The study was conducted using chimps housed at the Wolfgang Köhler Primate Research Center in Germany. Researchers set up an experiment in which they allowed the chimps to see them hiding food. Then they let one chimp go search for the food, unseen by the others.
If Chimp A had the opportunity to look for the food in advance, then Chimp B was less likely to check the place he saw the researcher hide the food before.
This shows that the chimps were able to guess at what the other chimps would likely do in a situation. If Chimp B knows that he would have looked under the left side of the table, then he presumes that Chimp A would do the same and therefore he estimates that the food from under that spot is already gone, so there’s no point in searching there.
There is a subtle but important difference between figuring out what others know, and figuring out what others might think. Chimpanzees have already been shown to be capable of the former; they can easily figure out what others know. One example is that subordinate chimpanzees will eat food first if they know the dominant chimps – who would normally get first dibs on food – cannot see them.
This is the first time, however, that chimpanzees have been shown to be capable of determining what others might think.
From an ethical standpoint, it is another piece of evidence that intelligence isn’t a dichotomy with us on one side and nonhuman animals on the other. The difference in cognitive capabilities between us and animals is almost universally cited as justification for our treatment of animals, but the more that we learn about animals, the more we learn that intelligence is a gradient.
We’re consistently learning that animals are capable of mental functions that we once thought were exclusive to humans.
Humans have been woefully ignorant of so many aspects of animal physiology and brain function for so long that we are appropriately astounded by the new information that we gather.
The ethical question isn’t whether or not chimpanzee intelligence should give them some special status above other animals and should excuse them from cruel treatment. The ethical question is whether we can – in light of viewing intelligence as a gradient – come up with logical justification for drawing a line of moral consideration anywhere in the animal kingdom. I don’t think we can.
The more we learn about animals, the more we learn that we are just like them: sentient animals inhabiting this planet together. If you can look into a chimp’s eyes and see a little bit of yourself, why can’t you look into a pig’s eyes or a cow’s eyes and see a little bit of yourself there too?