Joshua Klein: The intelligence of crows

401,393 views ・ 2008-05-19

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00:18
How many of you have seen the Alfred Hitchcock film "The Birds"?
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Any of you get really freaked out by that?
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You might want to leave now.
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(Laughter)
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So this is a vending machine for crows.
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Over the past few days, many of you have been asking,
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"How did you come to this? How did you get started doing this?"
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It started, as with many great ideas,
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or many ideas you can't get rid of, anyway,
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at a cocktail party.
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About 10 years ago, I was at a cocktail party with a friend of mine.
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We were sitting there, and he was complaining about the crows
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that were all over his yard and making a big mess.
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And he was telling me we ought to eradicate these things,
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kill them, because they're making a mess.
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I said that was stupid,
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maybe we should just train them to do something useful.
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And he said that was impossible.
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And I'm sure I'm in good company in finding that tremendously annoying,
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when someone tells you it's impossible.
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So I spent the next 10 years reading about crows in my spare time.
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(Laughter)
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And after 10 years of this, my wife said,
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"You've got to do this thing you've been talking about,
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and build the vending machine."
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So I did.
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But part of the reason I found this interesting is,
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I started noticing that we're very aware of all the species
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that are going extinct on the planet
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as a result of human habitation expansion,
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and no one seems to be paying attention to all the species
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that are actually living; they're surviving.
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And I'm talking specifically about synanthropic species,
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which have adapted specifically for human ecologies,
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species like rats and cockroaches and crows.
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And as I started looking at them, I was finding that they had hyper-adapted.
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They'd become extremely adept at living with us.
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And in return, we just tried to kill them all the time.
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(Laughter)
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And in doing so, we were breeding them for parasitism.
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We were giving them all sorts of reasons to adapt new ways.
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So, for example, rats are incredibly responsive breeders.
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And cockroaches, as anyone who's tried to get rid of them knows,
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have become really immune to the poisons that we're using.
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So I thought, let's build something that's mutually beneficial;
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something that we can both benefit from,
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and find some way to make a new relationship with these species.
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So I built the vending machine.
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But the story of the vending machine is a little more interesting
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if you know more about crows.
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It turns out, crows aren't just surviving with human beings;
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they're actually thriving.
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They're found everywhere on the planet except for the Arctic
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and the southern tip of South America.
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And in all that area, they're only rarely found breeding
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more than five kilometers away from human beings.
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So we may not think about them, but they're always around.
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And not surprisingly, given the human population growth,
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more than half of the human population is living in cities now.
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And out of those, nine-tenths of the human growth population
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is occurring in cities.
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We're seeing a population boom with crows.
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So bird counts are indicating
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that we might be seeing up to exponential growth in their numbers.
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So that's no great surprise.
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But what was really interesting to me was to find out
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that the birds were adapting in a pretty unusual way.
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And I'll give you an example of that.
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This is Betty. She's a New Caledonian crow.
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And these crows use sticks in the wild
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to get insects and whatnot out of pieces of wood.
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Here, she's trying to get a piece of meat out of a tube.
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But the researchers had a problem.
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They messed up and left just a stick of wire in there.
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And she hadn't had the opportunity to do this before.
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You see, it wasn't working very well.
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So she adapted.
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Now, this is completely unprompted; she had never seen this done before.
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No one taught her to bend this into a hook
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or had shown her how it could happen.
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But she did it all on her own.
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So keep in mind -- she's never seen this done.
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(Laughter)
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Right.
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(Laughter)
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Yeah. All right.
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(Applause)
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So that's the part where the researchers freak out.
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(Laughter)
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It turns out,
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we've been finding more and more that crows are really intelligent.
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Their brains are in the same proportion as chimpanzee brains are.
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There's all kinds of anecdotes
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for the different kinds of intelligence they have.
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For example, in Sweden, crows will wait for fishermen
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to drop lines through holes in the ice.
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And when the fishermen move off,
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the crows fly down, reel up the lines, and eat the fish or the bait.
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It's pretty annoying for the fishermen.
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On an entirely different tack,
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at University of Washington a few years ago,
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they were doing an experiment where they captured some crows on campus.
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Some students went out, netted some crows, brought them in,
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weighed and measured them, and let them back out again.
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And they were entertained to discover that for the rest of the week,
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whenever these particular students walked around campus,
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these crows would caw at them and run around,
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and make their life kind of miserable.
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(Laughter)
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They were significantly less entertained
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when this went on for the next week.
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And the next month.
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And after summer break.
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Until they finally graduated and left campus,
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and -- glad to get away, I'm sure --
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came back sometime later, and found the crows still remembered them.
