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July 1st, 2009
Spark Blog: Squirrels Bury Nuts, But Are They Planning Ahead?

by Graham Chedd

The Human Spark crew films Alan Alda and Dan Gilbert deep in conversation. Photo: Maggie Villiger

Walking the dog this morning and enjoying the sound of birds singing reminded me of an entertaining exchange Alan had with Dan Gilbert of Harvard University, and author of the book Stumbling on Happiness. The birds sounded happy, but of course we can’t infer that: the real reason for their singing is to find a mate or defend a territory, and so get to pass on the genes for singing.

Dan and Alan were chatting on the Weeks Bridge over the Charles River about Dan’s top pick for what makes us human: the ability to “prospect,” the opposite of retrospect — in other words, to think about the future, “to explore alternative worlds without having to live in them.” While Dan agrees that other animals can look forward in time “in very small amounts,” we do it “orders of magnitude differently and better than any other animal.”

There were acorns on the ground around the bridge, and I’d given one to Alan to remind him to ask Dan a question about whether squirrels are thinking about the coming winter when they bury nuts.

Photo by Diliff, under a CC license

Alan: So what’s the squirrel doing when it plants the nut?

Dan Gilbert: It’s planting a nut, in the here and now, because the day is getting shorter, less light is hitting the little squirrel eye and going into its little squirrel brain, and so it runs the “nut burying program,” in the same way your computer can run programs without thinking about — knowing about the future. You know, if Ben Franklin were to come into the present and see a computer, he would say, there must be a little man inside it. There must be someone inside who knows what to do and what’s going to happen. That would be wrong.

We’re never tempted to anthropomorphize our computers because we understand the circuitry that’s making them run. We don’t understand squirrel circuitry or dog circuitry or cat circuitry well enough, and so we look at the dog, cat and squirrel and say it must know what’s coming, because if I were doing that, I’d do that because I know what’s coming.

Alan: So we assume the squirrel is at an unconscious level mapping where it put the nut, have we found out they just keep digging till they find the nut?

Dan: We can’t know for sure what the squirrel’s doing in its own mind, but I would suggest that squirrels do everything at the unconscious level because they’re not conscious, so everything they’re doing is some sort of program. A squirrel is an amazing automaton. Now that’s not with any disrespect to squirrels…

Alan: If we get letters from squirrels, I’m sending them to you. I don’t want to deal with squirrel letters…

Or chimpanzees, if it comes to that. There is much debate among researchers about whether chimps plan for the future. Mostly this revolves around whether chimps think how they might use a rock or stick in some later task, and the debate’s been further enlivened recently with the report of the chimp in the Danish zoo apparently stockpiling stones to throw at visitors. But even if they do think ahead an hour or two, while that’s more than any other animal that’s been studied, Dan Gilbert is pretty sure they’re not planning for retirement.

- Graham Chedd

  • floydsghost

    Planning ahead and thinking of the future may be a human spark but let’s dont pat ourselves on the back just yet! There’s alot of things we still do without thinking!

  • cinnamonape

    I think that squirrels pretty much must do things without “thinking ahead” on this. After all, many squirrels have never been successfully through a winter, so they must either be copying what other squirrels are doing without a clue as to why…or running off some “program”…or a little of both. Of course, once successful they might get better at doing this, remembering where nuts are hidden, etc.

    But I’ve heard that lots of squirrel caches get “lost” and these end up growing into seedlings.

  • julie finton

    Isn’t it just as bad science to assume squirrels aren’t thinking as it would be to assume they were?
    Laboratory mice can learn how their actions will result in rewards or not — and no offense to Pavlov, but how conscious or unconscious this conditioned behavior is we have no way to know — so why shouldn’t squirrels? Meerkats teach their young the risky task of catching scorpions by disabling the stinger for them; why wouldn’t squirrels learn from their mothers how to bury and retrieve their food?

  • Jim Mauch

    Why do we run the eat the doughnut program over and over again when we know that the program is not good for us?

  • Bonnie

    Hi,
    I just watched Charlie Rose’s show about brains. A guest woman told a story about a fish. If the fish has a fight with another fish and looses..it knows it lost and remembers that. If it sees that other fish fight and loose to another larger fish, it knows,”don’t even bother”.
    If a fish can do all that thinking and remembering…couldn’t a squirrel do as much or more?

  • Darlene

    Bonnie, I think that they do. I have a 14 yeare old squirrel who lives in the house and has his own cage/ room. He is amazing. He plays games me me for an hour in the morning… adaptations of hide and seek, some gentle squirrel grooming behaviors, and an occasional kiss on my cheek or my lips, and he makes an amazing number of sounds. He immitates a Chihuahua bark… no problem. He responds to my verbal requests, and he pays attention when I call his name. I think that that he communicates also with movement… tail flipping and body posture.

  • Steven owen

    On another thought if they are planting their nuts what if they are somewhat aware o the future and that they unlike humans want somewhere nice for their siblings to grow up in. Maybe the idea is to eat a few and bluff the rest so that they grow into a beautiful tree and to create a beautiful and habitable future. Thinking at it’s best maybe they are preparing for the future unlike us humans who are very good at destroying the world.

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