Sunday, November 2, 2008

My Inferiority to Scrub Jays

ResearchBlogging.orgRudy Cerda confesses for the Birds & Reptiles class. Elsewhere, Claire Go has blogged about the same study!

Western Scrub Jay with peanutAs much as I like to think that I plan according to future needs, such as time management in order to write papers, study for exams, and even complete this blog, I know I can only operate under pressure. However, when planning for “essential” needs such as food or snacks, I save the best for last or at least hide some away in case I may need or want any later. For example, I’ll always leave my favorite flavor of candy last because I want that flavor to linger for awhile, or I’ll eat the crust first on a slice of pizza because I’d rather wait to take in the gooey, cheesy goodness on the other side of the piece... but enough of my planning for less than crucial things. Aphelocoma californica, better known as the western scrub jay, may exhibit planning for the future in perhaps a more critical way than I do.

According to the Bischof-Köhler hypothesis, only humans are able to disconnect themselves from their current motivation and plan for the future. Apparently other animals do not have crystal balls to predict their future needs and any future-oriented behaviors are due to either patterns of fixed actions or prompted by current motives. There have been previous studies involving rats and pigeons that have that have only supported the Bischof-Köhler hypothesis by the animals solving tasks involving the future, however, the “future” was only a very short time period. Also, primates have also shown the ability to take actions based on future consequences; however, the motives or reasons for the actions have not been differentiated.

Scrub jays are relatively abundant around campus and I frequently observe jays bouncing around with nuts in their beaks. Every so often I’ll see one that is particularly sneaky and decides to stash its food away as if its saying, “You’re not going take this from me,” or preparing for the budget cuts around campus (or perhaps they can sense the inevitable collapse of the economy!) that may take away their beloved seeds. Raby et al also noticed this behavior in western scrub jays and hypothesized that the jays store food based on anticipation of future need. They predicted that the jays would do this in an area in which they have learned they will be hungry and by storing a particular food item in a place where they know it will not be available.

To test this hypothesis, a total of eight western scrub jays were placed in two different compartments on alternate mornings for six days. In one compartment they were given breakfast and the other they were not. After this training, the birds were given food unexpectedly given food to either eat or store in the evening. If the birds were capable of planning for the future, they would store relatively more food if they were in the compartment in which they were not given breakfast because they would anticipate being hungry the next morning… psychics! And the results displayed their fortune-telling abilities as they stored significantly more food (more pine nuts than powdered nuts) in the compartment in which they had not received breakfast.

To ensure the hoarding of the pine nuts was not associated to a specific compartment, two different types of food were given; a specific food was given in a specific compartment and both types in a third compartment. If the jays had a preference of a certain food they would store more of the “other” food rather than the “same” food when offered to store the food away. The results supported the hypothesis of preferential storing food.

Often I find it hilarious when I see a jay hopping around with something in its beak, it hides the food and about 30 seconds later it’s looking for the food it just sneakily stashed away! Some planning if it can’t even remember where it put its food! In the Raby study, it was stated that the birds were slightly hungry, so perhaps those greedy jays around campus are just playing dumb because they aren’t hungry at that moment in order to fool everyone and plot their takeover of campus and my apartment complex! Well, it’s nice to know that my planning skills may be significantly inferior to a scrub jay’s.


C. R. Raby, D. M. Alexis, A. Dickinson, N. S. Clayton (2007). Planning for the future by western scrub-jays Nature, 445 (7130), 919-921 DOI: 10.1038/nature05575



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