Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:03,400 --> 00:00:05,360
LOW PEEPING
2
00:00:07,520 --> 00:00:10,360
SHARP CHIRPING
3
00:00:10,360 --> 00:00:13,720
LILTING SONG
4
00:00:13,720 --> 00:00:15,760
LOW, BABBLING CALL
5
00:00:15,760 --> 00:00:18,000
HIGH, REPEATING CALL
6
00:00:18,000 --> 00:00:19,920
CHATTERING SONG
7
00:00:19,920 --> 00:00:27,920
DAWN CHORUS BUILDS
8
00:00:29,960 --> 00:00:32,320
SHRILL, WHIRLING CALL
9
00:00:32,320 --> 00:00:38,400
On a clear spring morning like this,
the dawn chorus is at its peak.
10
00:00:38,400 --> 00:00:40,840
DAWN CHORUS CONTINUES
11
00:00:40,840 --> 00:00:45,760
There are surely few more enchanting
natural soundscapes than this.
12
00:00:45,760 --> 00:00:49,320
DAWN CHORUS CONTINUES
13
00:00:49,320 --> 00:00:54,000
But this avian choir
does not sing for us.
14
00:00:58,440 --> 00:01:03,000
These are songs of seduction
and weapons of war.
15
00:01:04,280 --> 00:01:08,480
Males are defending territories
and attracting mates.
16
00:01:08,480 --> 00:01:10,640
LOW CHIRPING
17
00:01:10,640 --> 00:01:12,040
COOING
18
00:01:12,040 --> 00:01:14,160
Singing is dangerous.
19
00:01:14,160 --> 00:01:15,280
CUCKOO!
20
00:01:15,280 --> 00:01:16,480
HIGH, CHATTERING SONG
21
00:01:16,480 --> 00:01:19,320
It reveals the bird's
location to predators.
22
00:01:20,680 --> 00:01:23,720
But it also offers a huge reward -
23
00:01:23,720 --> 00:01:25,760
the chance to attract a female and
24
00:01:25,760 --> 00:01:29,080
pass on genes
to the next generation.
25
00:01:29,080 --> 00:01:32,840
That, Charles Darwin said,
is why song evolved.
26
00:01:34,800 --> 00:01:38,280
It was an example
of what he called sexual selection.
27
00:01:41,720 --> 00:01:46,920
But, today, new discoveries are
transforming those long-held ideas.
28
00:01:49,080 --> 00:01:50,280
For this programme,
29
00:01:50,280 --> 00:01:54,160
I've chosen some of my favourite
recordings from the natural world
30
00:01:54,160 --> 00:01:57,440
that have revolutionised
our understanding of song.
31
00:02:00,040 --> 00:02:02,360
There are seven recordings of it
32
00:02:02,360 --> 00:02:05,760
that have particular interest
for me.
33
00:02:05,760 --> 00:02:07,360
Some are lovely,
34
00:02:07,360 --> 00:02:09,200
some are surprising,
35
00:02:09,200 --> 00:02:11,800
and one almost broke my heart.
36
00:02:11,800 --> 00:02:14,400
But all of them broke new ground.
37
00:02:14,400 --> 00:02:20,880
ANIMALS SING
38
00:02:24,920 --> 00:02:28,680
BIRDSONG, INSECTS BUZZING
39
00:02:30,600 --> 00:02:34,120
I've recorded many sounds of
the natural world over the years...
40
00:02:35,840 --> 00:02:38,720
..and I've learned that there is,
perhaps surprisingly,
41
00:02:38,720 --> 00:02:41,440
no scientific definition of song.
42
00:02:43,840 --> 00:02:45,360
We tend to use the word
43
00:02:45,360 --> 00:02:48,960
to describe sounds that seem,
to our ears, beautiful.
44
00:02:48,960 --> 00:02:51,520
TUNEFUL WHISTLING
45
00:02:53,960 --> 00:02:58,280
It is, in truth,
a somewhat whimsical label,
46
00:02:58,280 --> 00:03:02,120
but it has been attached to
some of nature's greatest marvels.
47
00:03:02,120 --> 00:03:04,640
Just listen to this.
48
00:03:04,640 --> 00:03:09,480
WHALE SONG
49
00:03:19,840 --> 00:03:25,160
Each of my seven chosen songs
was recorded in my lifetime.
50
00:03:26,400 --> 00:03:27,880
BOUNCING CHIRP
51
00:03:27,880 --> 00:03:31,240
The oldest was made when I was five.
52
00:03:31,240 --> 00:03:33,840
The most recent,
just a few years ago.
53
00:03:33,840 --> 00:03:37,480
CHATTERING SONG
54
00:03:37,480 --> 00:03:40,440
None is closer to my heart than
the first one...
55
00:03:40,440 --> 00:03:41,880
HONKING CALLS
56
00:03:41,880 --> 00:03:44,960
..which I made back in 1960.
57
00:03:44,960 --> 00:03:46,200
HE CHUCKLES
58
00:03:46,200 --> 00:03:51,280
WHOOPING CALLS
59
00:03:59,600 --> 00:04:03,000
Recording audio in the field
in remote parts of the world
60
00:04:03,000 --> 00:04:05,440
was almost unheard of.
61
00:04:05,440 --> 00:04:10,480
There was certainly no money in the
BBC budget for a sound recordist,
62
00:04:10,480 --> 00:04:14,000
but I did manage to get hold
of a very rare thing indeed -
63
00:04:14,000 --> 00:04:17,160
a battery-driven portable
tape recorder -
64
00:04:17,160 --> 00:04:19,680
so that I could
record sounds myself.
65
00:04:22,240 --> 00:04:26,360
It was a cumbersome piece of kit,
but cutting-edge at the time,
66
00:04:26,360 --> 00:04:29,560
and I was determined to use it
to record a singer
67
00:04:29,560 --> 00:04:32,040
that no-one
had ever recorded before.
68
00:04:33,160 --> 00:04:36,480
Madagascar's largest lemur,
the indri.
69
00:04:39,160 --> 00:04:41,920
EERIE WHOOPING CALLS
70
00:04:41,920 --> 00:04:44,400
PAST ATTENBOROUGH: This noise
was no bird call.
71
00:04:44,400 --> 00:04:46,840
I had never heard anything
like it before.
72
00:04:46,840 --> 00:04:48,800
It must be the voice of the indris.
73
00:04:48,800 --> 00:04:53,200
CALLS CONTINUE
74
00:04:53,200 --> 00:04:55,520
PRESENT ATTENBOROUGH:
Using my new equipment,
75
00:04:55,520 --> 00:04:58,920
I made the first-ever
audio recording of the indri.
76
00:04:58,920 --> 00:05:02,320
CALLS CONTINUE
77
00:05:05,920 --> 00:05:09,400
But could we also capture them
on camera as well?
78
00:05:11,040 --> 00:05:14,160
PAST: The song was
so loud that it seemed impossible
79
00:05:14,160 --> 00:05:17,560
that the animals could be
more than 20 or 30 yards away,
80
00:05:17,560 --> 00:05:19,080
but where were they?
81
00:05:19,080 --> 00:05:21,760
CALLS CONTINUE
82
00:05:21,760 --> 00:05:24,520
PRESENT: Until now,
no-one had even managed
83
00:05:24,520 --> 00:05:28,560
to photograph a living one,
let alone film it.
84
00:05:28,560 --> 00:05:31,200
PAST: Infuriatingly,
the bush was so thick
85
00:05:31,200 --> 00:05:33,720
that I could see no sign of them,
whatever.
86
00:05:33,720 --> 00:05:36,240
CALLS CONTINUE
87
00:05:36,240 --> 00:05:39,960
So the question was,
how could we get close enough
88
00:05:39,960 --> 00:05:42,640
to get a clear view of them
without frightening them?
89
00:05:44,040 --> 00:05:47,360
"Well," I thought, "what about
doing it the other way around
90
00:05:47,360 --> 00:05:51,560
"and trying to persuade them
to get closer to us
91
00:05:51,560 --> 00:05:53,920
"by playing their calls?"
92
00:05:58,760 --> 00:06:02,480
RECORDING OF INDRI CALLS PLAYS
93
00:06:02,480 --> 00:06:05,920
And they did
exactly what I hoped they would do.
94
00:06:05,920 --> 00:06:11,080
RECORDING CONTINUES
95
00:06:11,080 --> 00:06:15,200
NEARBY CALLS
96
00:06:15,200 --> 00:06:18,400
They called in return,
came down close to us,
97
00:06:18,400 --> 00:06:20,480
stared at us, still calling.
