11:34
TED2008

Joshua Klein: A thought experiment on the intelligence of crows

ジョシュア・クライン: カラスの知性

Filmed:

ハッカーであり作家でもあるジョシュア・クラインは、カラスに魅了されています(彼らのつぶらな瞳に浮かぶ、知的な輝きに気づいたことはありますか?)。アマチュアながらも長年に及ぶカラス科の研究の結果、彼は人と動物の新しい絆となり得る、小さな機械を思いつきます。

- Hacker
Joshua Klein is a fervent hacker of all things, including wet, pulpy systems like animals and people and the way they behave. Full bio

How many of you have seen the Alfred Hitchcock film "The Birds"?
ヒッチコック監督の映画 「鳥」は見ましたか?
00:18
Any of you get really freaked out by that?
あまりの怖さに発狂した人は?
00:21
You might want to leave now.
席を外された方が...
00:24
(Laughter)
(笑)
00:26
So, this is a vending machine for crows.
これはカラスのための自動販売機です
00:27
And over the past few days, many of you have been asking me,
最近良く聞かれるんですよ
00:29
"How did you come to this? How did you get started doing this?"
”なんでこうなった?”ってね
00:31
And it started, as with many great ideas,
素晴らしいアイデアとは いつも
00:34
or many ideas you can't get rid of anyway,
まあそれほど素晴らしくなくとも
00:36
at a cocktail party.
カクテルパーティで生まれるものです
00:38
About 10 years ago, I was at a cocktail party with a friend of mine,
10年ほど前 カクテルパーティで友達が
00:39
and we're sitting there, and he was complaining about the crows
カラスが庭を荒らしまわると
00:42
that he had seen that were all over his yard and making a big mess.
カラスの文句を言い出しました
00:44
And he was telling me that really, we ought to try and eradicate these things.
絶滅させるべきだと言うんです
00:48
We gotta kill them because they're making a mess.
退治しなきゃ と言う彼に 僕は
00:50
I said that was stupid,
馬鹿げてる と言いました
00:52
you know, maybe we should just train them to do something useful.
調教したら?と提案すると
00:53
And he said that was impossible.
そんなの無理だろって言うんですね
00:55
And I'm sure I'm in good company in finding that tremendously annoying
僕は誰かが「無理だ」と言うと
00:58
-- when someone tells you it's impossible.
妙にムカついちゃって
01:01
So, I spent the next 10 years reading about crows in my spare time.
その後10年間 空いた時間はカラスの勉強に費やしました
01:02
(Laughter)
(笑)
01:06
And after 10 years of this, my wife eventually said,
10年経って 妻が言いました
01:09
"Look, you know, you gotta do this thing
「ずっと言い続けてた
01:11
you've been talking about, and build the vending machine."
自動販売機を作ってみたら?」ってね
01:13
So I did.
それで実行しました
01:15
But part of the reason that I found this interesting
興味深いのは
01:16
is that I started noticing that we are
人間の居住地拡大に伴って
01:18
very aware of all the species that are going
絶滅しそうな種の存在には
01:20
extinct on the planet as a result of human habitation expansion,
敏感な私たちですが
01:22
and no one seems to be paying attention
今現在「生き残っている」種に対しては
01:24
to all the species that are actually living -- that are surviving.
無関心だという点です
01:27
And I'm talking specifically about synanthropic species,
特に 「共ヒト生」の種についてはそうです
01:30
which are species that have adapted specifically for human ecologies,
人間の生活環境に適合してきた動物たちです
01:33
species like rats and cockroaches and crows.
ネズミやゴキブリ カラスなどですね
01:36
And as I started looking at them, I was finding that they had hyper-adapted.
彼らの適応力には目を見張ります
01:40
They'd become extremely adept at living with us.
人類と共に生きられるよう進化したんです
01:43
And in return, we just tried to kill them all the time.
それに引き替え 私たちは殺そうとするばかり
01:46
And in doing so, we were breeding them for parasitism.
それが なおさら彼らを「寄生」させています
01:50
We were giving them all sorts of reasons to adapt new ways.
適合するしかない状況を作っているのです
01:52
So, for example, rats are incredibly responsive breeders.
ネズミは凄い速さで増えますし
01:56
And cockroaches, as anyone who's tried to get rid of them knows,
