Cephalopods Exhibit Cognitive Skill in Modified Delayed-Gratification Experiment
Oceanic Masters of Self-Control
The remarkable intelligence of cuttlefish has come to light following a study that demonstrates they can pass a specially adapted underwater version of the well-known “marshmallow test” –a test of self-control that is usually given to children. The study, led by Alexandra Schnell from the University of Cambridge, along with Roger Hanlon of the Marine Biological Laboratory and their team, found that cuttlefish can wait for better rewards, demonstrating an ability to delay gratification.
Exploring Intelligence in Cephalopods
Traditionally, the marshmallow test assesses if young children can forego a small treat now for a larger one later, testing their ability to wait for 15 minutes. Translating this test to an aquatic environment, researchers presented cuttlefish with an immediate but less appetizing food option alongside a more attractive live grass shrimp that was momentarily out of reach. While some cuttlefish succumbed to temptation, others displayed remarkable restraint, holding out for more than two minutes to capture the more appealing live prey.
“The faster a cuttlefish learned the association between the food and the signals we gave, the more likely they were to exhibit restraint,” Schnell stated, linking their ability to wait to sharper cognitive processes. The investigation proceeded to include reversal learning tasks where cuttlefish needed to unlearn and relearn associations between food and cues. Those that displayed self-control were also more adaptable to these rule changes, indicating potential overlapping neural pathways that govern self-discipline, learning, and memory.
The Evolutionary Edge Gained by Patient Predators
The team of researchers suggest that the cuttlefish’s propensity for self-restraint is likely an evolutionary adaptation related to their susceptibility to predators. “Foraging poses considerable risk since it breaks their camouflage and attracts attention,” Schnell observes, positing that by holding out for higher quality prey, cuttlefish not only improve their foraging success, but also minimize the risk of predation.
Published in the journal Proceedings of the Royal Society B, the study signifies the first documented correlation between self-control and intelligence in a non-primate species, shedding light on the broader capacity of delayed gratification across diverse evolutionary branches.
Broader Perspectives on Intelligence in Diverse Species
This research reinforces the idea that intelligence and complex behaviors are not exclusive to animals with larger brain sizes. Other marine organisms like octopuses and squids have captured scientific interest with their problem-solving prowess, and now, cuttlefish contribute evidence to the concept of convergent evolution – the evolution of similar traits in different species as a response to comparable environmental pressures.
The results elicit new examinations into cognitive development across invertebrates, challenging the traditional view that advanced thought capabilities, like strategic planning and problem-solving, are unique to vertebrates. This broadens the scope of understanding intelligence and patience as universal strategies for survival across various species.