98
00:06:20,480 --> 00:06:23,520
INDRIS CALL
99
00:06:26,720 --> 00:06:29,160
PRESENT: I was thrilled -
100
00:06:29,160 --> 00:06:32,960
we had recorded their song
and filmed them singing.
101
00:06:35,920 --> 00:06:38,600
But why had this trick worked?
102
00:06:38,600 --> 00:06:41,520
INDRI CALL
103
00:06:44,040 --> 00:06:46,920
Well, because they thought
that the song I was playing
104
00:06:46,920 --> 00:06:50,080
meant a competitor was close by,
105
00:06:50,080 --> 00:06:52,640
and their response was to sing.
106
00:06:55,720 --> 00:06:59,520
And this suggested one thing.
107
00:06:59,520 --> 00:07:03,240
There are such things
as battle songs.
108
00:07:03,240 --> 00:07:05,080
INDRI HOOTS
109
00:07:06,120 --> 00:07:10,440
Songs that say,
"Get out, this is my territory!"
110
00:07:10,440 --> 00:07:12,480
INDRIS CALL
111
00:07:13,480 --> 00:07:16,920
GENTLE BIRDSONG
112
00:07:16,920 --> 00:07:19,080
It seemed to be a clear example
113
00:07:19,080 --> 00:07:22,400
of Darwin's theory
of sexual selection.
114
00:07:24,200 --> 00:07:27,640
A male singing to defend
his breeding patch.
115
00:07:29,040 --> 00:07:31,720
But this was still just guesswork.
116
00:07:33,720 --> 00:07:37,960
We suspected that songs
could be weapons of war,
117
00:07:37,960 --> 00:07:40,880
but it was the next recording
that proved it.
118
00:07:44,960 --> 00:07:49,000
LILTING CHIRPS
119
00:07:53,040 --> 00:07:55,000
LILTING CHIRPS
120
00:07:55,000 --> 00:07:58,640
This is the song
of a male great tit.
121
00:07:58,640 --> 00:08:01,160
A call, a very simple song.
122
00:08:03,720 --> 00:08:05,760
It was recorded by a scientist
123
00:08:05,760 --> 00:08:09,280
who's been a pioneer
in understanding animal song.
124
00:08:10,840 --> 00:08:12,560
Professor John Krebs.
125
00:08:14,120 --> 00:08:16,960
He was the one who proved
for the first time
126
00:08:16,960 --> 00:08:20,440
exactly why my playback trick
in Madagascar had worked.
127
00:08:27,960 --> 00:08:30,600
Spring 1975.
128
00:08:33,080 --> 00:08:37,280
Back then, John was a young lecturer
at the University of Oxford,
129
00:08:37,280 --> 00:08:40,920
researching the birds in woodland
just outside the city.
130
00:08:42,760 --> 00:08:47,160
First, he plotted the territories
of all the pairs of great tits.
131
00:08:48,520 --> 00:08:52,280
Next, he recorded the songs
of the males.
132
00:08:52,280 --> 00:08:55,840
REPEATING HIGH-LOW CHIRPS
133
00:08:59,040 --> 00:09:01,720
Female great tits do not sing.
134
00:09:04,280 --> 00:09:06,800
Then, on a particular morning
in February,
135
00:09:06,800 --> 00:09:10,960
I came out with mist nets
to catch the birds,
136
00:09:10,960 --> 00:09:14,080
and I caught all the pairs of birds
that were in the woods.
137
00:09:15,440 --> 00:09:18,760
Now there were no great tits,
138
00:09:18,760 --> 00:09:21,600
just empty great tit territories.
139
00:09:21,600 --> 00:09:24,560
BIRDSONG
140
00:09:24,560 --> 00:09:29,000
In some, John replaced
the great tits with loudspeakers
141
00:09:29,000 --> 00:09:34,040
that played the sounds of the birds
that he had temporarily removed.
142
00:09:34,040 --> 00:09:36,440
RECORDING OF GREAT TIT SONG PLAYS
143
00:09:36,440 --> 00:09:38,880
If the song was a "keep out" signal,
144
00:09:38,880 --> 00:09:41,960
then new great tits
would avoid these patches.
145
00:09:41,960 --> 00:09:46,400
RECORDING CONTINUES
146
00:09:46,400 --> 00:09:49,000
Other territories were left silent.
147
00:09:49,000 --> 00:09:52,320
No speakers, no great tit song.
148
00:09:53,440 --> 00:09:58,040
New great tits should realise these
spaces were empty and available,
149
00:09:58,040 --> 00:09:59,920
and settle there quickly.
150
00:09:59,920 --> 00:10:02,480
RECORDING CONTINUES
151
00:10:02,480 --> 00:10:06,320
But how would John know
that it was due to a great tit song
152
00:10:06,320 --> 00:10:08,640
that newcomers had been deterred?
153
00:10:10,480 --> 00:10:12,960
Perhaps any sound would
have had the same effect.
154
00:10:14,640 --> 00:10:19,720
So, in some territories, he played
a recording of a tin whistle.
155
00:10:19,720 --> 00:10:22,960
RECORDING OF TUNELESS TIN WHISTLE
PLAYS
156
00:10:22,960 --> 00:10:24,520
He could have chosen anything,
157
00:10:24,520 --> 00:10:28,080
as long as it sounded
nothing like a great tit.
158
00:10:28,080 --> 00:10:30,200
And then I watched to see
what happened,
159
00:10:30,200 --> 00:10:32,320
and new birds came into the wood,
160
00:10:32,320 --> 00:10:34,560
because this is
a prime breeding area,
161
00:10:34,560 --> 00:10:36,600
so birds love to come here to breed.
162
00:10:38,000 --> 00:10:40,040
IT CHIRPS
163
00:10:40,040 --> 00:10:43,440
John discovered that the first
territories that were taken
164
00:10:43,440 --> 00:10:45,600
were the silent territories,
165
00:10:45,600 --> 00:10:47,840
and the ones with the tin whistle.
166
00:10:47,840 --> 00:10:49,600
TIN WHISTLE RECORDING CONTINUES
167
00:10:49,600 --> 00:10:53,240
Crucially, the territories in which
the great tit song was played
168
00:10:53,240 --> 00:10:57,120
remained empty of new great tits.
169
00:10:57,120 --> 00:11:00,120
By looking at the detail
of that pattern of settling,
170
00:11:00,120 --> 00:11:03,320
I was able to show experimentally
171
00:11:03,320 --> 00:11:06,400
that song is an effective
"keep out" signal.
172
00:11:07,960 --> 00:11:11,440
THEY SING
173
00:11:11,440 --> 00:11:14,640
Professor Krebs' predictions
were exactly right.
174
00:11:14,640 --> 00:11:19,600
Song was a "keep out" signal
to other great tits.
175
00:11:22,520 --> 00:11:26,080
For the very first time,
there was scientific evidence
176
00:11:26,080 --> 00:11:31,320
that song was being used
to intimidate rivals,
177
00:11:31,320 --> 00:11:35,680
just as I had seen with the indris
in Madagascar in the '60s.
178
00:11:37,840 --> 00:11:40,960
How astonishing
that it was only in 1975
179
00:11:40,960 --> 00:11:44,040
that this was proved
for the first time.
180
00:11:45,360 --> 00:11:48,440
The song of the great tit
had made history.
181
00:11:51,680 --> 00:11:54,000
LILTING CHIRPS
182
00:11:54,000 --> 00:11:57,040
BIRDSONG
183
00:12:03,600 --> 00:12:05,840
Open a window in spring,
184
00:12:05,840 --> 00:12:08,760
and these are the singers
that serenade us.
185
00:12:08,760 --> 00:12:11,240
CUCKOO! CUCKOO!
186
00:12:11,240 --> 00:12:12,600
Songbirds.
187
00:12:14,720 --> 00:12:16,320
They make up about half
188
00:12:16,320 --> 00:12:19,080
of the 10,000
species of birds in the world.
189
00:12:21,120 --> 00:12:24,680
Five of my sevens songs
are sung by them.
190
00:12:27,960 --> 00:12:32,960
Birds have the most advanced vocal
organs in the entire natural world.
191
00:12:32,960 --> 00:12:34,480
DEEPENING CHIRPS
192
00:12:34,480 --> 00:12:38,480
We have our voice box
at the top of our windpipe,
193
00:12:38,480 --> 00:12:41,920
but their equivalent
is at the base of theirs -
194
00:12:41,920 --> 00:12:44,640
it's an organ called a syrinx.
195
00:12:44,640 --> 00:12:48,200
They're the only creatures
on Earth to have one of these,
196
00:12:48,200 --> 00:12:50,160
and the syrinx of the songbird
197
00:12:50,160 --> 00:12:52,560
is the most complex of them all.
