Joshua Klein: The intelligence of crows

403,966 views ・ 2008-05-19

TED


Please double-click on the English subtitles below to play the video.

00:18
How many of you have seen the Alfred Hitchcock film "The Birds"?
0
18798
3349
00:22
Any of you get really freaked out by that?
1
22171
2016
00:24
You might want to leave now.
2
24868
1383
00:26
(Laughter)
3
26275
1031
00:27
So this is a vending machine for crows.
4
27330
2003
00:29
Over the past few days, many of you have been asking,
5
29357
2493
00:31
"How did you come to this? How did you get started doing this?"
6
31874
2990
00:34
It started, as with many great ideas,
7
34888
1769
00:36
or many ideas you can't get rid of, anyway,
8
36681
2036
00:38
at a cocktail party.
9
38741
1155
00:39
About 10 years ago, I was at a cocktail party with a friend of mine.
10
39920
3210
00:43
We were sitting there, and he was complaining about the crows
11
43154
2889
00:46
that were all over his yard and making a big mess.
12
46067
2371
00:48
And he was telling me we ought to eradicate these things,
13
48462
2702
00:51
kill them, because they're making a mess.
14
51188
1972
00:53
I said that was stupid,
15
53184
1151
00:54
maybe we should just train them to do something useful.
16
54359
2573
00:56
And he said that was impossible.
17
56956
1531
00:58
And I'm sure I'm in good company in finding that tremendously annoying,
18
58511
3372
01:01
when someone tells you it's impossible.
19
61907
1880
01:03
So I spent the next 10 years reading about crows in my spare time.
20
63811
3130
01:06
(Laughter)
21
66965
2776
01:09
And after 10 years of this, my wife said,
22
69765
2197
01:11
"You've got to do this thing you've been talking about,
23
71986
2620
01:14
and build the vending machine."
24
74630
1495
01:16
So I did.
25
76149
1151
01:17
But part of the reason I found this interesting is,
26
77324
2445
01:19
I started noticing that we're very aware of all the species
27
79793
2832
01:22
that are going extinct on the planet
28
82649
1795
01:24
as a result of human habitation expansion,
29
84468
2069
01:26
and no one seems to be paying attention to all the species
30
86561
2945
01:29
that are actually living; they're surviving.
31
89530
2068
01:31
And I'm talking specifically about synanthropic species,
32
91622
2725
01:34
which have adapted specifically for human ecologies,
33
94371
2678
01:37
species like rats and cockroaches and crows.
34
97073
3363
01:40
And as I started looking at them, I was finding that they had hyper-adapted.
35
100460
3614
01:44
They'd become extremely adept at living with us.
36
104098
2392
01:46
And in return, we just tried to kill them all the time.
37
106514
2673
01:49
(Laughter)
38
109211
1095
01:50
And in doing so, we were breeding them for parasitism.
39
110330
2573
01:52
We were giving them all sorts of reasons to adapt new ways.
40
112927
3961
01:56
So, for example, rats are incredibly responsive breeders.
41
116912
2758
01:59
And cockroaches, as anyone who's tried to get rid of them knows,
42
119694
3019
02:02
have become really immune to the poisons that we're using.
43
122737
3002
02:05
So I thought, let's build something that's mutually beneficial;
44
125763
3634
02:09
something that we can both benefit from,
45
129421
1980
02:11
and find some way to make a new relationship with these species.
46
131425
3019
02:14
So I built the vending machine.
47
134468
1642
02:16
But the story of the vending machine is a little more interesting
48
136134
3070
02:19
if you know more about crows.
49
139228
1387
02:20
It turns out, crows aren't just surviving with human beings;
50
140639
2842
02:23
they're actually thriving.
51
143505
1241
02:24
They're found everywhere on the planet except for the Arctic
52
144770
2837
02:27
and the southern tip of South America.
53
147631
1812
02:29
And in all that area, they're only rarely found breeding
54
149467
2691
02:32
more than five kilometers away from human beings.
