by Elizabeth Yang ’22
Published Mar. 20th, 2021
Put yourself in the shoes of a child with a yummy marshmallow in front of you. You’re told that you can either eat the marshmallow this instant or have the chance to receive one more if you patiently wait for 15 minutes.
This is the premise of the famous Stanford marshmallow experiment. Designed to analyze self-control, it assesses the children’s ability to delay immediate satisfaction in return for greater future rewards.
In early March, the experiment was conducted among six cuttlefish placed in two chambers that had treats behind transparent doors. Both groups were trained to recognize three symbols that signified how the doors would open: a circle meant that the door would immediately open, a triangle meant that there would be a delay, and a square meant that it would not open at all.
In one chamber, a prawn was easily accessible behind the open door with a circle. Simultaneously, more delicious live shrimp were placed behind the triangle-marked door, only obtainable if the cuttlefish waited for a certain amount of time. If the cuttlefish tried to eat the prawn, the live shrimp were quickly removed. The shrimp was placed behind the square-marked door in the other chamber, entirely inaccessible for the cuttlefish.
The results were fascinating. All of the cuttlefish in Chamber 1 resisted the urge to go for the prawn, knowing that they could eat the shrimp if they waited. On the other hand, those in Chamber 2 did not bother waiting, knowing that the door would never open.
From this, researchers discovered that the cuttlefish were able to exert a fantastic amount of self-control, comparable to that of larger-brained vertebrates, like parrots and chimpanzees. Unlike these creatures, however, cuttlefish do not use these abilities for factors like food caching and prosociality, prompting questions as to why they have developed such skills in the first place.
Several scientists have associated this behavior with how cuttlefish hunt. “Cuttlefish spend most of their time camouflaging, sitting and waiting, punctuated by brief periods of foraging,” says Alexandra Schnell, a behavioral ecologist who led the team of researchers in the experiment. “They break camouflage when they forage, so they are exposed to every predator in the ocean that wants to eat them. Delayed gratification may have evolved as a byproduct of this, so the cuttlefish can optimize foraging by waiting to choose better quality food.”
Cuttlefish, along with their cephalopod family members, including octopuses, nautiluses, and squids, have been long-known to be some of the world’s most intelligent creatures. For years, scientists have analyzed their swift abilities to acquire and recontextualize information, behaving in ways vastly different from their neighbor invertebrates. Having the capacity to pass a test conceptualized for human beings opens up a whole new world of possibilities of these intriguing creatures’ cognitive abilities.