198
00:12:52,560 --> 00:12:53,640
BIRD SINGS
199
00:12:53,640 --> 00:12:55,360
As breath passes through it,
200
00:12:55,360 --> 00:12:57,480
muscles contract and vibrate,
201
00:12:57,480 --> 00:13:00,080
creating the sounds we call song.
202
00:13:00,080 --> 00:13:01,680
It can produce different notes
203
00:13:01,680 --> 00:13:04,440
from the left and right sides
simultaneously.
204
00:13:04,440 --> 00:13:06,200
COMPLEX BIRDSONG
205
00:13:06,200 --> 00:13:11,040
It's like having two voice boxes
that can operate at the same time.
206
00:13:11,040 --> 00:13:12,760
CHATTERING SONG
207
00:13:12,760 --> 00:13:15,360
So this is how songbirds can perform
208
00:13:15,360 --> 00:13:19,520
such unparalleled feats
of vocal gymnastics.
209
00:13:19,520 --> 00:13:23,280
But working out WHY they do
is far more complex.
210
00:13:23,280 --> 00:13:27,360
REPEATING RASPING CHIRPS
211
00:13:27,360 --> 00:13:29,320
REPEATING BUZZING CALL
212
00:13:29,320 --> 00:13:35,080
Each note lasts just a tiny moment
and then disappears.
213
00:13:35,080 --> 00:13:38,560
HIGH, BUBBLING CALL
214
00:13:38,560 --> 00:13:43,160
That presents anyone who wants
to study it with a problem.
215
00:13:43,160 --> 00:13:45,280
HIGH, RAPID SONG
216
00:13:45,280 --> 00:13:48,240
But there are two
relatively recent inventions
217
00:13:48,240 --> 00:13:50,880
that have helped us
to capture songs.
218
00:13:50,880 --> 00:13:52,720
CHATTERING CALL
219
00:13:52,720 --> 00:13:57,600
It was with a gun mic like this,
inside its windshield,
220
00:13:57,600 --> 00:14:03,800
that John Krebs caught the fleeting
sound of the great tit.
221
00:14:03,800 --> 00:14:07,800
But it was the ability
to take that recorded sound
222
00:14:07,800 --> 00:14:11,360
and then turn it
into a visual picture
223
00:14:11,360 --> 00:14:14,480
that enabled us
to analyse that sound
224
00:14:14,480 --> 00:14:16,880
and reveal its full complexity.
225
00:14:18,520 --> 00:14:19,680
LILTING GREAT TIT SONG
226
00:14:19,680 --> 00:14:23,040
This is an animation
of the male great tit song,
227
00:14:23,040 --> 00:14:26,320
generated by a machine
called a spectrograph.
228
00:14:28,520 --> 00:14:32,160
It changes the song into an image
that's possible to read.
229
00:14:32,160 --> 00:14:33,640
DEEP CHIRPS
230
00:14:33,640 --> 00:14:37,920
Slowed down, we can see that the
great tit song is relatively simple.
231
00:14:37,920 --> 00:14:39,600
CHIRPS CONTINUE
232
00:14:39,600 --> 00:14:44,280
It's composed of two notes -
one high and one low - repeated.
233
00:14:45,480 --> 00:14:47,520
REPEATED HIGH CHIRPS
234
00:14:47,520 --> 00:14:49,160
What we hear is very similar
235
00:14:49,160 --> 00:14:51,240
to what we can see
on the spectrograph.
236
00:14:51,240 --> 00:14:52,840
CHIRPS CONTINUES
237
00:14:52,840 --> 00:14:55,400
But compare that to the song
of the male wren.
238
00:14:55,400 --> 00:14:58,880
HIGH, RAPID, COMPLEX SONG
239
00:15:00,000 --> 00:15:04,080
What we hear is not what
the bird hears.
240
00:15:04,080 --> 00:15:08,080
Birds live on a different timescale,
241
00:15:08,080 --> 00:15:11,240
at a different pace from us.
242
00:15:11,240 --> 00:15:15,240
And they can hear details
in their song
243
00:15:15,240 --> 00:15:19,440
that are impossible
for us to hear.
244
00:15:21,200 --> 00:15:25,400
It's only when we use a spectrogram
that these details are revealed
245
00:15:27,760 --> 00:15:29,000
A trill...
246
00:15:30,280 --> 00:15:32,880
..a connecting note...
247
00:15:32,880 --> 00:15:34,960
..another trill...
248
00:15:34,960 --> 00:15:37,720
..and then a rapid
burst of trills at the end.
249
00:15:37,720 --> 00:15:39,360
RAPID TRILLS
250
00:15:39,360 --> 00:15:42,320
Now we can see that there
are perhaps 100 notes
251
00:15:42,320 --> 00:15:46,240
or more in a song that may
last only a few seconds.
252
00:15:46,240 --> 00:15:48,800
RAPID TRILLS
253
00:15:48,800 --> 00:15:52,360
SLOWED, UNDULATING BIRDSONG
254
00:15:53,280 --> 00:15:54,840
RAPID TRILLS
255
00:16:01,960 --> 00:16:08,000
What the spectrograms show are
these songs are far more complicated
256
00:16:08,000 --> 00:16:12,360
and complex than we could
possibly have imagined.
257
00:16:12,360 --> 00:16:15,800
But why complicate things so?
258
00:16:15,800 --> 00:16:18,840
The calls of the indri
and the great tit
259
00:16:18,840 --> 00:16:20,680
worked perfectly well.
260
00:16:21,920 --> 00:16:24,480
The answer, of course, is sex.
261
00:16:32,920 --> 00:16:38,240
That is the reason why so many birds
have such complex mating songs.
262
00:16:38,240 --> 00:16:42,720
CHIRPS AND CHIRRUPS
263
00:16:42,720 --> 00:16:45,840
Females seem to prefer them.
264
00:16:45,840 --> 00:16:48,560
The more intricate and detailed
the song is,
265
00:16:48,560 --> 00:16:50,920
the better the male's chances.
266
00:16:55,360 --> 00:16:58,560
And my third song helps
to explain why.
267
00:17:01,560 --> 00:17:04,080
RHYTHMIC BIRDSONG
268
00:17:07,320 --> 00:17:12,120
It's a recording of a nightingale
that is my next chosen song.
269
00:17:12,120 --> 00:17:15,400
NIGHTINGALE SINGS
270
00:17:15,400 --> 00:17:18,840
This is a male singing for a mate.
271
00:17:20,360 --> 00:17:25,160
Just as with the great tit,
the females do not sing.
272
00:17:25,160 --> 00:17:28,920
But they are the ones the males
are singing for.
273
00:17:28,920 --> 00:17:31,920
So why do they prefer more
complex songs?
274
00:17:38,680 --> 00:17:42,760
It's a question that has puzzled
scientists for centuries.
275
00:17:45,120 --> 00:17:48,320
Charles Darwin's answer
was that the females
276
00:17:48,320 --> 00:17:50,920
have an aesthetic sense.
277
00:17:50,920 --> 00:17:54,040
After all, human beings
appreciate beauty.
278
00:17:54,040 --> 00:17:56,800
Why shouldn't other animals
do so too?
279
00:17:59,000 --> 00:18:02,560
But the question Darwin
didn't answer was
280
00:18:02,560 --> 00:18:06,080
WHY should the females
have an aesthetic sense?
281
00:18:08,320 --> 00:18:12,640
Here on the streets of Berlin,
we might just find the answer.
282
00:18:15,800 --> 00:18:21,440
Spring attracts over 2,000
nightingales to this city each year.
283
00:18:21,440 --> 00:18:25,400
They flock to Berlin because
it's filled with green space,
284
00:18:25,400 --> 00:18:28,640
much of which has been left untamed.
285
00:18:28,640 --> 00:18:32,080
And it's these wild places
that they love.
286
00:18:35,960 --> 00:18:40,840
In one of its most popular parks,
a male nightingale.
287
00:18:43,880 --> 00:18:48,080
He, like the other males, arrived
from Africa a few weeks ago
288
00:18:48,080 --> 00:18:52,080
and has spent his time singing
to defend a breeding patch.
289
00:18:54,080 --> 00:18:59,360
But tonight, when the lights go out,
he will change his tune
290
00:18:59,360 --> 00:19:02,200
because the females have arrived.
291
00:19:02,200 --> 00:19:05,880
RAPID CHIRPS
292
00:19:07,240 --> 00:19:11,960
Nightingales migrate at night,
and when the females fly in,
293
00:19:11,960 --> 00:19:16,240
under cover of dark, they are met
with songs of seduction.
