Whenever primate researcher Josep Call goes on a trip, he packs his bag the night before and puts his passport and tickets in its front pocket. The next morning, he checks to make sure they are still there. He fully remembers putting them in the bag, but he looks anyway. We humans are fallible, after all, and we know it--thus we often feel uncertain even when we have little reason to.
Over the past several years Call and his colleagues at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have been studying nonhuman apes such as chimpanzees, bonobos, orangutans, and gorillas to see how much they realize that they are uncertain too--a key component to the kind of self awareness we call consciousness. The experiments take several forms, including placing apes in front of two hollow tubes that they can look through. A human experimenter then places a grape in the back of one of the two tubes, either in the full view of the ape or out of his sight. All the ape has to do to get the food is to touch the right tube.
In one experiment that Call described today during a session entitled "Consciousness in context," the grape was placed in one of the tubes and then the experimenter blocked them for various periods of time (5,20,60, or 120 seconds) so that the animal could no longer see it. The blocks were then removed. The longer the delay, the more likely the apes would look in the tube again before touching it. This finding held for all four ape species tested.
The results demonstrate, Call said, that apes can have doubts about their own ability to recall where the grapes are--a sign of incipient consciousness, even if it does not reach the level of complex human self-awareness. Call concluded by quoting the dictum often attributed to French philosopher Rene Descartes: Dubito ergo cogito, cogito ergo sum--I doubt therefore I think, I think therefore I am.
--Michael Balter
thanks for the great article, I have to agree apes are smarter then what some people give them credit for. 100,000 year evaluation might take them to the next level.