Association of food location with biological cues in the macaque monkey.

Many animal species including humans are endowed with the ability to use biological cues and can extract information by observing other individuals. This study explored whether the macaque monkey could use biological cue to find a hidden target. When the experimenter hid food in one hand and crossed and uncrossed hands quickly, the monkey had no difficulty in finding the food and correctly reached for the baited hand. However, when the food was hidden in one of two cups and the cups were shuffled, the monkey could correctly select the baited cup only at an equal level of luck. These results indicate that the macaque monkey could associate the location of food with a biological cue better than a non-biological cue and keep it in memory when the target was unseen.