七个世界，一个星球（2019）

虎皮鹦鹉发展出一套简单高效的防御体系
The budgies have a simple but very effective defence -
它们会同时升空
they all take to the wing at once.
空中猎手必须锁定猎物几秒钟
An aerial hunter needs to lock on to a single target for a few seconds
才能一击而中
if it is to catch it,
但面对上下翻飞的虎皮鹦鹉 做到这点难如登天
but in this swirl, that's very hard to do.
群体行动能保护个体安全 但喝水的欲望根本无法抑制
Flying in a flock keeps the budgies safe, but they're still desperate to drink.
当一只胆大的虎皮鹦鹉俯冲时 其它成员也蜂拥而下
As soon as a particularly brave one takes the plunge, they all do.
可是在水面 它们更容易遭到攻击
But once on the water, they are easier to target.
它们必须快速喝水 并保持行动一致
They must drink quickly and stick together.
最后一批离开的成员面临的危险也最大
The last ones to leave will be the ones in most danger.
浩浩荡荡的虎皮鹦鹉大军中 只有一只被擒
Only one has been taken from a flock of 10,000.
几天后 它们将离开这个地区
In a few days, they will leave the area,
继续踏上寻觅之旅
on their never-ending search
寻找新的大饱口福的机会
for the next brief opportunity to feed and drink.
澳大利亚大♥陆♥继续向北漂移
As the continent continued to drift north,
最终进人温暖的热带海洋
it eventually entered warm, tropical seas.
在波光粼粼的清澈海水中
And here, in the crystal-clear, sunlit water,
在水下大约一两米深处
just a metre or two beneath the surface,
是一派生机勃勃的景象
life proliferated.
珊瑚茁壮成长 在浅水海域形成了珊瑚礁
Coral grows into reefs in these shallow seas.
这里是宁格罗暗礁群
This is Ningaloo...
是世界上不计其数的海洋物种赖以栖息的家园
...today one of the richest anywhere in the world.
成千上万的鱼类和其它各种海洋居民
Thousands of species of fish and all kinds of other organisms
在这些珊瑚城市繁衍生息
thrive in these coral cities.
它们吸引了地球上现存最古老的捕食者之一
And they have attracted the most ancient of living predators.
鲨鱼
Sharks.
它们存在的历史比恐龙还要久远两亿多年
They were around 200 million years before the dinosaurs.
鲨鱼行动迅速 灵活敏捷
They're fast and agile,
捕食小型珊瑚礁鱼类游刃有余
well able to pick off the small reef fish.
但它们此行是为了更大的回报
But they come here for bigger rewards.
这些规模宏大的鱼群从开阔海域成群而来
These are fish from the open ocean,
出于某种原因 它们经常游过珊瑚礁
and every so often, for some reason, they swim over the reef.
鱼群就像虎皮鹦鹉一样快速旋转
The small fish swirl like the budgies, and for the same reason.
这种集体战略让捕食者晕头转向 难以锁定目标
It makes it harder for a hunter to single out a particular target.
鲨鱼改变分而攻之的做法 不再执着于个体
But, in fact, the sharks aren't trying to catch them individually.
它们将鱼群赶向近岸水域 防止它们四散而逃
They're driving them closer to the shore, penning them against the beach.
鲨鱼从容不迫地将鱼群赶向浅水区
Slowly, the sharks drive each new wave of fish into shallow water,
饵球变得越来越大
and the bait ball grows.
更多鲨鱼闻风而至 有些来自数公里之外
More sharks arrive, some from many miles away.
但是鲨鱼群仍旧按兵不动
And still the sharks don't attack.
它们正在等待
They're waiting...
最佳的进攻时机
...for the right moment.
数百万只鱼被困在浅水区域 进退两难
Millions of fish are now trapped in these shallow waters.
像这样的盛况十年难得一见
It only happens like this once in every decade or so.
进攻的号♥角终于吹晌
The time has come to strike.
对鲨鱼来说 这是大快朵颐的机会
For the sharks, this is a bonanza.
它们联♥合♥行♥动♥
They work together.
每只鲨鱼可以轮流进食
Each shark now fills its stomach.
这片浅水区域俨然成了鲨鱼的天下
These shallow seas are exceptionally rich in sharks.
鲸鲨每年都会聚集在这个地方
There are more species here than anywhere else on Earth.
澳大利亚四面环水 大♥陆♥♥四♥周不仅环绕着美丽多姿的珊瑚礁
Australia is not only fringed by rich reefs
还点缀着大大小小的奇特岛屿
but girdled with islands - some big, some small.
澳大利亚的南部海岸坐落着该国目前最大的岛屿
Off the south coast lies by far the biggest of them.
塔斯马尼亚岛
Tasmania.
岛上栖息着当地特有的有袋动物
And that has its own special marsupial...
这种动物喜欢在夜幕降临后现身
...one that seldom appears until after dark.
