Can animals recall the past and plan for the future?

  title={Can animals recall the past and plan for the future?},
  author={Nicola S. Clayton and Timothy J. Bussey and Anthony Dickinson},
  journal={Nature Reviews Neuroscience},
According to the 'mental time travel hypothesis' animals, unlike humans, cannot mentally travel backwards in time to recollect specific past events (episodic memory) or forwards to anticipate future needs (future planning). Until recently, there was little evidence in animals for either ability. Experiments on memory in food-caching birds, however, question this assumption by showing that western scrub-jays form integrated, flexible, trial-unique memories of what they hid, where and when… 
Animals may not be stuck in time
Mental time travel in animals: A challenging question
The comparative study of mental time travel
A raven's memories are for the future
It is shown that ravens anticipate the nature, time, and location of a future event based on previous experiences, and this results suggest that planning for the future is not uniquely human and evolved independently in distantly related species to address common problems.
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There is accumulating evidence that animals show behavior that when reported in humans would be taken as evidence for cognitive time travel, and the ability of animals to anticipate future events (future planning) has also been reported.
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It is argued that although the criterion proposed by this hypothesis provides a test for an explicit representation of a future time, it does nothing to get at whether planning for this future is mediated by semantic or episodic processes.
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It is argued that the capacity to simulate possible future events, based on episodic memory, enhanced fitness by enabling action in preparation of different possible scenarios that increased present or future survival and reproduction chances.


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It is argued that the human ability to travel mentally in time constitutes a discontinuity between ourselves and other animals and allows a more rapid and flexible adaptation to complex, changing environments than is afforded by instincts or conventional learning.
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Evidence that great apes and other primates may possess episodic‐like memory is presented and the functional significance of episodic memory in nonhuman primates is speculated on.
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It is shown that scrub jays remember ‘when’ food items are stored by allowing them to recover perishable ‘wax worms’ (wax-moth larvae) and non-perishable peanuts which they had previously cached in visuospatially distinct sites.
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This article considers the role of mental time travel in human evolution. A central thesis is that other primates, although having memory and expectation, do not possess the same ability to live in
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A realignment of organization of memory is suggested such that declarative memory is defined in terms of features and properties that are common to both episodic and semantic memory, which gives greater precision to the Vargha‐Khadem et al. study.
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An 11-year-old female chimpanzee that had already learned a large number of arbitrarily designated geometric forms (lexigrams) watched as an experimenter hid an object in the woods outside her outdoor enclosure and could interact indoors with a person who did not know that an object had been hidden, let alone the type or location of the object.