294
00:19:16,240 --> 00:19:21,320
COMPLEX TWEETS, TRILLS AND CHIRPS
295
00:19:26,560 --> 00:19:32,000
Dr Conny Landgraf made our
recording of the nightingale's song.
296
00:19:37,280 --> 00:19:41,080
So right now, there's one...
Oh, no there is a second male.
297
00:19:41,080 --> 00:19:44,800
So it's already two males
in a vocal contest.
298
00:19:46,800 --> 00:19:51,640
What the females do is that they do
not take the first male that comes
299
00:19:51,640 --> 00:19:56,920
their way, but they prospect and
inspect different male territories.
300
00:19:56,920 --> 00:19:59,440
And this is like a
speed dating that is actually
301
00:19:59,440 --> 00:20:01,480
going on in the middle of the night.
302
00:20:01,480 --> 00:20:04,080
OVERLAPPING BIRDSONGS
303
00:20:04,080 --> 00:20:08,760
Each male sings his heart out
and the females listen.
304
00:20:09,760 --> 00:20:10,840
DING
305
00:20:10,840 --> 00:20:12,040
Time's up!
306
00:20:12,040 --> 00:20:14,880
What does the next potential
mate sound like?
307
00:20:14,880 --> 00:20:17,280
DING
308
00:20:14,880 --> 00:20:17,280
Time's up again.
309
00:20:17,280 --> 00:20:19,680
Does the next
one have a better song?
310
00:20:19,680 --> 00:20:21,160
QUICKFIRE CHIRPS
311
00:20:21,160 --> 00:20:22,400
DING
312
00:20:25,680 --> 00:20:32,880
Nightingales have extremely large
song repertoires, up to 250 songs.
313
00:20:32,880 --> 00:20:38,120
And also they are able
to produce really challenging
314
00:20:38,120 --> 00:20:43,480
syllables and phrases, thinking
of trill or bass elements.
315
00:20:43,480 --> 00:20:47,200
So these are very fast,
repeated single notes.
316
00:20:47,200 --> 00:20:48,960
So this is remarkable.
317
00:20:50,280 --> 00:20:53,320
The more complex his song,
318
00:20:53,320 --> 00:20:56,240
the more beautiful it seems
to the female.
319
00:20:57,280 --> 00:21:00,640
But why? Does the female have
an aesthetic sense,
320
00:21:00,640 --> 00:21:03,400
as Darwin suggested?
321
00:21:03,400 --> 00:21:07,800
Conny and her team set up
an experiment to find out.
322
00:21:07,800 --> 00:21:12,640
First, they recorded males singing
at the beginning of spring.
323
00:21:13,640 --> 00:21:17,440
Then they set up cameras to record
nightingale nests
324
00:21:17,440 --> 00:21:19,160
later in the season.
325
00:21:21,400 --> 00:21:25,680
Male nightingales play a crucial
role in feeding chicks.
326
00:21:31,640 --> 00:21:35,120
What we found in the end
was that there was indeed
327
00:21:35,120 --> 00:21:38,160
a very strong correlation
between his song
328
00:21:38,160 --> 00:21:40,600
and feeding rates at the nest.
329
00:21:40,600 --> 00:21:44,600
So it's like a promise
that the males give to the females
330
00:21:44,600 --> 00:21:46,000
to be good fathers.
331
00:21:48,800 --> 00:21:51,600
So, for example,
a male could be saying,
332
00:21:51,600 --> 00:21:54,640
"Hey, there,
I'm a healthy, strong man,
333
00:21:54,640 --> 00:21:59,000
"I know this area and all the
best feeding places very well,
334
00:21:59,000 --> 00:22:01,920
"so come settle down
and mate with me."
335
00:22:06,200 --> 00:22:10,280
Females, Darwin said, chose
the males with the most beautiful
336
00:22:10,280 --> 00:22:15,240
songs, and my third recording
has demonstrated why.
337
00:22:15,240 --> 00:22:17,520
Better singers are better fathers.
338
00:22:19,240 --> 00:22:22,840
Songs can be a promise
of devoted parenthood.
339
00:22:36,320 --> 00:22:39,640
There are some songs
that it's impossible for me
340
00:22:39,640 --> 00:22:42,720
to imagine life without.
341
00:22:42,720 --> 00:22:44,680
ROBIN SINGS
342
00:22:44,680 --> 00:22:47,560
Songs that accompany
our daily lives.
343
00:22:49,480 --> 00:22:52,600
It's one of the most characteristic
sounds, and to my ear
344
00:22:52,600 --> 00:22:55,840
is one of the most delightful
of the English winter -
345
00:22:55,840 --> 00:22:57,920
the song of the robin.
346
00:23:02,120 --> 00:23:04,320
These are the songs
that Charles Darwin
347
00:23:04,320 --> 00:23:05,920
would have listened to as a boy.
348
00:23:07,000 --> 00:23:11,840
And much of our research into song
has centred on British species.
349
00:23:13,800 --> 00:23:17,560
Indeed, for much of the last
century, we thought birdsong
350
00:23:17,560 --> 00:23:20,280
originated here
in northern latitudes.
351
00:23:23,040 --> 00:23:27,720
But what if Darwin had been raised
on the other side of the world?
352
00:23:27,720 --> 00:23:30,520
Would his theories about song
have been different?
353
00:23:32,560 --> 00:23:35,880
CACOPHONY OF ANIMAL CALLS
354
00:23:35,880 --> 00:23:38,280
The forests of Australia.
355
00:23:45,120 --> 00:23:48,640
Out here, scientists are
in the process of changing
356
00:23:48,640 --> 00:23:51,320
many of our old ideas about song.
357
00:23:52,840 --> 00:23:55,320
HOOTING CRY
358
00:23:56,480 --> 00:24:00,840
They found fossil and
DNA evidence of early songbirds,
359
00:24:00,840 --> 00:24:04,160
which show that this, in fact,
is where song began.
360
00:24:09,080 --> 00:24:12,240
It was here in Australia
that the ancestors
361
00:24:12,240 --> 00:24:15,160
of all songbirds first evolved.
362
00:24:23,640 --> 00:24:27,840
Song number four is from one
of the original songbirds'
363
00:24:27,840 --> 00:24:29,880
most remarkable descendants.
364
00:24:31,480 --> 00:24:35,240
And it's one that amazes me
every time I hear it.
365
00:24:35,240 --> 00:24:40,160
QUIZZICAL WHISTLES
366
00:24:41,760 --> 00:24:46,000
It was recorded in the forests
just outside Melbourne,
367
00:24:46,000 --> 00:24:49,320
and it was the first time
that wild birdsong had ever
368
00:24:49,320 --> 00:24:51,360
been broadcast in Australia.
369
00:24:52,680 --> 00:24:54,200
BIRD CALLS
370
00:24:58,000 --> 00:25:02,520
The song of the lyrebird, in my
view, is one of the most complex
371
00:25:02,520 --> 00:25:06,920
and beautiful in the whole
of the natural world.
372
00:25:06,920 --> 00:25:09,560
And what gives it its complexity
373
00:25:09,560 --> 00:25:12,520
is the talent that a lyrebird has
374
00:25:12,520 --> 00:25:13,760
for mimicry.
375
00:25:15,920 --> 00:25:17,440
ON RECORD: Crimson parrot.
376
00:25:17,440 --> 00:25:19,480
BIRD CALLS
377
00:25:21,880 --> 00:25:23,880
The kookaburra.
378
00:25:23,880 --> 00:25:25,400
BIRD CALLS
379
00:25:27,480 --> 00:25:30,720
The descendants
of that lyrebird, I'm happy to say,
380
00:25:30,720 --> 00:25:33,520
are still singing in those forests,
381
00:25:33,520 --> 00:25:36,320
and I've been lucky enough to listen
382
00:25:36,320 --> 00:25:37,920
to one of them myself.
383
00:25:39,360 --> 00:25:45,400
It was the 1990s when the BBC series
Life Of Birds took me to Australia.
384
00:25:48,440 --> 00:25:53,040
I wanted to film a lyrebird
who was the most astounding mimic.
385
00:25:56,720 --> 00:26:00,640
To persuade females to come close
and admire his plumes, he sings
386
00:26:00,640 --> 00:26:03,000
the most complex song he can manage,
387
00:26:03,000 --> 00:26:06,520
and he does that by copying
the songs of all the other birds
388
00:26:06,520 --> 00:26:07,840
he hears around him,
389
00:26:07,840 --> 00:26:09,520
such as the kookaburra.
390
00:26:11,400 --> 00:26:13,120
KOOKABURRA CALL
391
00:26:14,280 --> 00:26:18,440
He can imitate the calls
of at least 20 different species.
