地球之声（2024）

南非的沙漠
The deserts of Southern Africa.
画 外 音
汤 姆 · 希 德 斯 顿
这是一个沉默是金的世界
This is a world where silence is golden.
但仔细听
But listen carefully…
就会听到这些寂静的土地充满了
and these hushed lands are alivewith secret conversations
我们才刚开始了解的秘密对话
we're only beginning to understand.
对于一个小小的沙漠居民来说
And for one little desert dweller,
隐藏的信息是保证家族成员安全的关键
hidden messages are keyto keeping their family safe.
它就是猫鼬
Meerkats.
这些健谈的动物把大部分醒着的时间都用于
These chatty creaturesspend most of their waking hours
挖掘昆虫和幼虫
digging for insects and grubs.
有些猫鼬比其他的更仔细
Some more carefully than others.
但由于它们的头埋在沙子里不可能发现危险
But with their heads buried in the sand,it's impossible to spot danger.
所以猫鼬进化出了…
So meerkats have evolved
一个巧妙的警报系统
an ingenious alarm system.
它们的吱吱叫声听起来可能很简单但放慢叫声的速度…
Their squeaks may sound simple,but slowing them down…
揭示出它们在嘴巴不动的情况下会发出不同的叽喳声
reveals different chirpsmade without moving their mouths.
它们将这些组合起来创造了30个不同的短语
They combine theseto build 30 distinct phrases.
这种复杂的语言比许多灵长类动物的语言还要复杂
This sophisticated language,more complex than that of many primates,
使它们能够互相警告特定的掠食者
allows them to alert each otherto specific predators.
一只战雕
A martial eagle.
非洲最大的猛禽
Africa's largest bird of prey,
这只是猫鼬每天都会遇到的危险之一
and just one of the perils meerkatscome across every day.
这只年轻雄性正在值班放哨
This young male is on lookout duty.
它花了六个月的时间学习猫鼬语言
He's spent six monthslearning meerkat language,
现在必须用它让家族成员知道周围发生了什么
and must now use it to let his family knowwhat's going on around them.
这是警报解除的叫声
This is the all-clear call.
它的意思是“继续挖 没什么可担心的”
It means, "Keep digging.Nothing to worry about."
但当你只有0.3米高时
But when you're just one foot tall,
危险不仅仅来自上面
danger doesn't only come from above.
一条黄金眼镜蛇 它的毒液可以杀死猫鼬
A Cape cobra.Its venom could kill a meerkat.
放哨的猫鼬发出了当心蛇的警报
The lookout barks the snake warning,
但令人惊讶的是家族成员并没有逃避威胁
but surprisingly, the family doesn'trun away from the threat.
它们反而奔向它
They run towards it.
通过继续发出叫声
By continuing to call,
越来越多的猫鼬加入攻击行列
more and more join the assault.
安全赶走了眼镜蛇
Safely seen off…
放哨员再次解除警报
and once again,the lookout gives the all-clear.
但科学家们正在发现猫鼬的语言
But scientistsare discovering meerkat language
比仅仅识别不同的掠食者要复杂得多
is far more complexthan just identifying different predators.
令人惊奇的是它们还可以传达威胁的紧迫性
Amazingly, they can also communicatethe urgency of a threat.
战雕正在狩猎
The martial eagle is on the hunt.
距离还很远 可能只会从它们身边飞过
It's still a long way off,and may just pass them by.
放哨员发出了低紧迫性空中警报
The lookout soundsthe low-urgency aerial alarm.
但战雕正在渐渐逼近
But the eagle is edging closer.
是时候提高紧迫性了
Time to shift things up a gear.
中等紧迫性警报
A medium-urgency alarm.
无需惊慌但听到警报的每只猫鼬现在都停下来
No need to panic,but everyone in earshot now stops.
并将目光投向战雕
And puts eyes on the eagle.
最后 高度戒备的叫声
Finally, the high-alert call.
所有猫鼬都向洞穴冲去
Everyone makes a dash for the burrow.
今天猫鼬家族都大难逃生了
Today,the whole family lives to tell the tale.
这一切都归功于我们年轻的放哨员
And it's all thanksto our young lookout's mastery
对猫鼬语言的熟练掌握
of meerkat language.
它们的语言远比我们想象的复杂
Far more sophisticatedthan we ever realized.
与猫鼬的家园接壤
Bordering the meerkat's home
在干旱的喀拉哈里沙漠
in the arid Kalahari…
是地球上最古老的沙漠
lies the oldest desert on the planet.
纳米布沙漠
The Namib.
这是一片广阔的沙丘之海有的高达300多米
A vast sea of dunes,some a thousand feet tall.
在这个舞台上 即使最微弱的脚步声
A stage where the faintest footsteps…
也可能暴露你的行踪
can give you away.
但在这里 发出神秘声音的不仅仅是动物
But out here, it's notonly animals that make secretive sounds.
当沙漠之风吹过沙丘顶部时
When the desert windsblow over the crests of the dunes…
它们会引发沙崩
they trigger an avalanche of sand.
麦克风捕捉到了…
Microphones capture the tiny sounds
当沙粒开始翻滚…
as the grains tumble over each other…
和振动时的微小声音
and start to vibrate.
