Ravens parallel great apes in flexible planning for tool-use and bartering

The selection procedure differed from the tool condition because the ravens were given three trays in immediate succession (to be comparable with some studies on great apes) so that the subject could select, and later exchange, three tokens in one trial. Experiment 3 tested planning in a self-control context to determine whether ravens can act with future events in mind by disregarding an immediate, valuable food reward in favor of an item that could give access to an even more valued reward occurring only after a 15-min delay. In contrast to a control condition in which all ravens selected the immediate reward on 100% of trials when no tool or token was available (10 trials per subject), subjects selected the tool on average in 73.8% of the trials (min, 8; max, 12) and the token in an average of 73.2% of trials (min, 7; max, 12).

Source: science.sciencemag.org