袋獾
The Tasmanian devil.
许多捕食者的领地中不乏猎物
Many predators inhabit a territory packed with prey.
但是在塔斯马尼亚岛 它们的猎物寥寥无几
But here, there's nothing like that for them.
袋獾可能要“夜以继夜”地跋涉数公里
Each may travel for miles night after night,
沿途找食任何活物或腐尸
prepared to eat anything it can find, dead or alive.
海岸地带是理想的觅食地
The shoreline is a good place to search.
它们在这里也许能找到小型动物
There might be some small creatures to catch here,
或者享受潮汐送来的免费大餐
or maybe something that the tide has brought in.
一只沙袋鼠的尸体残骸被冲上海岸
The carcass of a wallaby has been washed ashore.
袋獾一次能吃掉相当于自身体重40%的猎物
Tasmanian devils can eat 40% of their body weight in one session,
它们的颚骨强劲有力
and they have hugely powerful jaws.
不会浪费任何食物 包括骨头
They tackle everything - even bones.
回到巢穴
Back at the den,
它还要喂食嗷嗷待哺的幼崽
there are other hungry mouths.
它的两只幼崽刚刚6个月大
Her two youngsters are six months old.
它们的主食仍旧是母乳 此刻它们早已饥饿难耐
They still rely on their mother's milk, but they're feeling peckish!
在等待母亲返回哺乳时 它们自己必须
There must be something solid they could find for themselves
独♥立♥找到一些固体食物
while they're waiting for a drink.
这东西能吃吗
Is this food?
袋貂看起来非常诱人
That possum smells tasty...
可惜高不可攀
...but it's a little high up.
这个倒是胜算更大一些
This looks more promising.
辛苦没有白费 它找到了一根树枝
At last, a giant stick!
初次尝试 算不错了
Not bad for a first go.
它们可以继续跟着母亲3个月 享受饭来张口的生活
Their mother will protect and feed these youngsters for another three months.
幼崽的生存不仅对袋獾母亲 甚至对我们都至关重要
Their survival is important to her, but also for us...
因为全球现存的袋獾数量已经少得可怜
...because these are one of the last devil families in the world.
袋獾现在属于濒危物种
Tasmanian devils are now endangered...
仅存在于少数偏远荒凉的地区
...found in only a few places,
比如塔斯马尼亚海岸的这座偏远小岛
such as this remote islet off the coast of Tasmania.
但它们曾经遍布澳大利亚各地
But they once lived across the whole of Australia.
我们已经找到了相关证据
Evidence that this was so
就在距离袋獾的巢穴大约4000公里之外的地方
can be seen nearly 2,500 miles away from the devils' family den,
在澳大利亚的北部海岸
on Australia's northern coast.
这里地势高低起伏 巨石林立
This great stretch of boulders
岩石表面镌刻着世界上密度最高的史前画面
is covered by the largest concentration of prehistoric images anywhere in the world.
这些岩石上有上百万幅野生动物壁画
Over one million pictures of wildlife...
其中就包括
...and among them...
袋獾
...a Tasmanian devil.
这些是大约60000年前
It was engraved on stone 60,000 years ago
第一批到达澳大利亚大♥陆♥的原住民雕刻在石头上的
by some of the first human beings to reach the continent.
大约200年前
Then, just 200 years ago,
欧洲殖民者带着长枪短炮进入澳大利亚 随之带来的还有狗 狐狸和猫
European settlers arrived with guns and dogs, foxes and cats.
这些因素导致许多本土动物走向灭绝
Together, they decimated Australia's unique wildlife.
这曾经是澳大利亚大♥陆♥最大的捕食者之一
This was one of the continent's biggest animal predators -
也就是所谓的袋狼
a marsupial wolf, or thylacine.
人们早在1936年拍摄到过
The last-known remaining one was filmed in 1936
动物园里的最后一只袋狼
in a zoo just before it died...
随着他的死亡 这个物种从我们的地球上彻底销声匿迹
...and so brought the final extinction of its species.
这些岩石就是它们的纪念碑
These rocks are now its memorial.
而袋獾可能也会步其后尘 遭遇同样的命运
And they may become that for the Tasmanian devil as well.
澳大利亚哺乳动物的消失速度之快 远远超过其它任何地方
Mammals in Australia are disappearing faster than anywhere else on Earth.
它们当初适应了自然家园的改变 成功幸存
They succeeded in adapting to life as their home changed around them.
但是现在它们却面临生命中最大的挑战
But now they face their greatest challenge -
那就是应对人类带来的影响
the change to their world brought by humanity.
在接下来的数十年里 这些独特物种的命运
Which of its unique species will survive the coming decades
就完全掌握在我们人类手中
now depends on us.
下集预告 一个人类改造的世界
Next time - a world transformed by mankind...
总能在意想不到的地方
...where extraordinary animals are found...
发现各种非凡的动物
...in surprising places.
欧洲
Europe.