55
152182
2319
02:34
So we may not think about them, but they're always around.
56
154525
2750
02:37
And not surprisingly, given the human population growth,
57
157299
2644
02:39
more than half of the human population is living in cities now.
58
159967
2976
02:42
And out of those, nine-tenths of the human growth population
59
162967
2815
02:45
is occurring in cities.
60
165806
1158
02:46
We're seeing a population boom with crows.
61
166988
2173
02:49
So bird counts are indicating
62
169185
2045
02:51
that we might be seeing up to exponential growth in their numbers.
63
171254
3148
02:54
So that's no great surprise.
64
174426
1647
02:56
But what was really interesting to me was to find out
65
176097
2493
02:58
that the birds were adapting in a pretty unusual way.
66
178614
2823
03:02
And I'll give you an example of that.
67
182611
1987
03:05
This is Betty. She's a New Caledonian crow.
68
185170
2270
03:07
And these crows use sticks in the wild
69
187464
2406
03:09
to get insects and whatnot out of pieces of wood.
70
189894
2634
03:12
Here, she's trying to get a piece of meat out of a tube.
71
192552
2666
03:15
But the researchers had a problem.
72
195242
1643
03:16
They messed up and left just a stick of wire in there.
73
196909
2548
03:19
And she hadn't had the opportunity to do this before.
74
199481
2523
03:22
You see, it wasn't working very well.
75
202028
1890
03:24
So she adapted.
76
204520
1453
03:27
Now, this is completely unprompted; she had never seen this done before.
77
207117
3403
03:30
No one taught her to bend this into a hook
78
210544
2012
03:32
or had shown her how it could happen.
79
212580
1781
03:34
But she did it all on her own.
80
214385
1453
03:35
So keep in mind -- she's never seen this done.
81
215862
2461
03:38
(Laughter)
82
218347
1591
03:39
Right.
83
219962
1183
03:41
(Laughter)
84
221169
6528
03:47
Yeah. All right.
85
227828
1424
03:49
(Applause)
86
229276
4645
03:53
So that's the part where the researchers freak out.
87
233945
2481
03:56
(Laughter)
88
236450
1769
03:58
It turns out,
89
238243
1167
03:59
we've been finding more and more that crows are really intelligent.
90
239434
3240
04:02
Their brains are in the same proportion as chimpanzee brains are.
91
242698
3582
04:06
There's all kinds of anecdotes
92
246954
1442
04:08
for the different kinds of intelligence they have.
93
248420
2362
04:10
For example, in Sweden, crows will wait for fishermen
94
250806
2500
04:13
to drop lines through holes in the ice.
95
253330
1893
04:15
And when the fishermen move off,
96
255247
1540
04:16
the crows fly down, reel up the lines, and eat the fish or the bait.
97
256811
3241
04:20
It's pretty annoying for the fishermen.
98
260076
1938
04:22
On an entirely different tack,
99
262038
1439
04:23
at University of Washington a few years ago,
100
263501
2590
04:26
they were doing an experiment where they captured some crows on campus.
101
266115
3360
04:29
Some students went out, netted some crows, brought them in,
102
269499
2818
04:32
weighed and measured them, and let them back out again.
103
272341
2584
04:34
And they were entertained to discover that for the rest of the week,
104
274949
3212
04:38
whenever these particular students walked around campus,
105
278185
2632
04:40
these crows would caw at them and run around,
106
280841
2111
04:42
and make their life kind of miserable.
107
282976
1812
04:44
(Laughter)
108
284812
1002
04:45
They were significantly less entertained
109
285838
1945
04:47
when this went on for the next week.
110
287807
1729
04:49
And the next month.
111
289560
1273
04:50
And after summer break.
112
290857
1728
04:52
Until they finally graduated and left campus,
113
292609
2299
04:54
and -- glad to get away, I'm sure --
114
294932
1740
04:56
came back sometime later, and found the crows still remembered them.
