绿色星球（2022）

而且上面布满了倒刺
..and they're covered with backward-pointing barbs.
所以即使用镊子把刺拔♥出♥来♥也是很困难的
So getting them out, even with a pair of pliers, is quite hard.
被扎到可就太难受了
This is not pleasant at all.
没有工具很难弄掉
It won't come off, or without.
哦 看这个！
Oh, look at that!
很少有植物具备如此强大的防御能力
It's hard to imagine a more aggressive defence than this,
它使植物及其芽都变得不易受到伤害
and it makes both the plant and its buds virtually invulnerable.
大多数动物都知道一定要跟它保持距离
Most animals know to keep clear.
它的果实就像一个个小圆桶 从顶部长出
Cholla buds grow like tiny barrels from the top of the adult plant
然后掉落到地上
and then drop off.
如果它在原地生根发芽
If the young cholla put down roots here,
就会跟母株争抢水资源
it would compete with its parent for water.
夜幕降临
Night falls...
这棵果实要上路了
..and this one is on the move.
一只白喉林鼠 它知道如何对付圆柱掌的果实
A pack rat. She knows how to deal with a cholla.
它会避开刺 咬住果实断裂的部位
She avoids the spines by gripping it at the place
并拖动果实
where it broke off from its parent.
它的行动相当迅速
And she works fast.
这里有群鼠猎人
There are pack rat hunters here.
白喉林鼠喜欢用带刺的果实在巢穴周围筑起围墙
She uses the cholla to build a spiny wall around her nest.
它还会啃食果肉来补充水分
The flesh of the cholla supplies her with water...
然后用剩下的刺进一步加固防御
..and the severed spines further reinforce the defences.
这棵果实
This cholla bud...
可能是下一个牺牲品
..might be next.
但一次意外的碰触
But one accidental nudge...
它逃脱了
..and it escapes.
果实开始扎根发芽
The bud starts to put down roots.
在白喉林鼠的间接帮助下
So, the cholla, thanks to the pack rats,
圆柱掌的后代找到了新领地
finds new territory
并定居于此
and sets about claiming it.
很少有植物像仙人掌这样 从容地应对荒漠环境
Few plants deal with the problems of desert living better than cacti.
全球范围内共有将近2000种仙人掌
There are almost 2,000 different species of them.
它们遍布美国西部的沙漠
They're spread across the deserts of the American West,
从亚利桑那州 再到墨西哥 以及更遥远的荒漠
from Arizona, all the way to Mexico and beyond.
在南美洲安第斯山脉 被冰雪覆盖的连绵山峰
In South America, the ice-covered peaks of the Andes
形成一道阻隔水汽的屏障
act as a rain barrier...
山脉的西侧 因此成为了全世界最干旱的荒漠
..beyond which lies the world's driest desert -
阿塔卡马沙漠
the Atacama.
在荒漠环境中 偷水贼会采取各种不同的手段
In the desert world, water thieves can come in many forms
就连仙人掌刺毛的防御缝隙 都不会放过
to exploit even the smallest chink in a plant's defence.
有一种奇特的植物种子
One of the strangest travels within the gut
通过被小嘲鸫吞食 实现了旅行
of a fruit-eating mockingbird.
它是一种桑寄生科植物
These are the seeds of Tristerix,
仙钗寄生的种子
a kind of mistletoe.
它们的目标是这株仙人掌茎干中的水分
Their goal is the water inside this hedgehog cactus.
以仙人掌的刺为支撑
Using the spines as anchors,
种子开始发芽
the seeds start to germinate.
每个种子都会伸出一根触角
Each produces a long probe
用它来探寻仙人掌的表面
with which to try and locate the cactus' skin.
大多数种子 都会因为距离仙人掌表面太远
For most, that's a stretch too far,
无果而终
and they perish.
不过这颗种子 幸运地触到了仙人掌的表面
But for this one, the cactus' surface is within reach.
它用一个特殊的吸盘吸附在上面
It clamps onto it with a special sucker...
然后等待夜幕降临
..and then waits for darkness.
到了晚上 仙人掌会张开气孔呼吸
At night, the cactus opens its pores in order to respire.
排出氧气
Oxygen goes out,
吸入二氧化碳
carbon dioxide goes in,
仙钗寄生也趁机探入茎干内部
and so does Tristerix.
随即 它的组织就会在仙人掌的内部蔓延发展
Once within, its tissues spread throughout the body of the cactus,
借助其中的珍贵水源维持生命
sustained by the precious store of water that they find there.
到了第二年
Then, a year later,
它就会突破了仙人掌的表面
it breaks through the cactus' skin...
开出鲜艳的花朵
..and bursts into flower.
蜂鸟会来吸食花蜜
Hummingbirds come to drink their nectar
同时也为它们完成授粉
and pollinate them as they do so.
