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Sanchez, A. H.

Publications and source records attributed to Sanchez, A. H..

2 recordsLinked to original sources

Third-party imitation is not restricted to humans

Imitation of cultural practices is ubiquitous in humans and often involves faithful copying of intransitive (i.e., non-object directed) gestures and societal norms which play a crucial role in human cultural evolution. Apart from learning these directly from a tutor, humans often learn passively as third-party observers from the interactions of two or more individuals. Whether third-party imitation has evolved outside humans remains unknown. In the current study, we investigated whether undomesticated blue-throated macaws could imitate in a third-party setting. A naive test group (N=6) passively observed a conspecific demonstrator performing improbable intransitive actions in response to specific human gestural commands. Directly afterwards, the observer received the same gestural commands and performance-contingent rewards. An equally naive control group (N=5) was tested correspondingly, in the absence of third-party demonstrations. The test group learned more target actions (mean=4.16 versus mean=2.2) in response to the specific commands, significantly faster and performed them more accurately than the control group. The test group also spontaneously imitated some of the actions even before they received any gestural commands or rewards. Our findings show that third-party imitation, even for intransitive actions, exists outside humans, allowing for rapid adaption to group specific behaviours and possibly cultural conventions in parrots.

animal behavior and cognition↗

Awareness of the future: Dolphins know when they need to remember for the future

In humans, awareness of an upcoming memory test enhances intentional encoding and improves memory recall. Here, we investigated whether dolphins exhibit similar future-oriented encoding of information known to be needed in the future. Dolphins were trained to remember specific, randomly assigned actions for later re-enactment, with either immediate or delayed recall. When an unexpected delay was introduced in trials anticipating immediate recall, memory was retained for only 13 seconds, suggesting working memory encoding. However, when instructed to expect delayed recall, dolphins accurately reproduced actions after delays even after 16 hours. These results suggest that dolphins, anticipating future need, intentionally encode actions to be performed in the future into long-term memory, implying prospective encoding and prospective memory capacities. Their memory also displayed key features of episodic memory: encoding occurred in a single episode, and memory was declarative, as the action itself declared its content. Moreover, dolphins more effectively recalled self-performed actions compared to gestural codifications of the same actions, mirroring the human-typical "enactment effect" and supporting episodic-like memory over semantic memory. Our findings indicate that dolphins show awareness of future memory demands and seem to use a future-oriented, episodic-like memory system, capable of storing prospectively encoded, intended actions in long-term memory.

animal behavior and cognition↗