Indian mynahs, Acridotheres tristis, learn about dangerous places by observing the fate of others

Studies of learning have consistently shown that animals form strong associations between aversive events, such as a predatory attack, and the environments in which those events are experienced. Place learning through direct exposure to threat puts the individual at a risk that may be avoided, however, by remembering the location in which encounters between conspecifics and dangerous events are observed. Despite much theoretical work predicting that individuals should rely less on private information and more on public information as the risk of individual assessment increases, there have been no tests of observational spatial memory for potentially dangerous places. We investigated whether Indian mynahs learn about an area in which they observe another individual experience an aversive event, namely capture by a human. Experimental observers watched a human chase, catch and remove a conspecific from a feeding site in which observers were accustomed to feeding. A control group watched a human perform the same capture gestures, but with no mynah present. Analysis of observer behaviour at the feeding site both before and after observational training revealed that experimental observers locomoted more after training than before, relative to control observers, suggesting that mynahs acquired a fear response after watching a predatory attack on a conspecific. It appears that, in addition to learning about the location in which aversive events are experienced directly, animals learn about an environment in which they observe others encounter dangerous events.