退治した経験のある方ならご存じのように
01:59
have become really immune to the poisons that we're using.
ゴキブリは殺虫剤に強くなりました
02:02
So, I thought, let's build something that's mutually beneficial.
双方に有益な道はないのか考えたんです
02:05
Well, then let's build something that we can both benefit from,
お互いに利益を得られるものを考えてみようと
02:08
and find some way to make a new relationship with these species.
新しい関係を模索しようと考えました
02:10
And so I built the vending machine.
そしてこの機械なんですね
02:13
But the story of the vending machine is a little more interesting
その前に カラスについて少し
02:16
if you know more about crows.
お話ししましょう
02:18
It turns out that crows aren't just surviving with human beings --
彼らはかろうじて生き延びている訳ではなく
02:20
they're actually really thriving.
実際はとても繁栄しています
02:22
They're found everywhere on the planet except for the Arctic
北極と南米大陸の最南端を除いた
02:24
and the southern tip of South America.
あらゆる場所に生息していて
02:26
And in all that area, they're only rarely found
そのほとんどが 人間の居住地から
02:28
breeding more than five kilometers away from human beings.
5キロ以内に住んでいます
02:31
So we may not think about them,
私たちは気にしませんが
02:33
but they're always around.
彼らはいつも側にいるのです
02:35
And not surprisingly, given the human population growth,
人類の人口増加を考えれば-
02:37
more than half of the human population is living in cities now.
全人口の過半数は都市部に住んでいて
02:39
And out of those, nine-tenths
人口増加の9割が
02:42
of the human growth population is occurring in cities.
都市部で起きているのですが-
02:44
We're seeing a population boom with crows.
カラスも共に人口爆発しているのです
02:46
So bird counts are indicating that we might be seeing
私たちは彼らの急激な増殖に
02:49
up to exponential growth in their numbers.
立ち会っているのかも知れません
02:51
So that's no great surprise.
でもそれ以上に
02:53
But what was really interesting to me was to find out that
本当に興味深いのは
02:56
the birds were adapting in a pretty unusual way.
彼らの適応能力です
02:58
And I'll give you an example of that.
例をお見せしましょう
03:01
So this is Betty. She's a New Caledonian crow.
カレドニアガラスのベティです
03:04
And these crows use sticks in the wild
この種のカラスは小枝を使って
03:07
to get insects and whatnot out of pieces of wood.
木からエサを捕る習性があります
03:09
Here, she's trying to get a piece of meat out of a tube.
今もエサを捕ろうとしていますが
03:12
But the researchers had a problem.
研究員がミスをしました
03:14
They messed up and left just a stick of wire in there.
ただの針金を与えてしまったのです
03:16
And she hadn't had the opportunity to do this before.
彼女はこんな経験は初めてです
03:18
You see, it wasn't working very well.
うまくいかないようですね
03:21
So she adapted.
でも彼女は適応するんです
03:24
Now this is completely unprompted. She had never seen this done before.
これは完全に自発的な行動です 見た事もありません
03:26
No one taught her to bend this into a hook,
曲げてフックにするなんて
03:30
had shown her how it could happen.
誰も教えてないんです
03:32
But she did it all on her own.
でも自分で発見するんです
03:33
So keep in mind that she's never seen this done.
見た事がないにも関わらずです
03:35
Right.
そうそう
03:39
(Laughter)
(笑)
03:41
Yeah. All right.
はい 良くできました
03:48
(Applause)
(拍手)
03:50
That's the part where the researchers freak out.
研究員が発狂した場面です
03:53
(Laughter)
(笑)
03:56
So, it turns out we've been finding more and more
カラスは本当に賢いことが
03:58
that crows are really, really intelligent.
明らかになってきています
04:00
Their brains are proportionate,
脳の大きさの比率は
04:01
in the same proportion as chimpanzee brains are.
チンパンジーのそれと同等です
04:02
There are all kinds of anecdotes for different kinds of intelligence they have.
彼らの知恵の数だけ逸話もあります
04:05
For example, in Sweden,
スウェーデンでは
04:09
crows will wait for fishermen to drop lines through holes in the ice.
釣り人が氷の穴に糸を垂らすのを待ち
