After the dogs had learned to lie down reliably, the researchers surprised them by saying "Do It!" and the dogs did what they saw the person do earlier. In other words, the dogs recalled what they'd seen the person do beforehand, even though they had no particular reason to think they'd need to remember.
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In addition to showing that dogs have episodic memory, the study is the first "to assess memory of actions performed by others, not by the subjects themselves," Fugazza said, adding that it also suggests dogs remember much of what we do all of the time, "although it may seem irrelevant for them."
"This is a skill," she continued, "that might be useful for a species living in a rich and complex environment where there is so much to discover, and their human companions can be considered as knowledgeable partners to learn from."
Next, she and her team plan to investigate whether dogs understand the goals of others, or if they are just imitating the observed movements, regardless of the goal. They are curious about such matters, Fugazza said, because dogs may prove to be a great model for studying the complexity of episodic memory "especially because of their evolutionary and developmental advantage to live in human social groups."
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