, we have the capability to develop this.
To test whether human infants are helpful or not, we set up situations for the children
in which an adult was performing certain actions--
very everyday things--and then suddenly a problem occurred.
And then the question was whether the infants just walking around in the room would see that,
understand what the problem is that the adult has, and then walk over and help by,
for example, picking up the object and handing it to the adult.
How we did it with the chimpanzees was that we tried to find structurally similar tasks.
The difficulty with the chimpanzees is that you have to use objects that are familiar to them.
When we tested whether children would help or not,
we expected them to help in some of the situations,
but we were surprised that they would help in a variety of very different situations.
We were also surprised that the children would help so spontaneously,
usually within 10 seconds after the problem.
With the chimpanzees we expected that they would not help at all.
They didn't gain anything out of their helping.
They were not rewarded with food or anything.
What we found then was that the chimpanzees helped only in the situations
where someone was unsuccessfully reaching for an out-of-reach object.
In our helping study, the prediction with the human infants was that they would distinguish
between situations in which help is needed and situations in which help is not needed.
So we set up situations that were highly similar.
In one case someone was accidentally dropping an object on the ground
and unsuccessfully reaching for it compared
with situations in which he threw the object on the floor on purpose.
And our prediction was that the children should--
at least in some of these situations--distinguish that.
And that's what we found.
And with the apes we thought that they would just not distinguish between the two.
The finding was that they did distinguish.