115
296696
3239
04:59
(Laughter)
116
299959
1006
05:00
So, the moral being: don't piss off crows.
117
300989
2075
05:03
So now, students at the University of Washington
118
303088
3219
05:06
that are studying these crows, do so with a giant wig and a big mask.
119
306331
3372
05:09
(Laughter)
120
309727
2215
05:11
It's fairly interesting.
121
311966
1310
05:13
(Laughter)
122
313300
1571
05:14
So we know these crows are really smart,
123
314895
1924
05:16
but the more I dug into this, the more I found
124
316843
2180
05:19
that they actually have an even more significant adaptation.
125
319047
3165
05:23
Video: Crows have become highly skilled at making a living
126
323276
3414
05:26
in these new urban environments.
127
326714
2347
05:29
In this Japanese city, they have devised a way of eating a food
128
329085
3911
05:33
that normally they can't manage:
129
333020
2287
05:37
drop it among the traffic.
130
337623
1810
05:43
The problem now is collecting the bits, without getting run over.
131
343633
5141
05:48
Wait for the light to stop the traffic.
132
348798
2301
06:02
Then, collect your cracked nut in safety.
133
362939
3466
06:10
(Laughter)
134
370032
1274
06:11
(Applause)
135
371330
1079
06:12
Joshua Klein: Yeah, pretty interesting.
136
372433
1993
06:14
What's significant about this isn't that crows are using cars
137
374450
2937
06:17
to crack nuts.
138
377411
1151
06:18
In fact, that's old hat for crows.
139
378586
1641
06:20
This happened about 10 years ago
140
380251
1535
06:21
in a place called Sendai City, at a driving school
141
381810
2527
06:24
in the suburbs of Tokyo.
142
384361
1161
06:26
And since that time,
143
386067
1155
06:27
all the crows in the neighborhood are picking up this behavior.
144
387246
3062
06:30
Now every crow within five kilometers is standing by a sidewalk,
145
390332
3027
06:33
waiting to collect its lunch.
146
393383
1413
06:35
So they're learning from each other. And research bears this out.
147
395321
3070
06:38
Parents seem to be teaching their young.
148
398415
2514
06:40
They learn from their peers, they learn from their enemies.
149
400953
2850
06:43
If I have a little extra time,
150
403827
1455
06:45
I'll tell you about a case of crow infidelity
151
405306
2147
06:47
that illustrates that nicely.
152
407477
1438
06:49
The point being, they've developed cultural adaptation.
153
409342
2668
06:52
And as we heard yesterday,
154
412034
1245
06:53
that's the Pandora's box that's getting human beings in trouble,
155
413303
3042
06:56
and we're starting to see it with them.
156
416369
1873
06:58
They're able to very quickly and very flexibly adapt
157
418266
2536
07:00
to new challenges and new resources in their environment,
158
420826
2728
07:03
which is really useful if you live in a city.
159
423578
2245
07:07
So we know that there's lots of crows.
160
427011
2082
07:09
We found out they're really smart and they can teach each other.
161
429117
3061
07:12
When all this became clear,
162
432202
1301
07:13
I realized the only obvious thing to do is build a vending machine.
163
433527
3163
07:16
So that's what we did.
164
436714
1153
07:17
This is a vending machine for crows.
165
437891
1737
07:19
And it uses Skinnerian training to shape their behavior over four stages.
166
439652
3667
07:23
It's pretty simple.
167
443343
1357
07:24
Basically, what happens is that we put this out in a field
168
444724
3004
07:27
or someplace where there's lots of crows.
169
447752
1970
07:29
We put coins and peanuts all around the base of the machine.
170
449746
2837
07:32
Crows eventually come by, eat the peanuts,
171
452607
2041
07:34
and get used to the machine being there.
172
454672
1934
07:36
Eventually, they eat all the peanuts.