04:11
And when the fishermen move off,
釣り人が場を離れると
04:13
the crows fly down, reel up the lines, and eat the fish or the bait.
糸を引き上げ 魚や釣り餌を食べるのです
04:15
It's pretty annoying for the fishermen.
釣り人にとってはいい迷惑です
04:19
On an entirely different tack,
別の話になりますが
04:22
at University of Washington, they, a few years ago,
数年前 ワシントン大学で
04:23
were doing an experiment where they captured some crows on campus.
学生が研究のために カラスを捕まえていました
04:25
Some students went out and netted some crows,
何人かの学生がカラスを捕獲して
04:28
brought them in, and were -- weighed them, and measured them and whatnot,
体重を量ったりいろいろしてたんです
04:30
and then let them back out again.
調査が終わると放します
04:33
And were entertained to discover
面白い事に
04:34
that for the rest of the week, these crows,
その週の間 カラスたちは
04:35
whenever these particular students walked around campus,
自分を捕まえた学生が現れる度に
04:37
these crows would caw at them,
彼らに向かってカーカー鳴いたり
04:39
and run around and make their life kind of miserable.
歩き回ったりして からかうんです
04:41
They were significantly less entertained when this went on for the next week.
こんな状態が翌月も 夏休みが明けても
04:44
And the next month. And after summer break.
まだ続いたので 笑ってもいられなくなりました
04:48
Until they finally graduated and left campus,
結局 卒業するまで続きました
04:52
and -- glad to get away, I'm sure --
さぞ嬉しかったでしょうね
04:54
came back sometime later, and found the crows still remembered them.
でも卒業後もなお 彼らを覚えているんです
04:56
So -- the moral being, don't piss off crows.
カラスを怒らせると罰が当たりますよ
04:59
So now, students at the University of Washington
今では カラスについて
05:02
that are studying these crows
研究する学生達は
05:06
do so with a giant wig and a big mask.
カツラと覆面をかぶるんですよ
05:07
(Laughter)
(笑)
05:09
It's fairly interesting.
興味深いですね
05:12
So we know that these crows are really smart,
カラスは本当に賢いんです
05:14
but the more I dug into this, the more I found
でも 調べれば調べるほど
05:16
that they actually have an even more significant adaptation.
さらに高度な適応能力を発見しました
05:18
Video: Crows have become highly skilled at
ビデオ: カラスは都会の環境の中で
05:23
making a living in these new urban environments.
巧みに生きるすべを見つけています
05:25
In this Japanese city, they have devised a way of
この日本のカラスは 堅い木の実を
05:29
eating a food that normally they can't manage:
食べる方法を発見しました
05:32
drop it among the traffic.
車に轢いてもらうのです
05:37
The problem now is collecting the bits,
でも 自分が轢かれることなく拾うには
05:43
without getting run over.
どうすれば良いでしょうか
05:46
Wait for the light to stop the traffic.
信号が変わるのを待ちましょう
05:48
Then, collect your cracked nut in safety.
そうすれば安全に拾えますね
06:02
(Laughter)
(笑)
06:10
(Applause)
(拍手)
06:11
Joshua Klein: Yeah, yeah. Pretty interesting.
はい なかなか面白いですね
06:12
So what's significant about this isn't that crows are using cars to crack nuts.
ポイントは 車を使って木の実を割るところではありません
06:14
In fact, that's old hat for crows.
これはカラスには朝飯前なのです
06:17
This happened about 10 years ago
10年ほど前に
06:19
in a place called Sendai City, at a driving school
仙台にある
06:21
in the suburbs of Tokyo.
自動車学校で起こりました
06:24
And since that time,
それからというもの
06:26
all of the crows in the neighborhood are picking up this behavior.
近隣のカラスがマネをするようになりました
06:27
And now, every crow within five kilometers is standing by a sidewalk,
今ではこの辺りのカラスは お昼を食べようと
06:29
waiting to collect its lunch.
みんな歩道で待ち構えています
06:32
So, they're learning from each other. And research bears this out.
彼らは互いに学習することが実証されています
06:35
Parents seem to be teaching their young.
親は子供を教育しますし
06:37
They've learned from their peers. They've learned from their enemies.
仲間から学習し 敵からも学びます
06:39
