How Monkeys Learned to Wash Potatoes
There is a myth that dates back to 1965 of a “collective consciousness” within monkeys found on small islands off the coast of Japan. The “Hundredth Monkey Phenomenon” as it began to be called, was based on the studying of free-roaming macaques. In 1952, scientists introduced sweet potatoes to the monkeys on Koshima Island, tossing them onto the beach for the macaques to find and pick up. The following year scientists discovered that a young monkey called “Imo” was washing sand off the potato by dipping it into the water; This could have been for many reasons, either they didn’t like the taste of sand, the potatoes tasted better with salt on them, or it just looked more appetizing. Either way, Imo kept the behavior, continuing to wash her sweet potatoes she found on the sand. Over the next few years from 1952 to 1958, researchers found other monkeys copying the practice, and teaching to it their offspring as well. As time went on, more and more of the Macaques troops mimicked the same motion. The controversy came when researchers claimed that the habit seemed to have jumped natural barriers and spontaneously appeared in other colonies on different islands and even on the mainland. This resulted in further publications on the idea of a “collective consciousness”, an idea favored by psychologists such as Carl Jung, who publicized the term “objective psyche”, an idea referring to a segment of a genetically inherited unconscious mind.
Although the story of the “Hundredth Monkey Phenomenon” was later debunked as false, the idea of an information cascade resulting in the mimicking of washing sweet potatoes was quite real. We learn in class that information cascades are the result of sequential decision making even in the face of personal knowledge. I’m sure that most of these monkeys were perfectly fine eating their sandy sweet potatoes, so why did they all of a sudden start washing them? The reason, simply put, is the result of a slow, sequential creation of social proof for a “superior” way to eat sweet potatoes. If one day you saw someone washing their apples before eating, maybe you, too, would start washing your apples in fear of something wrong with the surface of your fruit. Even if you were pretty sure your apples were fine, you’ve eaten them in the past and haven’t died yet, you might wash them just to be safe. Over time, as you have greater exposure to different people seeing you wash your apples, the idea spreads and 6 years later everyone is washing their apples. The idea of information cascades can play a powerful motivator when there isn’t known information to the contrary, without a reason to believe that sandy potatoes made superior meals, there isn’t much reason not to start washing them. And although the monkeys in Japan didn’t really develop a collective consciousness about washing sweet potatoes, those who saw and made their own decision regarding the state of their own potatoes did, and then decidedly chose to wash them.
https://hilo.hawaii.edu/~ronald/HMP.htm