173
456630
1781
07:38
Then they see peanuts here on the feeder tray,
174
458435
2319
07:40
and hop up and help themselves.
175
460778
1722
07:42
Then they leave, the machine spits up more coins and peanuts,
176
462524
2873
07:45
and life is dandy if you're a crow --
177
465421
1770
07:47
you can come back anytime and get yourself a peanut.
178
467215
2446
07:49
So when they get really used to that, we move on to the crows coming back.
179
469685
3485
07:53
Now they're used to the sound of the machine;
180
473194
2103
07:55
they keep coming back and digging out peanuts
181
475321
2112
07:57
from the pile of coins that's there.
182
477457
1723
07:59
When they get really happy about this, we stymie them.
183
479204
2536
08:01
We move to the third stage, where we only give them a coin.
184
481764
2794
08:04
Now, like most of us who have gotten used to a good thing,
185
484582
2738
08:07
this really pisses them off.
186
487344
1339
08:08
So they do what they do in nature when they're looking for something:
187
488707
3280
08:12
sweep things out of the way with their beak.
188
492011
2073
08:14
They do that here, and that knocks the coins down the slot.
189
494108
2842
08:16
When that happens, they get a peanut.
190
496974
1786
08:18
This goes on for some time.
191
498784
1295
08:20
The crows learn that all they have to do is show up,
192
500103
2436
08:22
wait for the coin to come out, put it in the slot,
193
502563
2350
08:24
then get their peanut.
194
504937
1151
08:26
When they're good and comfortable with that,
195
506112
2079
08:28
we move to the final stage, where they show up and nothing happens.
196
508215
3171
08:31
This is where we see the difference between crows and other animals.
197
511410
3207
08:34
Squirrels, for example, would show up, look for the peanut, go away.
198
514641
3712
08:38
Come back, look for the peanut, go away.
199
518377
2554
08:40
They do this maybe half a dozen times before they get bored,
200
520955
2838
08:43
and then they go off and play in traffic.
201
523817
1977
08:45
Crows, on the other hand, show up and they try and figure it out.
202
525818
3648
08:49
They know this machine has been messing with them
203
529490
2305
08:51
through three different stages of behavior.
204
531819
2022
08:53
(Laughter)
205
533865
1002
08:54
They figure there must be more to it.
206
534891
1779
08:56
So they poke at it and peck at it.
207
536694
1809
08:58
And eventually some crow gets a bright idea:
208
538527
2154
09:00
"Hey, there's lots of coins lying around from the first stage,
209
540705
3921
09:04
hops down, picks it up, drops it in the slot, and we're off to the races.
210
544650
4165
09:08
That crow enjoys a temporary monopoly on peanuts,
211
548839
2420
09:11
until his friends figure out how to do it, and then there we go.
212
551283
3643
09:14
So, what's significant about this to me
213
554950
2356
09:17
isn't that we can train crows to pick up peanuts.
214
557330
2334
09:19
Mind you, there's 216 million dollars' worth of change lost every year,
215
559688
3830
09:23
but I'm not sure I can depend on that ROI from crows.
216
563542
2655
09:26
(Laughter)
217
566221
1047
09:27
Instead, I think we should look a little bit larger.
218
567292
3184
09:30
I think crows can be trained to do other things.
219
570500
2266
09:32
For example, why not train them to pick up garbage after stadium events?
220
572790
3476
09:36
Or find expensive components from discarded electronics?
221
576290
2904
09:39
Or maybe do search and rescue?
222
579218
1885
09:41
The main point of all this for me is,
223
581679
2627
09:44
we can find mutually beneficial systems for these species.
224
584330
2729
09:47
We can find ways to interact with these other species
225
587083
2504
09:49
that doesn't involve exterminating them,
226
589611
1934
09:51
but involves finding an equilibrium with them that's a useful balance.
227
591569
3302
09:54
Thanks very much.
228
594895
1255
09:56
(Applause)
229
596174
5600
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7