392
00:26:21,840 --> 00:26:25,960
He also, in his attempt to out-sing
his rivals, incorporates other
393
00:26:25,960 --> 00:26:28,840
sounds that he hears in the forest.
394
00:26:28,840 --> 00:26:30,240
CLICKING
395
00:26:30,240 --> 00:26:32,040
That was a camera shutter.
396
00:26:38,080 --> 00:26:39,600
And again.
397
00:26:43,080 --> 00:26:45,400
And now a camera
with a motor drive.
398
00:26:46,920 --> 00:26:48,760
CLICK AND WHIR
399
00:26:48,760 --> 00:26:50,840
ALARM BLARES
400
00:26:52,760 --> 00:26:54,480
And that's a car alarm.
401
00:27:03,360 --> 00:27:08,160
And now the sounds of foresters
and their chainsaws working nearby.
402
00:27:08,160 --> 00:27:10,240
BUZZING
403
00:27:13,440 --> 00:27:15,120
SAWING
404
00:27:16,520 --> 00:27:20,240
Since this remarkable clip
was broadcast, millions of people
405
00:27:20,240 --> 00:27:21,960
have watched it online.
406
00:27:23,960 --> 00:27:27,880
Scientists have discovered
a lot more about lyrebird song
407
00:27:27,880 --> 00:27:30,040
since that recording was made.
408
00:27:30,040 --> 00:27:34,600
That particular bird was accustomed
to the presence of human beings
409
00:27:34,600 --> 00:27:39,160
nearby, but much wilder
birds produce something
410
00:27:39,160 --> 00:27:40,840
even more fascinating.
411
00:27:43,040 --> 00:27:46,200
Sunrise, Sherbrooke Forest, today.
412
00:27:48,640 --> 00:27:50,680
One voice in the dawn chorus
413
00:27:50,680 --> 00:27:54,640
is louder than any other -
the male lyrebird.
414
00:27:58,240 --> 00:28:00,200
BIRD CALLS
415
00:28:02,840 --> 00:28:07,440
It's the breeding season and they're
busy trying to attract mates.
416
00:28:13,960 --> 00:28:17,240
Clearing undergrowth
from the forest floor creates
417
00:28:17,240 --> 00:28:19,600
an arena for his mating display.
418
00:28:27,560 --> 00:28:30,600
Once the stage is set,
the show can begin.
419
00:28:32,720 --> 00:28:35,840
CALLING
420
00:28:35,840 --> 00:28:38,600
It's unlike any other in
the natural world.
421
00:28:42,040 --> 00:28:43,720
Since I heard this song,
422
00:28:43,720 --> 00:28:47,560
scientists have analysed it
and broken it down into parts.
423
00:28:51,720 --> 00:28:54,400
Song A comes first.
424
00:28:54,400 --> 00:28:56,480
CLICKS AND WHISTLES
425
00:28:59,960 --> 00:29:05,960
Now song B, a loud low shriek,
which alternates with song C,
426
00:29:05,960 --> 00:29:08,400
a quiet, very soft clicking sound.
427
00:29:16,400 --> 00:29:18,600
A female arrives.
428
00:29:20,480 --> 00:29:21,960
But no, she loses interest.
429
00:29:25,720 --> 00:29:29,600
What he does next will need
to be even more impressive.
430
00:29:40,160 --> 00:29:44,040
Few have analysed the grand finale
of the male lyrebird song
431
00:29:44,040 --> 00:29:48,680
more intensively than
Dr Anastasia Dalziell.
432
00:29:48,680 --> 00:29:53,000
She and her team were the first ones
to film it properly.
433
00:29:54,400 --> 00:29:57,800
We thought no-one's going to believe
us until we've actually filmed it.
434
00:29:57,800 --> 00:30:02,200
It's really not like anything else
that has been described previously
435
00:30:02,200 --> 00:30:04,400
in birds or any other animals.
436
00:30:08,360 --> 00:30:11,600
It was by studying the recordings
from their remote camera
437
00:30:11,600 --> 00:30:14,640
that the team were able
to understand the real secret
438
00:30:14,640 --> 00:30:16,800
of the male lyrebird song.
439
00:30:18,280 --> 00:30:22,360
And it's this footage together
with our own that enables us to show
440
00:30:22,360 --> 00:30:26,280
this remarkable behaviour
on television for the first time.
441
00:30:28,280 --> 00:30:32,640
Having sung A, B and C
and been rejected, the male now
442
00:30:32,640 --> 00:30:33,840
begins Song D.
443
00:30:35,040 --> 00:30:36,880
So this final song,
444
00:30:36,880 --> 00:30:41,800
it's the sound of a flock
of small birds mobbing,
445
00:30:41,800 --> 00:30:46,200
reacting to a stationary or
a hidden predator like a snake.
446
00:30:46,200 --> 00:30:48,760
And this was totally bizarre.
447
00:30:48,760 --> 00:30:51,920
So why is he imitating
a flock of birds?
448
00:30:53,600 --> 00:30:55,800
Well, a predator means danger.
449
00:30:55,800 --> 00:30:59,640
So at the sound of an alarm call,
the female freezes.
450
00:31:04,400 --> 00:31:07,120
The forest is no longer
a safe place.
451
00:31:10,800 --> 00:31:14,640
Now the male takes advantage
of her panic.
452
00:31:14,640 --> 00:31:16,880
He jumps on top of her to mate.
453
00:31:19,560 --> 00:31:22,320
It's hard for us to see
her under his feathers,
454
00:31:22,320 --> 00:31:25,480
and it's hard for her
to see out from under them.
455
00:31:26,880 --> 00:31:31,360
He's doing everything he can
to disorientate and confuse her.
456
00:31:36,160 --> 00:31:38,920
The male is actually
telling her a big fib -
457
00:31:38,920 --> 00:31:41,720
don't leave me because out there,
there's a hidden predator
458
00:31:41,720 --> 00:31:43,280
that you haven't seen.
459
00:31:43,280 --> 00:31:45,880
To put it another way,
it's like saying,
460
00:31:45,880 --> 00:31:47,840
"Baby, it's dangerous outside.
461
00:31:47,840 --> 00:31:51,320
"Come back here with me
where it's nice and safe."
462
00:31:54,880 --> 00:31:59,120
The lyrebird is, in fact,
a bird that tells lies.
463
00:32:00,880 --> 00:32:03,360
His song is an acoustic illusion.
464
00:32:05,480 --> 00:32:07,400
Up to now, scientists have thought
465
00:32:07,400 --> 00:32:10,280
that song was an honest
signal from the male.
466
00:32:11,280 --> 00:32:16,800
But it seems song can also
be manipulative and false.
467
00:32:26,880 --> 00:32:30,800
Not far away, in the Blue Mountains
near Sydney,
468
00:32:30,800 --> 00:32:34,960
scientist Victoria Austin
is studying the female lyrebird.
469
00:32:38,880 --> 00:32:40,520
What she's listening for
470
00:32:40,520 --> 00:32:43,240
is something very few
people have heard.
471
00:32:44,360 --> 00:32:47,320
So what I'm doing now is
just preparing my recorder
472
00:32:47,320 --> 00:32:51,520
because we're about to head to a
nest and we're hoping to be able
473
00:32:51,520 --> 00:32:54,480
to record the female lyrebird
that resides in that area.
474
00:32:57,080 --> 00:33:01,080
The female lyrebird
is the opposite of her flashy mate.
475
00:33:01,080 --> 00:33:02,520
She's secretive.
476
00:33:04,920 --> 00:33:08,880
When she is seen, she's often
mistaken for a juvenile male.
477
00:33:11,120 --> 00:33:14,640
To most people, she's invisible,
478
00:33:14,640 --> 00:33:17,000
but Victoria knows how to find her.
479
00:33:19,600 --> 00:33:23,720
This old nest suggests
that she may be nearby.
480
00:33:24,760 --> 00:33:26,280
And there she is.
481
00:33:27,680 --> 00:33:31,760
This rarely heard sound
is her whistle song.
482
00:33:31,760 --> 00:33:33,680
CALLING
483
00:33:37,400 --> 00:33:39,920
In Darwin's theory of
sexual selection,
484
00:33:39,920 --> 00:33:45,000
males sing to attract females,
and females drive the evolution
485
00:33:45,000 --> 00:33:48,240
of song by preferring
ever more complex songs.
486
00:33:50,120 --> 00:33:53,560
The females themselves do not sing.
487
00:33:53,560 --> 00:33:57,640
Yet here we are listening
to a female lyrebird singing.
488
00:34:00,200 --> 00:34:02,920
So what is the function of her song?
489
00:34:06,280 --> 00:34:09,320
Well, the female raises
her chicks alone.
