Ravens Are Better At Planning Than 4-Year-Olds
The ability to plan for future events is at the core of being human and is of crucial importance in our everyday lives. Previous studies on apes suggest that this ability evolved within the hominid lineage. According to various experiments, great apes can plan across time in tool use and bartering conditions, exhibiting self-control for time intervals up to at least one night.
With this study, however, scientists from Lund University, Sweden, show that ravens can plan for tool-use and bartering events with delays of up to 17 hours, exert self-control, and consider the timespan until future events. Researchers highlight that it is unlikely that such advanced skills could have been present in the last common ancestor of birds and mammals, over 320 million years ago.
Five captive and hand-raised adult ravens were tested. Four individuals took part in each condition (tool or bartering), while one male was too scared of the apparatus. Experiment 1 checked if ravens could select, save and later use either a tool or an exchangeable token that became useful 15 minutes after being chosen. Later, they were also given the opportunity to experience that other objects, used as distractors, did not open the reward giving apparatus. The following day, the birds were exposed to the apparatus, which they could interact with, but without a tool available in order to create motivation for future planning. Thereafter, the apparatus was removed in the presence of the subject. One hour later, the ravens were offered a selection from a tray containing the functional tool and three non-functional distractors.
Each experiment included two conditions: tool-use and bartering with humans. Ravens are not habitual tool users, while bartering has never been observed in the wild. Specifically, the scientists tested if ravens can make decisions for an event 15 minutes into the future (experiment 1), and over a longer interval of 17 hours (experiment 2). Additionally, it was checked if the birds could exert self-control when making decisions for the future, by providing an immediate reward (experiment 3). As most of us well know, self-control is essential when planning as our impulsive demands tend to limit us to the whims of “here and now”. The last experiment tested whether the ravens valued a reward that is offered sooner than in experiment 3, where a 15 minute delay was enforced.
In the tool condition, the subjects successfully selected and used the tool to solve the task at an average of 79%, a percentage lowered significantly due to one of the clever females figuring out how to operate the apparatus without the tool… Meanwhile, in the bartering experiment, on average, the ravens exchanged 78% of the selected tokens. A day later (experiment 2), in the tool condition, the ravens selected and used the tool in 89% of the cases. When presented with distractors and an immediate reward (experiment 3), the birds selected the tool on average in 74% of the trials and the token in an average of 73% of trials. Finally, when the delay was shorter (experiment 4), all ravens walked past the immediate reward, and instead selected and used the functional item in 100% of the trials.
The results suggest that ravens make decisions for their future and that they are planners on par with apes. In the tool conditions, ravens were at least as proficient as tool using apes, whereas in the bartering conditions, the birds outperformed orang-utans, bonobos, and chimpanzees. The first trial performances show that the ravens’ behaviors were not a result of habit formation and that they perform better than 4-year-old children. The clear similarities in performance to great apes in these tasks show what the brains of some birds are capable of. Furthermore, this new knowledge opens up avenues for investigating the evolutionary principles of cognition, as such abilities must have evolved independently in birds.
If still in doubt, animal advocates will now surely find it irrefutable that birds possess impressive cognitive abilities. Since our society seems to value intelligence on human terms, such studies aid the causes of bird welfare and rights by questioning the speciesist status quo.