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(Laughter)
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So, the moral being: don't piss off crows.
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So now, students at the University of Washington
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that are studying these crows, do so with a giant wig and a big mask.
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(Laughter)
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It's fairly interesting.
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(Laughter)
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So we know these crows are really smart,
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but the more I dug into this, the more I found
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that they actually have an even more significant adaptation.
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Video: Crows have become highly skilled at making a living
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in these new urban environments.
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In this Japanese city, they have devised a way of eating a food
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that normally they can't manage:
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drop it among the traffic.
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The problem now is collecting the bits, without getting run over.
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Wait for the light to stop the traffic.
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Then, collect your cracked nut in safety.
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(Laughter)
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(Applause)
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Joshua Klein: Yeah, pretty interesting.
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What's significant about this isn't that crows are using cars
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to crack nuts.
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In fact, that's old hat for crows.
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This happened about 10 years ago
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in a place called Sendai City, at a driving school
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in the suburbs of Tokyo.
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And since that time,
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all the crows in the neighborhood are picking up this behavior.
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Now every crow within five kilometers is standing by a sidewalk,
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waiting to collect its lunch.
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So they're learning from each other. And research bears this out.
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Parents seem to be teaching their young.
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They learn from their peers, they learn from their enemies.
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If I have a little extra time,
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I'll tell you about a case of crow infidelity
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that illustrates that nicely.
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The point being, they've developed cultural adaptation.
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And as we heard yesterday,
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that's the Pandora's box that's getting human beings in trouble,
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and we're starting to see it with them.
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They're able to very quickly and very flexibly adapt
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to new challenges and new resources in their environment,
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which is really useful if you live in a city.
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So we know that there's lots of crows.
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We found out they're really smart and they can teach each other.
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When all this became clear,
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I realized the only obvious thing to do is build a vending machine.
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So that's what we did.
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This is a vending machine for crows.
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And it uses Skinnerian training to shape their behavior over four stages.
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It's pretty simple.
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Basically, what happens is that we put this out in a field
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or someplace where there's lots of crows.
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We put coins and peanuts all around the base of the machine.
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Crows eventually come by, eat the peanuts,
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and get used to the machine being there.
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Eventually, they eat all the peanuts.
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Then they see peanuts here on the feeder tray,
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and hop up and help themselves.
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Then they leave, the machine spits up more coins and peanuts,
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and life is dandy if you're a crow --
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you can come back anytime and get yourself a peanut.
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So when they get really used to that, we move on to the crows coming back.
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Now they're used to the sound of the machine;
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they keep coming back and digging out peanuts
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from the pile of coins that's there.
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When they get really happy about this, we stymie them.
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We move to the third stage, where we only give them a coin.
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Now, like most of us who have gotten used to a good thing,
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this really pisses them off.
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So they do what they do in nature when they're looking for something:
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sweep things out of the way with their beak.
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They do that here, and that knocks the coins down the slot.
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When that happens, they get a peanut.
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This goes on for some time.
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The crows learn that all they have to do is show up,
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wait for the coin to come out, put it in the slot,
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then get their peanut.
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When they're good and comfortable with that,
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we move to the final stage, where they show up and nothing happens.
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This is where we see the difference between crows and other animals.
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Squirrels, for example, would show up, look for the peanut, go away.
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Come back, look for the peanut, go away.
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They do this maybe half a dozen times before they get bored,
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and then they go off and play in traffic.
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Crows, on the other hand, show up and they try and figure it out.
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They know this machine has been messing with them
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through three different stages of behavior.
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(Laughter)
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They figure there must be more to it.
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So they poke at it and peck at it.
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And eventually some crow gets a bright idea:
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"Hey, there's lots of coins lying around from the first stage,
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hops down, picks it up, drops it in the slot, and we're off to the races.
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That crow enjoys a temporary monopoly on peanuts,
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until his friends figure out how to do it, and then there we go.
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So, what's significant about this to me
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isn't that we can train crows to pick up peanuts.
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Mind you, there's 216 million dollars' worth of change lost every year,
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but I'm not sure I can depend on that ROI from crows.
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(Laughter)
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Instead, I think we should look a little bit larger.
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I think crows can be trained to do other things.
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For example, why not train them to pick up garbage after stadium events?
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Or find expensive components from discarded electronics?
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Or maybe do search and rescue?
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The main point of all this for me is,
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we can find mutually beneficial systems for these species.
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We can find ways to interact with these other species
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that doesn't involve exterminating them,
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but involves finding an equilibrium with them that's a useful balance.
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Thanks very much.
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(Applause)
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