By Bruce Bower
Don’t write off capuchin monkeys as simpleminded. It turns out that they’re symbol-minded, wielding a mental capacity often regarded as unique to people, researchers say.
Capuchins given laboratory training treat arbitrary tokens as symbols for different foods, according to primatologist Elsa Addessi of the Institute of Cognitive Sciences and Technologies in Rome and her colleagues. The animals then spontaneously choose certain tokens over others in ways that correspond to how they choose certain foods over others. Thus, monkeys typically pick a favored token or food over a less-desirable token or food. But that decision gets reversed if a less-desirable token or food is offered in an amount large enough to make its selection worthwhile.
“Capuchins display a rudimentary form of symbolic reasoning, but they are still far away from reaching the complexity of symbolic reasoning that characterizes humans,” Addessi says.