If I have a little extra time, I'll tell you about a case of crow infidelity
時間があれば これを象徴するカラスの裏切りについて
06:43
that illustrates that nicely.
お話するんですけどね
06:46
The point being that they've developed cultural adaptation.
彼らは文化的適応を修得したんです
06:48
And as we heard yesterday,
昨日の講演で聞いたように
06:51
that's the Pandora's box that's getting human beings in trouble,
これは人類を苦しめるパンドラの箱かも知れません
06:53
and we're starting to see it with them.
カラスにそれを見ているのです
06:55
They're able to very quickly and very flexibly adapt
彼らは環境や資源の変化に
06:57
to new challenges and new resources in their environment,
迅速に 柔軟に適応することが可能です
07:00
which is really useful if you live in a city.
都会に住むには好都合でしょう
07:03
So we know that there's lots of crows.
さて カラスがどこにでも存在し
07:06
We found out they're really smart, and we found out that they can teach each other.
頭が良く 互いに学習することが分かりました
07:08
And when all this became clear to me,
これらの事実が明確になったので
07:11
I realized the only obvious thing to do is build a vending machine.
自動販売機を作ろうと思い立ったんです
07:13
So that's what we did.
これがそうです
07:16
This is a vending machine for crows.
カラスのための自販機です
07:17
And it uses Skinnerian training to shape their behavior over four stages.
スキナー理論を使い 4つの段階に分けて学習させます
07:19
It's pretty simple.
とても単純です
07:22
Basically, what happens is that we put this out in a field,
まず この機械を野原やどこかの
07:24
or someplace where there's lots of crows,
カラスがいる場所に設置します
07:27
and we put coins and peanuts all around the base of the machine.
そしてコインとエサを周りにばらまきます
07:29
And crows eventually come by, and eat the peanuts
彼らはエサを食べに来るようになり
07:31
and get used to the machine being there.
機械の存在にも慣れ
07:33
And eventually, they eat up all the peanuts.
やがて落ちているエサを食べ尽くします
07:35
And then they see that there are peanuts here on the feeder tray,
機械のトレイにまだエサがあるのを見ると
07:37
and they hop up and help themselves.
飛び乗って食べるようになります
07:40
And then they leave, and the machine spits up more coins and peanuts,
彼らが去ったら 更にコインとエサをばらまきます
07:42
and life is really dandy, if you're a crow.
カラスにとっては夢のようです
07:44
Then you can come back anytime and get yourself a peanut.
ここに来れば食事にありつけるのです
07:46
So, when they get really used to that, we move on to the crows coming back.
次の段階では 常連になったカラスに着目します
07:49
Now, they're used to the sound of the machine, and they keep coming back,
彼らは機械の騒音にも慣れ 何度も戻ってきては
07:52
and digging out these peanuts from amongst the pile of coins that's there.
コインの山からエサを探すのも苦にしません
07:55
And when they get really happy about this,
彼らが幸せを享受しだしたら
07:57
we go ahead and stymie them.
苦難を授けます
07:59
And we move to the third stage, where we only give them a coin.
3つ目の段階では コインしか与えません
08:01
Now, like most of us who have gotten used to a good thing,
楽な生活に慣れた人間と同様に
08:04
this really pisses them off.
カラスも腹を立てます
08:06
So, they do what they do in nature when they're looking for something --
物を探すときに本能的にやるように
08:07
they sweep things out of the way with their beak.
くちばしで辺りを掃き散らかします
08:11
And they do that here, and that knocks the coins down the slot,
そして偶然にもコインがスロットに入ると
08:13
and when that happens, they get a peanut.
エサが出てきます
08:16
And so this goes on for some time.
しばらくこれを続けます
08:18
The crows learn that all they have to do is show up,
やがて彼らはコインが出てくるのを待ち
08:19
wait for the coin to come out, put the coin in the slot, and then they get their peanut.
スロットに入れればエサが出ることを学びます
08:21
And when they're really good and comfortable with that,
この日常に慣れてきたら
08:24
we move to the final stage, in which they show up and nothing happens.