490
00:34:12,320 --> 00:34:17,080
The male plays no part,
so it's extremely important
491
00:34:17,080 --> 00:34:20,560
for her to maintain her territory
and the food within it.
492
00:34:21,960 --> 00:34:26,440
She uses song to let everyone know
that it's her patch.
493
00:34:26,440 --> 00:34:28,240
CALLING
494
00:34:31,440 --> 00:34:33,960
And Victoria is also researching
495
00:34:33,960 --> 00:34:36,560
whether song helps her
in other ways.
496
00:34:37,960 --> 00:34:41,120
In the last few years,
she's been recording their songs
497
00:34:41,120 --> 00:34:43,040
across the Blue Mountains.
498
00:34:47,600 --> 00:34:52,160
This is one of them -
a female mimicking a goshawk.
499
00:34:52,160 --> 00:34:54,040
BIRDSONG
500
00:34:58,880 --> 00:35:00,240
It's very accurate.
501
00:35:00,240 --> 00:35:03,280
If you were to play this call
alongside an actual goshawk,
502
00:35:03,280 --> 00:35:05,760
it'd be very difficult to tell
the difference, if you were able
503
00:35:05,760 --> 00:35:08,280
to tell the difference at all.
504
00:35:08,280 --> 00:35:11,960
So what is the purpose of
this perfect impersonation?
505
00:35:14,120 --> 00:35:18,440
She's using it to deceive predators
into thinking she's more dangerous
506
00:35:18,440 --> 00:35:20,080
than she actually is.
507
00:35:25,440 --> 00:35:28,920
She is just as talented
as the more famous male.
508
00:35:32,080 --> 00:35:35,280
So the biggest purpose of
what we're doing working
509
00:35:35,280 --> 00:35:40,640
with these female lyrebirds is to
dispel this long-held myth that only
510
00:35:40,640 --> 00:35:42,560
recently was shown not to be true,
511
00:35:42,560 --> 00:35:45,680
and that is the idea that female
birds don't sing,
512
00:35:45,680 --> 00:35:47,200
or that it's very rare.
513
00:35:47,200 --> 00:35:49,440
And that's just simply not the case.
514
00:35:52,560 --> 00:35:57,160
This surely challenges
Darwin's theory,
515
00:35:57,160 --> 00:36:00,320
as does my next revolutionary song.
516
00:36:08,640 --> 00:36:11,960
My fifth song was also
recorded in Australia.
517
00:36:13,880 --> 00:36:18,800
It, too, like the song of the female
lyrebird, has rarely been heard.
518
00:36:21,440 --> 00:36:26,080
It's important because its
existence changes our idea
519
00:36:26,080 --> 00:36:27,920
of what song actually is.
520
00:36:29,680 --> 00:36:31,560
BIRDSONG
521
00:36:33,640 --> 00:36:38,040
This is a fairly common Australian
bird called a fairy wren.
522
00:36:42,440 --> 00:36:46,680
We filmed these birds for a BBC
series back in the 1990s.
523
00:36:51,040 --> 00:36:55,920
We went there to film it
because it's extremely promiscuous.
524
00:36:55,920 --> 00:37:00,360
Both male and female will mate
with many different partners.
525
00:37:01,440 --> 00:37:05,960
But what few people realised
at the time, and I certainly didn't,
526
00:37:05,960 --> 00:37:09,680
was that it's not just
the male that sings.
527
00:37:12,240 --> 00:37:13,920
The female does, too.
528
00:37:20,240 --> 00:37:23,680
This is Canberra Botanical Gardens.
529
00:37:25,400 --> 00:37:28,520
Professor Naomi Langmore
was the scientist
530
00:37:28,520 --> 00:37:31,000
who made our fairy wren recording.
531
00:37:32,040 --> 00:37:36,720
She was one of the first to realise
the significance of female song.
532
00:37:40,560 --> 00:37:44,680
The male fairy wren, with glorious,
iridescent blue and striking
533
00:37:44,680 --> 00:37:47,480
black plumage is rather
difficult to miss.
534
00:37:50,960 --> 00:37:52,640
So where is the female?
535
00:37:53,680 --> 00:37:57,120
Well, not at the top of a perch
like the male,
536
00:37:57,120 --> 00:37:59,920
but instead here,
hiding in the bushes.
537
00:38:02,240 --> 00:38:06,560
She is comparatively rather dull -
a drab brown.
538
00:38:07,760 --> 00:38:11,960
Because females are often less
flashy and eye-catching than males,
539
00:38:11,960 --> 00:38:14,760
it's very easy to miss female song.
540
00:38:14,760 --> 00:38:17,360
BIRDSONG
541
00:38:17,360 --> 00:38:19,200
But sing she does.
542
00:38:22,440 --> 00:38:25,880
Just as male song is used in
competition with other males,
543
00:38:25,880 --> 00:38:30,040
female song seems to be in
competition with other females.
544
00:38:31,440 --> 00:38:34,640
But why didn't
we hear her before now?
545
00:38:34,640 --> 00:38:39,080
Is it really just because she's less
noticeable than the male?
546
00:38:39,080 --> 00:38:41,080
In the history of the study
of birdsong,
547
00:38:41,080 --> 00:38:44,400
most research was done in the
northern hemisphere, in Europe
548
00:38:44,400 --> 00:38:46,920
and North America,
and in those regions,
549
00:38:46,920 --> 00:38:49,160
female song is comparatively rare.
550
00:38:49,160 --> 00:38:52,560
And so researchers working
in those regions generalised
551
00:38:52,560 --> 00:38:55,800
from what they were observing
in their local birds and assumed
552
00:38:55,800 --> 00:38:59,440
that male song was the norm
throughout the world.
553
00:38:59,440 --> 00:39:02,200
A male-biased view of birdsong had,
554
00:39:02,200 --> 00:39:05,240
to an extent, deafened
us to female song.
555
00:39:06,600 --> 00:39:09,840
So when I was doing my research,
it was basically assumed
556
00:39:09,840 --> 00:39:13,520
that it's the male that sings
and the female doesn't.
557
00:39:13,520 --> 00:39:16,040
Maybe that's because most
of the scientists were males
558
00:39:16,040 --> 00:39:17,480
who were studying birdsong.
559
00:39:17,480 --> 00:39:20,840
But now there's a new generation
of female scientists coming through
560
00:39:20,840 --> 00:39:24,440
studying birdsong
all around the world
561
00:39:24,440 --> 00:39:27,920
and discovering that actually female
song is very common
562
00:39:27,920 --> 00:39:30,120
and occurs in more species than not.
563
00:39:31,280 --> 00:39:34,320
And it's only now that
they're properly being heard.
564
00:39:35,920 --> 00:39:39,920
Naomi and her colleagues
have discovered that in 64%
565
00:39:39,920 --> 00:39:44,000
of all songbird species,
females sing.
566
00:39:45,040 --> 00:39:47,120
And that, in the distant past,
567
00:39:47,120 --> 00:39:49,360
the ancestors of all songbirds
568
00:39:49,360 --> 00:39:52,920
would have had both male
and female singers.
569
00:39:57,480 --> 00:40:02,040
When birdsong began,
perhaps all female birds sang.
570
00:40:05,440 --> 00:40:08,400
So why don't all female
birds sing today?
571
00:40:10,240 --> 00:40:12,040
The answer is migration.
572
00:40:13,960 --> 00:40:18,200
Male migrants like the nightingale
arrive in their breeding grounds
573
00:40:18,200 --> 00:40:22,560
before the female. They set
up and defend the breeding
574
00:40:22,560 --> 00:40:25,880
territories, so the females
don't need to sing.
575
00:40:28,400 --> 00:40:32,240
In species that don't migrate,
like the lyrebird and fairy wren,
576
00:40:32,240 --> 00:40:35,200
then often the females
will have their own territory.
577
00:40:39,320 --> 00:40:41,240
And they will sing to defend it.
578
00:40:44,800 --> 00:40:48,880
This female song challenges the way
scientists have thought about
579
00:40:48,880 --> 00:40:51,920
sexual selection for
the last hundred years.
580
00:40:53,000 --> 00:40:55,320
This recent discovery
is a paradigm shift.
581
00:40:55,320 --> 00:40:57,200
It's extremely exciting,
582
00:40:57,200 --> 00:40:59,280
and it really forces us again
583
00:40:59,280 --> 00:41:03,000
to reconsider what we think
of as birdsong.
584
00:41:04,960 --> 00:41:08,560
Birdsong was fundamental to
the formulation of Darwin's theory
585
00:41:08,560 --> 00:41:10,040
of sexual selection,
586
00:41:10,040 --> 00:41:12,880
and the discovery that females sing
as well
587
00:41:12,880 --> 00:41:15,040
makes us challenge that theory.
