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Thanks to Brilliant for supporting this episode of SciShow.
感谢Brilliant对本期节目的支持。
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登录Brilliant.org/SciShow了解如何让你的STEM技能更上一层楼。
It's not easy to live in southern Africa's Namib Desert.
在非洲南部的纳米布沙漠生活并不容易。
It's one of the oldest and driest deserts in the world, and many of the plants and animals
这是世界上最古老、最干涸的沙漠之一，很多在此存活的植物和动物
that survive there have bizarre adaptations—and are only found in this desert.
都拥有怪异的适应性——且仅发现于这片沙漠。
One of these is the nara melon, which not only builds its own habitat in this harsh environment,
其中之一就是纳米比亚甜瓜，它不仅在这片恶劣环境中建立了自己的栖息地，
but also forms the base of a whole desert ecosystem. Deserts aren't known for being the coziest habitats, but even so, the Namib is extreme.
还构成了整个沙漠生态系统的基础。沙漠并不是最舒适的栖息地，但即使如此，纳米布沙漠也是一个极端。
It's been around for at least 55 million years, and it's been hyper-arid—or extremely dry—for the last five million or more.
它已经存在了至少5500万年，在过去的500多万年里，它一直处于极度干旱的状态。
It has an average annual rainfall of just ten centimeters, and sometimes years pass without any rain at all.
其年降雨量仅为10厘米，有时整年不下雨。
As a result, the sandy, dry soil gets easily blown around by the desert's strong winds,
因此，干燥的沙质土壤很容易被沙漠的强风吹走，
and it contains very little of the nutrients plants need to grow.
并且其中只含有很少的植物生长所需的营养。
Even so, there are plants here and the nara plant does so well that it grows a melon—a big, juicy fruit—in the desert!
即便如此，这里也有植物，并且nara植物做得非常好，还在沙漠中长出了甜瓜——一种又大又多汁的水果！
It's the only plant that grows fruit in the whole region, and to pull it off, it has to be extremely resourceful.
它是整片区域唯一一种结出果实的植物，要想把果实摘下来，必须极其聪明。
The nara plant creates its own stable habitat by building a mound of sand called a .hummock.
这种nara植物通过建造一种被称为小丘的沙堆来创造自己稳定的栖息地。
Initially, its seeds sprout on flat land, but as the plant grows, grains of sand and organic material get blown around it and cover up the bottom layer.
首先，它的种子在平地上发芽，但随着植物生长，沙粒和有机物质被吹到它周围，覆盖了底层。
That gives the plant a strong anchor in the sand, while the top layers keep photosynthesis going.
这为植物在沙地上提供了一个牢固的支撑点，同时表层的光合作用继续进行。
Over time, these hummocks can get up to ten meters high and 40 meters across! Scientists haven't studied nara hummocks in depth,
随着时间推移，小丘可以达到10米高，40米宽。科学家还没有对nara小丘进行深入研究，
but they can draw conclusions about them based on what they know about plant species in Chile's Atacama Desert that use a similar strategy.
但他们可以根据对智利阿塔卡马沙漠使用类似策略的植物种类的了解来得出结论。
The sand mounds they build capture organic matter blowing around in the wind as well as moisture from fog,
它们建造的沙丘可以捕捉风中的有机物以及雾气中的水分，
both of which help nourish the plants' growth in the sandy soil. So nara hummocks may play a similar role.
这两种物质帮助滋养砂土中植物的生长。所以nara小丘起到了类似的作用。
But the plant itself also has some incredible adaptations.
但植物本身也有一些难以置信的适应力。
For one, its roots go as much as 50 meters below the sand, where they can pull up groundwater.
首先，其根部能够深入沙地50米处，在那里它们可以抽取地下水。
Scientists also think it's possible that the plant harvests water from fog that rolls in from the coast.
科学家还认为，这种植物可能从海岸飘来的雾中获取水分。
Little cone-shaped spines all over the plant may help concentrate the fog into dew-like droplets,
遍布植物全身的锥形小刺可能帮助集中成露珠状的水滴，
which either get absorbed directly or run down grooves in the stem into the ground below.
它们要么被直接吸收，要么顺着茎上的凹槽流向地下。
Then, to avoid losing water in the super-dry air, the plant has just done away with leaves, which lose a lot of water to evaporation.
然后，为了避免在超级干燥的空气中损失水分，该植物舍弃了叶子，叶子会因蒸发而损失大量水分。
Instead, its green stems and spikes take care of its photosynthesis.
相反，其绿色的茎和刺负责光合作用。
With these tricks, scientists estimate that nara plants can live more than a century, including years without rain.
有了这些技巧，科学家估计nara植物可以存活一个多世纪，包括不下雨的年份。
But they don't just survive—they also make the desert more livable for a lot of other creatures.
但它们不仅活了下来，还让这片沙漠因为很多其他生物而变得更加宜居。
At least 26 vertebrate species depend on the plant for shade, water or food, including jackals, antelope, and mice.
至少有26种脊椎动物依靠它遮荫，提供饮水或食物，包括豺、羚羊和老鼠。
Beneath the plant, microbial communities also flourish in the nara's shade and provide the plant with vital nutrients in return.
在该植物下方，微生物群落也在nara的庇护下繁荣，作为回报，它们为这种植物提供关键营养素。
And to this day, the people who live in the region depend on these melons and seeds for food and income.
直到今天，这个地区的人们仍然依靠这些甜瓜和种子获得食物和收入。
Yet, as hardy as these melons are, they won't survive if you try to grow them yourself, and scientists don't quite know why.
但尽管这些甜瓜坚韧，但如果你想自己种植，是不会成功的，并且科学家也不知道其中原因。
Maybe they've just carved out a niche that's too specific to replicate.
或许它们只是另辟蹊径，太过特别而难以复制。
So for now, they remain a unique element of the Namib desert ecosystem!
所以到目前为止，它们仍是纳米布沙漠生态系统中的一个独特元素。
Thanks for watching this episode of SciShow! And thanks to Brilliant for sponsoring it.
感谢收看本期节目，感谢Brilliant对本节目的赞助。
If you want to freshen up your STEM skills or learn something new, Brilliant has dozens of courses you can explore.
如果你想更新你的STEM技能，或学习新知识，Brilliant 上有很多可以探索的课程。
For instance, they just added a brand-new course in math history,
例如，他们刚刚在数学历史栏目添加了一个全新课程，
which is designed to help you learn math alongside the people who discovered it.
专门帮助大家和发现者一起学习数学。
The courses are made by educators from institutions like MIT, Caltech, and Duke,
这些课程的制作人是来自MIT、加利福尼亚理工学院和杜克等大学的学者
and they're designed with interactive quizzes and guided problems.
他们还设计了互动测验和引导问题。
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成为会员，你可以浏览Brilliant的全部课程，
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前两百名注册Brilliant.org/SciShow的用户，还能获得年度订阅八折优惠。