「何も起きない」 という最終ステージに進みます
08:26
And this is where we see the difference between crows and other animals.
カラスが他の動物との違いを見せるところです
08:31
Squirrels, for example, would show up, look for the peanut, go away.
リスの場合 エサがなければ去っていきます
08:33
Come back, look for the peanut, go away.
また探しに来ますが すぐ諦めます
08:37
They do this maybe half a dozen times before they get bored,
これを数回繰り返して 飽きてしまいます
08:40
and then they go off and play in traffic.
そして道路に飛び出すんです
08:43
Crows, on the other hand, show up, and they try and figure it out.
カラスの場合は 問題を解決しようとします
08:45
They know that this machine's been messing with them,
彼らは この機械が3つの段階を経て
08:49
through three different stages of behavior.
自分たちをもてあそんで来た事を知っています
08:51
(Laughter)
(笑)
08:53
They figure it's gotta have more to it.
まだ何かあると考えるんですね
08:54
So, they poke at it and peck at it and whatnot.
なので 押したり突いたりするんです
08:56
And eventually some crow gets a bright idea that,
やがて彼らはひらめきます
08:58
"Hey, there's lots of coins lying around from the first stage,
「ステージ1で使ったコインがたくさん落ちてるぞ」
09:00
lying around on the ground," hops down, picks it up, drops it in the slot.
地上のコインを拾い スロットに投入します
09:03
And then, we're off to the races.
ここまで来たら話は早いです
09:06
That crow enjoys a temporary monopoly on peanuts,
そのカラスは一時的にエサを独占できますが
09:08
until his friends figure out how to do it, and then there we go.
それも周りが気づくまでです
09:10
So, what's significant about this to me
僕にとって重要なのは
09:15
isn't that we can train crows to pick up peanuts.
カラスで稼げるという事ではありません
09:17
Mind you, there's 216 million dollars' worth of change lost every year,
私たちは毎年2億ドルの小銭を紛失していますが
09:19
but I'm not sure I can depend on that ROI from crows.
カラスにそこまでの投資利益率は求められません
09:23
Instead, I think we should look a little bit larger.
ですが より大きく考えてはどうでしょう
09:27
I think that crows can be trained to do other things.
カラスは他の事にも訓練できると思うのです
09:30
For example, why not train them to pick up garbage after stadium events?
競技場でゴミを拾わせるとか
09:32
Or find expensive components from discarded electronics?
廃棄物から 高価なパーツを探させるとか
09:36
Or maybe do search and rescue?
遭難者の探索などです
09:38
The main thing, the main point of all this for me is
この話のポイントは
09:40
that we can find mutually beneficial systems for these species.
共に有益な社会は構築可能だということです
09:44
We can find ways to interact with these other species
彼らと共生していく方法-
09:46
that doesn't involve exterminating them,
彼らを駆逐するのではなく
09:48
but involves finding an equilibrium with them that's a useful balance.
共に助け合う バランスの取れた関係はなし得るのです
09:50
Thanks very much.
ありがとうございました
09:54
(Applause)
(拍手)
09:56
Translated by Satoru Arao
Reviewed by Takako Sato

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About the Speaker:

Joshua Klein - Hacker
Joshua Klein is a fervent hacker of all things, including wet, pulpy systems like animals and people and the way they behave.

Why you should listen

Joshua Klein will hack anything that moves -- his list includes "social systems, computer networks, institutions, consumer hardware and animal behavior." His latest project, though charmingly low-tech, has amazing implications for the human-animal interface.

Right now, Klein is working at Frog Design as a Principle Technologist, while developing mobile/social applications, health care-related systems and other tools that improve people's lives. He's the author of the novel Roo'd, which was the first modern book (after Tarzan) to be ported to the iPhone.

More profile about the speaker
Joshua Klein | Speaker | TED.com