588
00:41:16,760 --> 00:41:20,560
Because our perception
of birdsong has been biased
589
00:41:20,560 --> 00:41:22,880
towards the northern hemisphere,
590
00:41:22,880 --> 00:41:27,480
we have been unaware of some
of the most thrilling bird songs
591
00:41:27,480 --> 00:41:30,440
on the planet,
but that view is changing.
592
00:41:34,760 --> 00:41:38,160
Our understanding of song
is continually developing,
593
00:41:38,160 --> 00:41:40,800
and all the time we're
learning new things.
594
00:41:40,800 --> 00:41:45,080
It's a mystery that needs real
research to unravel it,
595
00:41:45,080 --> 00:41:47,000
and we're still learning.
596
00:41:49,120 --> 00:41:52,720
How exciting it is to think
of the discoveries
597
00:41:52,720 --> 00:41:55,400
that are about to be made
about birdsong.
598
00:42:06,000 --> 00:42:10,480
This next ground-breaking recording
reminds us just how thrilling
599
00:42:10,480 --> 00:42:12,760
those new discoveries could be...
600
00:42:14,760 --> 00:42:19,280
..because it revealed to us
an entirely different world of song.
601
00:42:23,520 --> 00:42:29,120
Few animal songs are more beautiful
than the ones that are recorded
602
00:42:29,120 --> 00:42:34,320
on this disc, and yet had it not
been for recent technological
603
00:42:34,320 --> 00:42:38,720
advances, we would never have known
that such songs existed.
604
00:42:42,000 --> 00:42:44,640
The waters off the coast of Bermuda.
605
00:42:45,720 --> 00:42:49,880
US Navy engineers are using
underwater microphones called
606
00:42:49,880 --> 00:42:53,480
hydrophones to listen
for enemy submarines.
607
00:42:54,880 --> 00:42:56,880
This is what they pick up.
608
00:42:57,960 --> 00:43:00,360
LOW GROWLING
609
00:43:02,480 --> 00:43:06,760
It's not a submarine or indeed
any kind of man-made noise.
610
00:43:10,720 --> 00:43:14,840
I'll always remember the first
time I heard those songs.
611
00:43:16,360 --> 00:43:19,680
It brought back to my mind
the stories of sailors
612
00:43:19,680 --> 00:43:21,560
in the old sailing ship days
613
00:43:21,560 --> 00:43:23,280
out at sea in their bunks,
614
00:43:23,280 --> 00:43:27,480
hearing those wonderful, eerie
sounds resonating through the ship.
615
00:43:29,080 --> 00:43:32,840
It didn't come, of course, from
a mermaid, but something perhaps
616
00:43:32,840 --> 00:43:37,960
even more extraordinary - a gigantic
creature weighing many tonnes.
617
00:43:37,960 --> 00:43:39,040
A whale.
618
00:43:40,640 --> 00:43:42,360
WHALE SONG
619
00:43:47,120 --> 00:43:52,000
Almost unbelievably, this was
the first time that anyone had ever
620
00:43:52,000 --> 00:43:54,400
identified the sound of a whale.
621
00:43:56,520 --> 00:44:00,160
When biologist Dr Roger Payne
heard it, he was thrilled.
622
00:44:01,960 --> 00:44:07,560
It was back in 1967 about that I met
a fellow named Frank Watlington,
623
00:44:07,560 --> 00:44:09,240
who became a great friend,
624
00:44:09,240 --> 00:44:12,440
and he played a sound to me
of humpback whales.
625
00:44:13,840 --> 00:44:15,760
WHALE SONG
626
00:44:15,760 --> 00:44:20,360
It was the most beautiful thing
I had ever heard from nature.
627
00:44:29,080 --> 00:44:33,800
The first time I ever went swimming
with a whale that was singing,
628
00:44:33,800 --> 00:44:38,360
it's such an incredible experience,
it's completely shattering.
629
00:44:41,600 --> 00:44:45,440
It feels like, when you get
close to one, that something
630
00:44:45,440 --> 00:44:48,200
has put its hands on your chest
and is shaking you
631
00:44:48,200 --> 00:44:50,080
until your teeth rattle.
632
00:44:50,080 --> 00:44:53,560
My first thought was, I wonder
if I can stand this, I wonder
633
00:44:53,560 --> 00:44:56,800
if this is actually going
to kill me somehow.
634
00:45:01,120 --> 00:45:05,040
The question was, would we call
these sounds songs?
635
00:45:07,920 --> 00:45:10,080
Some were short, like birdcalls,
636
00:45:10,080 --> 00:45:11,680
but others were longer,
637
00:45:11,680 --> 00:45:13,440
some up to half an hour.
638
00:45:19,920 --> 00:45:23,400
Speeded up, this is what
they sounded like.
639
00:45:23,400 --> 00:45:25,640
HIGH-PITCHED SONG
640
00:45:28,960 --> 00:45:31,320
They sounded like birdsong.
641
00:45:34,240 --> 00:45:36,200
Roger called them songs.
642
00:45:43,920 --> 00:45:48,320
In the late 1970s, I too went
swimming with humpback whales.
643
00:45:51,320 --> 00:45:55,800
I remember seeing this creature
below me and then hearing its song.
644
00:45:55,800 --> 00:45:58,000
EERIE WHOOPING
645
00:46:01,080 --> 00:46:05,680
It was thought they sing
for the same reason as birds -
646
00:46:05,680 --> 00:46:09,400
males singing to rivals
and potential mates.
647
00:46:11,400 --> 00:46:14,480
But no-one has ever seen
a female listening.
648
00:46:17,080 --> 00:46:20,520
In truth, no-one really knows
why whales sing.
649
00:46:23,840 --> 00:46:28,640
But one thing is certain - the sound
of their song saved them from us.
650
00:46:31,080 --> 00:46:36,120
In 1970, Roger released an album
called Songs Of The Humpback Whale.
651
00:46:37,680 --> 00:46:40,840
At the time, we had been
killing whales,
652
00:46:40,840 --> 00:46:42,880
mainly for their oil, for centuries.
653
00:46:47,400 --> 00:46:51,720
We were very close to exterminating
them out of sheer greed.
654
00:46:53,480 --> 00:46:55,480
Then we heard their song.
655
00:47:00,000 --> 00:47:05,040
Whole bunches of people in several
countries began making organisations
656
00:47:05,040 --> 00:47:09,440
to save the whales and the Save
the Whales movement was born,
657
00:47:09,440 --> 00:47:12,200
and in many ways that
was sort of the beginning
658
00:47:12,200 --> 00:47:14,320
of the conservation movement.
659
00:47:19,360 --> 00:47:23,440
The conscience of the world was
woken by this song of the whale.
660
00:47:24,960 --> 00:47:27,760
We heard it just in time
to save them.
661
00:47:27,760 --> 00:47:29,640
ECHOING SHRIEK
662
00:47:32,320 --> 00:47:35,120
But for my next and final singer,
663
00:47:35,120 --> 00:47:37,200
there was no such reprieve.
664
00:47:39,080 --> 00:47:40,600
BIRDSONG
665
00:47:46,000 --> 00:47:50,120
There are few songs
more haunting than this.
666
00:47:56,120 --> 00:48:01,200
It's a male Hawaiian 'o'o bird
calling for a mate.
667
00:48:04,160 --> 00:48:06,480
But is he singing into silence?
668
00:48:08,520 --> 00:48:09,720
Habitat destruction
669
00:48:09,720 --> 00:48:13,680
and the introduction of invasive
species have decimated
670
00:48:13,680 --> 00:48:17,720
many Hawaiian
songbirds, including the 'o'o.
671
00:48:19,320 --> 00:48:23,880
It may well be that by the time
this recording was made,
672
00:48:23,880 --> 00:48:26,520
there were no females left alive.
673
00:48:27,800 --> 00:48:33,680
It's the sound of a male singing
for a mate who no longer exists.
674
00:48:36,240 --> 00:48:39,840
The 'o'o has since been
declared extinct.
675
00:48:43,320 --> 00:48:48,160
He was the last of an entire bird
family found nowhere else on Earth.
676
00:48:48,160 --> 00:48:49,680
Now gone.
677
00:48:52,720 --> 00:48:58,520
There is no more dramatic reminder
of this loss than this sound.
678
00:48:58,520 --> 00:49:00,560
BIRDSONG
679
00:49:13,320 --> 00:49:17,520
And how many more songs have we lost
in other parts of the planet?
680
00:49:19,720 --> 00:49:23,880
Here in Britain, it's estimated
that 38 million birds
681
00:49:23,880 --> 00:49:28,160
have disappeared from our skies
in the last 60 years.
