Study
Episodic-like memory during cache recovery by scrub jays
Clayton, Nicola S.; Dickinson, Anthony
Nature, 1998
Scrub jays cached two foods: perishable wax moth larvae, which they prefer, and peanuts, which keep. They were allowed to recover the caches after either a short or a long delay, having learned separately that larvae degrade over time.
- Studied in
- Aphelocoma californica
- Sample size
- hand-raised scrub jays across cache-recovery trials
After a short delay jays searched for larvae; after a long delay they went straight to the peanuts, ignoring larvae they had cached themselves. They combined what was cached, where, and how long ago.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Scrub jays form integrated memories of what, where and when — the behavioural signature of episodic memory.
How NatureHQ reads it
The founding result in animal episodic memory, and the source of a caution that has followed it ever since. The authors called it "episodic-*like*" deliberately: the jays demonstrably integrate content, place and time, and nothing in the design shows they *re-experience* the caching event, which is what episodic memory means in humans. That hyphenated qualifier is routinely dropped in coverage, and dropping it changes the claim substantially.
- Shows integration of what, where and when — not subjective recollection, which no behavioural design can reach.
- Hand-raised captive birds with extensive experience of the apparatus.
- Whether the jays track elapsed time or a decaying memory trace is difficult to separate.
The jay that remembers which cache has gone off
Can a bird remember not just what it hid and where, but how long ago — and act on all three at once?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Animal memory
Some animals remember what they did, where, and how long ago — but that is not the same as remembering the moment
Animal memory
Apes remember what was hidden, where, and how long ago — and act on all three
Seed dispersal
The biggest benefit of dispersal is not finding new ground — it is not landing under your parent
Oak trees
Acorns fall straight down. Jays are what carry them anywhere useful
Published by: Nature PortfolioPublished in a Nature Portfolio journal.
This reference was resolved automatically against Crossref and OpenAlex on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-09.