数以万亿计的沙粒一起振动
Trillions of sand particlesvibrating together
使沙丘表面像巨型扬声器一样产生共鸣
cause the surface of the dune to resonatelike a giant speaker.
被称为纳米布的鸣沙沙丘
Known as the singing dunes of the Namib,
这种星球的嗡嗡声已经持续了一百多万年
this planetary hum has been buzzingfor more than a million years.
但这里有一些我们听不到的噪音
But there are some noises out herethat are beyond our hearing.
动物用来远距离保持联♥系♥的
Secret channels of soundthat animals use to keep in touch
秘密声音频道
over vast distances.
非洲象
The African elephant…
像大喷气机一样吵闹
as loud as a jumbo jet.
它们的吼叫声可达到120分贝
Their bellowing trumpetsreach 120 decibels.
但它们也使用低沉的咕噜声
But they also use low-pitched rumbles
与远处的象群保持联♥系♥
to keep in touch with distant herds.
低沉的声音传得更远
Deeper sounds travel further,
但我们只听到了它们交流的一小部分
but we only hear a fractionof what they're saying.
采用尖端技术
Using cutting-edge technology,
我们可以聆听大象最低沉的咕噜声这是前所未有的
we can tune in to the very lowest rumblesof elephants like never before.
被称为次声波的部分
Known as infrasound…
是它们叫声中我们通常听不到的现在能听到了
we're now hearing the partsof their calls usually inaudible to us.
它们发出这些最低的声音
They create these lowest of sounds
通过将空气吹过巨大的声带
by blowing air across giant vocal cords
它们的声带比我们的大八倍
eight times larger than ours.
这些低音的传播范围会超过260平方公里
These can broadcastfor over 100 square miles.
它使象群能够在广阔的平原上保持联♥系♥
It allows herds to keepin touch across these vast plains.
更重要的是当它们感觉到危险时能聚集起来
And more importantly,to join forces when they sense danger.
这里是狮子的地盘
This is lion country.
最大的狮群可以捕获幼象
The largest pridescan take down young elephants.
在沙漠中 非洲最大的掠食者汇聚到
In the desert,Africa's biggest predators gather close
几个水坑旁边
to the few water holes…
它们知道所有猎物最终都必须来喝水
where they knowall prey must eventually come to drink.
为了到达水源 象群必须弄清楚
To get to water, the herd must figure out
有多少只狮子
how many lions there are,
以及它们是否对小象构成风险
and whether they pose a riskto their calves.
它们只需聆听就可以知道
They can do this simply by listening.
大象偷听狮子的领地叫声
Elephants eavesdropon lions' territorial calls.
甚至还学会了数数
And have even learned to count.
如果感到受到威胁 就围住小象们
Huddling around youngstersif they feel threatened…
60岁以上最聪明、最年长的大象
the wisest and oldest elephantsover 60 years of age
还可以区分母狮的叫声…
can also distinguishbetween the calls of lionesses…
和更危险的雄狮发出的更低沉、更大声的咆哮
and the deeper,louder roars of more dangerous males.
如果狮子太多 大象就会避开水坑
If there are too many lions,the elephants will avoid the water hole.
但当它们的数量超过掠食者
But when they outnumber the predators,
它们不怕向敌人展示谁是老大
they're not afraidto show them who's boss.
狮子被赶走后 象群就可以喝水了
With the lions sent packing,the herd gets to drink.
通过聆听声音的世界我们才刚刚开始了解
By dialing into a world of sound thatwe're only just beginning to understand,
大象如何在这些广阔的平原上保护家族成员的安全
elephants keep their families safeacross these vast planes.
对于其他沙漠居民来说成功并非来自于聆听
For other desert inhabitants,success comes not from listening
遥远的声音
to distant sounds…
而是聆听脚下传来的微弱杂音
but to minuscule murmursjust beneath their feet.
蝙蝠耳狐
The bat-eared fox.
无奖竞猜它们的名字是怎么来的
No prizes for guessinghow they got their name.
它们称为“耳廓”的外耳高约13厘米
Their outer ears, known as "pinna,"are five inches tall
就像卫星天线一样
and act like satellite dishes
使这些小巧的狐狸成为沙漠中终极的依靠声音的掠食者
making these dainty little foxesthe desert's ultimate acoustic predators.
天色已晚 这个家族正准备去打猎
In the last light of day,this family is getting ready to hunt.
这意味着要聆听沙漠最细微的声音
And that meanstuning into the desert's quietest sounds.
收割者白蚁是狐狸最喜欢的零食
Harvester termites,the fox's favorite snack.
不比蚂蚁大
No bigger than an ant,
奇怪的是 白蚁的脚步声要安静100倍
strangely, a termite's footstepsare 100 times quieter.
它们似乎无法被发现
They may seem impossible to detect.
但蝙蝠耳狐拥有声音方面的超能力
But the bat-eared foxhas a sonic superpower
并用其超大的耳朵来放大最微小的声音
and uses its oversized earsto amplify the tiniest sounds.
超灵敏度麦克风揭示出狐狸如何听到猎物的声音
Ultra-sensitive microphones givean insight into how a fox hears its prey.