682
00:49:28,160 --> 00:49:30,520
One in five gone.
683
00:49:33,920 --> 00:49:37,040
Climate change, habitat
deterioration
684
00:49:37,040 --> 00:49:40,640
and the resulting
decrease in food and other resources
685
00:49:40,640 --> 00:49:42,880
are thought to be the main factors
686
00:49:42,880 --> 00:49:45,280
behind this catastrophic decline.
687
00:49:47,280 --> 00:49:50,720
It's now up to us to decide how many
more songs
688
00:49:50,720 --> 00:49:51,800
we will allow
689
00:49:51,800 --> 00:49:53,360
to fade into silence.
690
00:50:03,360 --> 00:50:06,800
These songs enrich our lives, too.
691
00:50:06,800 --> 00:50:11,040
They're surely amongst
the loveliest in the universe.
692
00:50:11,040 --> 00:50:16,760
And without them, our lives
would truly be impoverished.
693
00:50:16,760 --> 00:50:21,520
And what is lost when the songs
fall silent is more than just
694
00:50:21,520 --> 00:50:26,360
an enchanting operatic backdrop
to our own lives,
695
00:50:26,360 --> 00:50:31,480
because for the creatures that sing
them, songs are far more than that.
696
00:50:33,280 --> 00:50:35,080
They are a weapon of war...
697
00:50:36,240 --> 00:50:40,760
..a serenade, a promise
of parenthood, a daring deceit...
698
00:50:42,800 --> 00:50:45,800
..or perhaps something
even more astonishing
699
00:50:45,800 --> 00:50:47,840
that we are yet to discover.
700
00:50:49,600 --> 00:50:54,360
Each one a marvellous example of
the spectacular survival strategies
701
00:50:54,360 --> 00:50:57,840
that animals have developed
in order to stay alive.
702
00:50:57,840 --> 00:50:59,720
WHALE SONG
703
00:50:59,720 --> 00:51:02,440
That is why I'll never cease
to wonder at
704
00:51:02,440 --> 00:51:04,000
the beautiful sounds
705
00:51:04,000 --> 00:51:05,760
we call song.
706
00:51:07,840 --> 00:51:09,800
CHIRPING
707
00:51:28,960 --> 00:51:32,680
Few sounds of nature are
more beloved by this nation
708
00:51:32,680 --> 00:51:35,400
than that of the nightingale.
709
00:51:35,400 --> 00:51:38,440
And there's one more recording
of it that I have memories
710
00:51:38,440 --> 00:51:40,400
of listening to as a child.
711
00:51:41,640 --> 00:51:47,280
It was made by the BBC two years
before I was born, in May 1924.
712
00:51:48,400 --> 00:51:52,920
It's a cello accompanied
by a nightingale.
713
00:51:52,920 --> 00:51:55,880
In this country,
it was ground-breaking.
714
00:51:58,640 --> 00:52:04,600
It is, in fact, the first live
broadcast of any wild animal song.
715
00:52:10,640 --> 00:52:15,320
The idea came from a celebrated
cellist called Beatrice Harrison.
716
00:52:17,680 --> 00:52:21,640
RECORDING: One night when
I'd been playing for hours,
717
00:52:21,640 --> 00:52:24,640
I suddenly heard the note
718
00:52:24,640 --> 00:52:28,120
of the most heavenly bird,
719
00:52:28,120 --> 00:52:32,880
and it struck me how lovely it
would be if he could be broadcast.
720
00:52:36,480 --> 00:52:40,600
The nation held its breath
while Beatrice played.
721
00:52:40,600 --> 00:52:45,040
It was the first time
that the wild world of nature
722
00:52:45,040 --> 00:52:47,280
came straight into your living room.
723
00:52:50,960 --> 00:52:55,360
Perhaps a million listeners tuned
in to that first broadcast.
724
00:52:58,840 --> 00:53:02,920
It was so popular, the BBC
made it an annual event.
725
00:53:05,720 --> 00:53:10,640
The performance became so celebrated
that Beatrice was asked to recreate
726
00:53:10,640 --> 00:53:14,120
it for a 1943 film
with Sir Laurence Olivier.
727
00:53:14,120 --> 00:53:16,320
CELLO PLAYS
728
00:53:19,200 --> 00:53:21,000
BIRD CALLS
729
00:53:28,160 --> 00:53:31,640
It was far from the first time,
of course, that the nightingale
730
00:53:31,640 --> 00:53:33,880
had made a cultural appearance.
731
00:53:35,040 --> 00:53:40,800
The nightingale has inspired poets
and musicians for ages, and perhaps
732
00:53:40,800 --> 00:53:45,320
the most famous poem of all
is by John Keats.
733
00:53:46,600 --> 00:53:50,160
Thou was not born for death,
immortal Bird!
734
00:53:50,160 --> 00:53:54,080
No hungry generations tread
thee down,
735
00:53:54,080 --> 00:53:58,040
The voice I hear this
passing night was heard
736
00:53:58,040 --> 00:54:01,400
In ancient days
by emperor and clown.
737
00:54:03,320 --> 00:54:07,800
Keats wrote those lines
in Hampstead in London,
738
00:54:07,800 --> 00:54:11,360
but he wouldn't hear
a nightingale there today.
739
00:54:17,800 --> 00:54:20,640
There are no nightingales
in London now.
740
00:54:21,920 --> 00:54:26,440
In fact, we've lost over 90%
of nightingales in this country
741
00:54:26,440 --> 00:54:28,280
in the last 50 years.
742
00:54:31,440 --> 00:54:32,640
What a tragedy.
743
00:54:36,120 --> 00:54:38,880
The causes are still not
fully understood...
744
00:54:40,760 --> 00:54:45,160
..but habitat deterioration probably
played a significant part.
745
00:54:51,240 --> 00:54:54,960
In one small corner of Britain,
however, there is a place trying
746
00:54:54,960 --> 00:54:58,120
to provide the nightingale
with a safe haven.
747
00:54:59,680 --> 00:55:06,000
The Knepp Estate in West Sussex -
3,500 acres that was once farmland.
748
00:55:07,920 --> 00:55:12,200
But the soil here wasn't suited
to modern-day intensive agriculture.
749
00:55:13,640 --> 00:55:17,200
Since 2001,
it's been left to nature.
750
00:55:19,680 --> 00:55:24,800
There aren't many rewilding projects
in Britain as pioneering as this.
751
00:55:28,680 --> 00:55:30,480
Wildlife now thrives here...
752
00:55:34,840 --> 00:55:38,120
..including some of the country's
rarest species.
753
00:55:43,720 --> 00:55:46,160
CUCKOO CALL
754
00:55:46,160 --> 00:55:49,840
This, for many of Britain's
best-loved songbirds,
755
00:55:49,840 --> 00:55:52,920
is an ideal place
for shelter and food.
756
00:55:58,760 --> 00:56:02,840
The nightingale is one of many
species found at Knepp.
757
00:56:04,640 --> 00:56:08,280
Here, dense, almost
impenetrable thorny scrub
758
00:56:08,280 --> 00:56:10,760
provides their ideal nesting site.
759
00:56:16,560 --> 00:56:21,320
Today, it's late spring and one nest
of chicks is being ringed.
760
00:56:24,800 --> 00:56:28,560
This makes it possible to gather
vital information that can help
761
00:56:28,560 --> 00:56:30,520
monitor population numbers.
762
00:56:34,760 --> 00:56:38,280
There are estimated to be more
than 40 nightingale territories
763
00:56:38,280 --> 00:56:40,240
in this area of the estate.
764
00:56:44,200 --> 00:56:46,680
Back when it was intensively farmed,
765
00:56:46,680 --> 00:56:48,480
there were only nine.
766
00:56:49,680 --> 00:56:52,760
Few places in Britain have
nightingales increasing
767
00:56:52,760 --> 00:56:54,080
in such numbers.
768
00:56:58,480 --> 00:57:01,880
It gives us hope, perhaps,
that the British countryside
769
00:57:01,880 --> 00:57:05,200
could once more be filled
with the nightingale's
770
00:57:05,200 --> 00:57:07,720
beautiful and iconic song.
771
00:57:13,760 --> 00:57:19,480
How wonderful it would be if each of
us could say we've heard the songs
772
00:57:19,480 --> 00:57:23,120
of the Earth and we've saved them.
773
00:57:23,120 --> 00:57:25,360
BIRDSONG
774
00:57:32,200 --> 00:57:34,240
WHALE SONG
775
00:57:51,440 --> 00:57:54,800
BIRD AND WHALE SONG
94583
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.