“Decoding ambiguity”: Asian elephants’ (Elephas maximus) use previous experiences and sensory information to make decisions regarding ambiguity

Animals rely on sensory information from the environment to make optimal decisions. However, animals are often faced with incomplete or ambiguous information. Some species use sensory information and previous experiences to generate expectations about ambiguity. To test this, we used a cognitive bias test experimentally modified for Asian elephants ( Elephas maximus ) to investigate how they respond to ambiguous cues after positive (rewarded) and negative (unrewarded) experiences. We manipulated the degree of ambiguity by associating the spatial position and colour of the cues to either previously experienced positive or negative experiences. We demonstrate that elephants use previous experiences, and the valence (affective value) attached to those experiences to make decisions regarding ambiguity. Elephants show a positive bias by opening the ambiguous positive box three times as often and twice as quickly compared to the negative cue. Conversely, they are less likely to open and slower to respond to the ambiguous negative cue. These results are consistent with responses of farm animals and captive wild mammals when faced with unconditioned ambiguous cues with perceptual overlaps. Our findings indicate that when making decisions under ambiguity, animals rely on cognitive and sensory mechanisms. A greater understanding of decision-making mechanisms could aid in understanding animals' responses to their immediate environment with potential implications for conservation and welfare. • Asian elephants form expectations about ambiguous cues based on past perceptual similarities. • Elephants show a negative bias to ambiguous cues in terms of opening an ambiguous box. • The latency of their response to ambiguous boxes is intermediate between positive and negative.