当这一生命循环接近尾声时
And, then, to complete the cycle,
仙钗寄生 会结出数百颗醒目的白色果实
Tristerix produces hundreds of white, eye-catching seeds,
等待鸟类再次把它们的种子
ready to be carried away by a bird
带到另一株仙人掌上
to invade another cactus.
这里是非洲南部的卡鲁沙漠
The Karoo Desert in southern Africa.
虽然它看起来很荒凉
And although it may look bare,
但这里的土地上 生活着种类丰富的植物
its rocky ground contains an unrivalled variety of plants that,
它们在储存水资源方面 各显神通
one way or another, store water in their tissues.
这些植物虽然分属不同的科 但人们通常把它们
They belong to many different families, but as a group,
称为多肉植物
they're known as succulents.
有些多肉植物又矮又小 与周围环境
Some are small and low and barely distinguishable
几乎融为一体
from their surroundings.
这种生石花属植物看起来像小石块
These look like little pebbles.
它们与周围环境极为相似
They resemble them so closely
就连那些急于偷水的动物们
that animals which might be only too glad to steal their water
都会忽略它们
just pass them by.
一旦出现降雨 它们就会吸收水分并迅速膨胀
When rain does fall, they absorb it and quickly expand.
不过这个过程并不会破坏伪装
But even this doesn't spoil their disguise.
它们只不过看起来像更大的小石块
They just look like larger pebbles.
它们也不是绿色的
Nor are they green.
这种多肉植物的顶面是透明的
The cells on their top surface are transparent
阳光可以透过顶面进入内部
and allow sunlight to pass through.
生石花属植物的叶绿素
Deep within and out of sight
就藏在茎的深处 不易察觉
are the green cells where photosynthesis occurs -
它们在这里进行光合作用 利用光照为植株制♥造♥能量
the process which uses this light to make food for the plant.
然而 当繁殖季节到来时
When the time comes to reproduce, however,
这种石头一样的植物就会放弃伪装
the stone plant abandons its disguise.
而现在 它开花了
And now, it blooms.
花朵每24小时会开放 闭合一次
The flowers open and close every 24 hours.
所以这种植物在几天时间内
So for a few dangerous days,
甘冒风险 吸引动物前来传粉
the plant advertises for pollinators
然后回归石块一般的平淡生活
before returning to life as a pebble.
有些荒漠植物会用另外一种方式
Some desert plants have developed a very different way
吸引传粉动物
of attracting pollinators.
这是一株毛犀角
This is a Stapelia.
或许在这片荒漠中 它的伪装最为奇特
It produces what is perhaps the desert's strangest disguise.
它利用茎干中的水促进花苞的生长
It uses water stored in its stems
等花苞长到网球大小就会绽放
to grow buds the size of tennis balls.
完全开放的毛犀角花 也被人们称为沙漠海星
The flower, once opened, is called a desert starfish.
大部分植物的花朵 都会展露出数以百万的
Instead of releasing millions of loose pollen grains
花粉颗粒
as most flowers do,
而沙漠海星却将花粉颗粒都包裹在5个微小囊袋中
the desert starfish produces them packed in five tiny sacks.
不过一旦策略成功
But if its strategy is successful,
那么一个囊袋就能结出数百颗种子
just one of them will produce hundreds of seeds...
能否结籽取决于骗局的效果
..and this depends on deception.
毛犀角的花朵长有绒毛
The flower appears to have hair...
表皮带有褶皱
..wrinkly skin...
而且散发出动物尸体般的臭味
..and it produces a stench like the carcass of a dead animal.
当一只腐肉苍蝇飞来探查时
And when a carrion fly investigates...
毛犀角会把一个花粉囊袋粘到它的口器上
..the flower tempts a tiny sack of pollen to its proboscis.
口器上罩着囊袋很难进食
It isn't easy to feed with such encumbered mouthparts.
但使出浑身解数 苍蝇依然无法摆脱它
But try as it might, the fly can't get rid of it.
当这只苍蝇飞去探查另一块伪装的腐肉时
And it's still there when the fly leaves to try and feed
囊袋依然存在
from another bogus carcass.
不过这一次 当它收紧口器钻进花芯时
This time, however, when its clamped-up proboscis
花粉囊袋脱落了
slots into the flower, the pollen sack is released.
既然授粉已经完成
With pollination complete,
毛犀角就不再需要苍蝇了...
the fly is no longer needed...
已经无妨了
..and just as well.
一些荒漠及其干旱 植物必须找到合适的方法
Some deserts can be so dry that plants must find techniques
在没有任何水源的情况下长♥期♥生存
of surviving for long periods without any water whatsoever.
其中一种方法是尽量减缓生长速度
One of them is to grow extremely slowly,
很少有植物比这棵植物生长得更慢了
and few plants grow more slowly than this one -
它就是三齿团香木
the creosote bush.
它生命中大部分时间都处于休眠状态
It is inactive for most of its life