“Griffin”, a grey parrot in Dr. Irene Pepperberg’s lab, could wait for a better quality reward for up to 15 minutes, even though both treats offered were preferred food items. Griffin displayed delayed gratification for longer than any previously tested avian subject including Goffin’s cockatoos. Fifteen minutes was the longest time evaluated, not necessarily the longest length of time Griffin could wait.
A series of experiment in the late 1960s and early 1970s led by Stanford University psychology professor, Walter Mischel, were used to measure self-control in 3-5 year old children. Each child was given a treat, like a marshmallow, pretzel, or animal cookie, and promised that if she did not eat the treat right away, she would soon be rewarded with a second delicacy. When similar studies have been tried in animals, not surprisingly most species have not performed very well, often waiting only a few seconds (Hillemann et al 2014). Goffin’s cockatoos (Cacatua goffiniana) evaluated by researchers at the University of Vienna could manage to wait up to 80 seconds at best, although these birds had to hold the reward in their beaks, rather than look at it on the table (Auersperg et al 2013). Dogs, primates, and some birds like crows and ravens have done a bit better (Zielinski 2014). The longest any animal (crows) had managed to wait was 10 minutes until Griffin the grey parrot (see key points above) (Fig 1) (Hilleman et al 2014).
Why is Griffin’s achievement significant? From a cognitive point of view, self-control is seen as a critical skill for making future-oriented decisions (Hilleman et al 2014). It can be difficult to choose a delayed reward over an immediate one, even when the delay leads to increased pay-offs (Vick et al 2010). The ability to delay gratification has particular advantages for social animals, which may benefit by sharing.
Of course there are trade-offs that exist between self-control and impulsivity with regards to resource exploitation and competition (Stephens 2008). Impulsivity or immediacy can pay off if delaying food intake increases the animal’s risk for survival (Koepke et al 2015). The longer an animal has to wait for a reward in the wild, the higher the risk of losing the desired item. If the bird waits too long, food can walk or fly away and a waiting bird can also be at risk from predators (Madhusoodanan 2014).
A study in Irene Pepperberg’s lab was led by Adrienne E. Koepke of Hunter College and Suzanne L. Gray of Harvard University. The new results of their work with Griffin, a 19-year-old grey parrot (Psittacus erithacus) are now posted online ahead of print by the Journal of Comparative Psychology. To test the grey parrot’s patience, researchers began by learning his favorite foods. Rewards consisted of pairs constructed from seven highly preferred food items: cereal flakes, dried berries, cashews, almonds, crackers, as well as Nestle® Nerds, and Mars® Skittles candy. Researchers also identified three tiers of desirability existed within Griffin’s food preferences with most favored treats being the candies and his least preferred treat (although still preferred to his regular diet) were berries and cereal (Koepke et al 2015).
The test involved two treats placed in cups, one of which Griffin liked better. After placing the cup containing the less preferred food in front of Griffin, the researcher told him to “wait”. The researcher then took the other cup and either stood a few feet away or left the room. The researcher then would returned after a random length of time ranging from 10 seconds to 15 minutes. If the food was still in the cup, Griffin got the treat for which he was waiting. At every time period tested, Griffin successfully waited at least 80% of the time, even at the maximum 15 minutes. This is the best performance ever seen in an animal, comparable to Mischel’s original results with preschoolers (Zielinksi 2014).
In the early Mischel studies, children used a variety of elaborate strategies to distract themselves from the temptation of the first treat. Similarly, Griffin often displayed various coping mechanisms to deal with long delays like preening, sleeping (or at least sitting quietly with eyes closed), talking to himself, and manipulation of the available reward. For instance, sometimes Griffin tossed the cup containing the less favored treat across the room away (Video 1). Also, like children in one study, Griffin occasionally licked the treat, but did not eat it (Koepke et al 2015).
Video 1. Griffin is instructed to wait and then bides his time as he sits before a tempting (but not favorite) treat. Visit Slate to see a second fun, brief video that compares Griffin to children in the Mischel study.
Griffin entered the experiment with some rudimentary knowledge of the vocal label “wait”. The researchers were careful to stress that he did not interpret “wait” as a command, however he did not have to be trained extensively before beginning the experiment (Koepke et al 2015).
I don’t believe Griffin was unique. Members of other bird species would probably be able to accomplish the same thing, given the right circumstances—Suzanne Gray (Zielinksi 2014)
Who is Irene Pepperberg?
Irene Pepperberg, PhD is a cognitive ethologist with an emphasis on animal behavior and comparative psychology. Irene is currently a Research Associate and Lecturer in the Department of Psychology at Harvard University. Her book, The Alex Studies, describes over 20 years of peer-reviewed experiments on grey parrots, received favorable mention from publications in the New York Times and Science. Her memoir, Alex & Me, was a New York Times bestseller and won a Christopher Award. Irene has presented her findings nationally and internationally at universities and scientific congresses, often as a keynote or plenary speaker, and has published numerous journal articles, reviews, and book chapters (Pepperberg 1999).
Dr. Pepperberg works with grey parrots, teaching them to communicate with humans using the sounds of English speech. She then uses this communication code to test the birds in ways similar to those used with young children (Pepperberg 1999).
In June 1977, in a small laboratory at Purdue University, Irene Pepperberg stood with her arm outstretched toward a large bird cage, trying to coax a quivering grey parrot out of the cage and onto her hand. Just one year earlier, Pepperberg had received her doctorate in theoretical chemistry, having devoted years of her life to drawing up mathematical models of complex molecular structures and reactions, first as an undergraduate at MIT and then through her graduate work at Harvard. Yet, here she was, completely spellbound by this trembling, sentient creature, whom she had named “Alex,” an acronym for the “Avian Learning Experiment,” of which he was to be the subject and star. “Here was the bird I hoped—and expected—would come to change the way people think about the minds of creatures other than ourselves…Here was the bird that was going to change my life forever.” –Irene Pepperberg, Alex & Me (2008)
The media eventually picked up Alex’s story and began to follow Pepperberg’s work. Although Irene was not the first to study avian cognition, she and Alex had the widest impact (Fig 2). Studying an animal that can communicate verbally set Pepperberg’s studies apart. Alex had over 100 words in his vocabulary and he set the idea of “bird brain” on its head.
Griffin has been with Irene since he was 7.5 weeks old and he lived with Alex, now departed, most of his life. Athena is Dr. Pepperberg’s first female grey parrot, hatched in 2013 (Andrews 2014, Pepperberg 2008).
How can I support this work?
Support The Alex Foundation (Fig 3). The Alex Foundation works to support research that will expand our understanding of the cognitive and communicative abilities of parrots and through these findings improve the lives of parrots worldwide.
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