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Tanzania's Lake Natron isn't exactly a pleasant place for a swim. The water is alkaline -- sometimes very alkaline.
坦桑尼亚的纳特龙湖并不是一个游泳的好地方。水是碱性的——有时候含量非常高。
Depending on the conditions, its pH can be higher than 10 -- that's a thousand times more basic than pure water.
根据情况不同，其pH值可以高于10，这是纯净水的1000倍。
Also, it is heated by volcanic geysers. The lake's temperature has been known to hit sixty degrees Celsius.
而且还有火山喷泉的加热。众所周知，这个湖的温度达到了60摄氏度。
Any animal corpses unfortunate enough to land in the water end up mummified in a coat of minerals,
任何不幸落入湖水中的动物尸体，最终都会被包裹上一层矿物，变成了木乃伊，
and touching it is seriously painful for humans. Because of that, it's hard to imagine that anything can live in this lake.
人类触摸到它会感受到异常的疼痛。因此，很难想象有什么能够在这个湖中生存。
And yet, Lake Natron is full of life. First, the lake has a distinctive, bright red color, and it gets that from a flourishing community of algae.
然而纳特龙湖里充满了生物。首先，这个湖的湖水是独特明亮的红色，这种颜色来自于茂盛的藻类群落。
The lake is home to a genus of brilliant red algae called Arthrospira, which loves salty, alkaline water.
湖中居住着一种明亮的红色藻类——节旋藻，它喜欢咸咸的碱性水。
But these algae are not alone. They're the basis for the lake's very own ecosystem.
但这些藻类并不孤单。它们是湖泊自身生态系统的基础。
Lake Natron, and other alkaline lakes across the region, are home to a genus of fish called Alcolapia,
纳特龙湖和其他穿过该区域的碱水湖中都居住着一种鱼——雀丽鱼，
which have evolved unique adaptations to withstand the toxic environment they call home.
它们进化出了独特的适应性，能够忍受被它们称为家的有毒环境。
For example, alkaline lakes are full of ammonia, which is toxic to many forms of life.
例如，碱水湖中充满了氨，这种气体对很多种类的生命都是有毒的。
Land animals can usually process ammonia by converting it to urea, which is less toxic, but this process takes up a lot of energy.
陆地动物通常可以通过将氨转化为尿素来处理它，尿素毒性较低，但这一过程要耗费大量精力。
And some saltwater fish have similar adaptations. The problem is, when it comes to freshwater fish,
一些咸水鱼有类似的适应力。问题是，对淡水鱼来说，
it doesn't take a lot of ammonia to be toxic-- just half a milligram in a liter of water can start to cause issues.
少量氨都会让它们中毒——一升水中只要有半毫克就会引起问题。
So Alcolapia have evolved an enzyme that lets them convert ammonia to urea without using too much energy.
所以雀丽鱼已经进化出了一种酶，让它们将氨转化成尿素且不需要耗费太多能量。
And that allows them to survive in waters that have been shown to kill other similar species of fish within an hour.
这让它们能够在这片能在一小时内杀死其他类似鱼种的水域中生存。
Alcolapia have also evolved a higher internal pH compared to most fishes.
和大部分鱼类相比，雀丽鱼也进化出了更高的体内pH值。
That means they don't need to spend as much energy protecting their internal pH from changing because of the environment they live in.
这意味着它们不需要那么多的能量来保护自己体内的pH值不受其所处环境的影响。
But as you may guess, there's a trade-off here. These fish are adapted to live in alkaline lakes, and only alkaline lakes.
但大家可能会猜，这样是有代价的。这些鱼适应生活在碱水湖，而且只生活在碱水湖中。
These fish have adapted to live in an incredibly specialized ecological niche -- a.k.a. their role in the greater ecosystem.
这些鱼已经适应了生活在一个令人难以置信的特殊生态位——即它们在更大的生态系统中的角色。
Because they live in a place that's so difficult for other organisms to tolerate, they can thrive without competition from other fish.
因为它们生活在其他生物体难以忍受的地方生活，所以它们可以在没有其他鱼类竞争的环境中茁壮成长。
But that also means that these fish can't survive anywhere but in Lake Natron and places like it.
但这也意味着，这些鱼只能生活在纳特龙湖和其他环境类似的地方。
Lake Natron is also the breeding grounds of the Lesser Flamingo. Despite their name, there's nothing inferior about these birds.
纳特龙湖也是小红鹳的繁殖区。除了名字，这些鸟也没什么差劲的。
Like Alcolapia, Lesser Flamingos are specially adapted to take advantage of everything Lake Natron has to offer.
和雀丽鱼一样，小红鹳特别善于利用纳特龙湖的一切资源。
These flamingos have tough skin on their legs to prevent burns from the caustic water.
这些红鹳的腿上有着有坚硬的皮肤，可以防止腐蚀性水的烫伤。
The high temperatures don't seem to bother them, either --
高温似乎也并没有困扰到它们，
they can submerge their heads in water that's so hot, it's almost boiling.
它们可以把头浸在热到几乎沸腾的水里。
How's that for a tacky lawn ornament? They have even been observed drinking boiling water from geysers with little to no ill effect,
做个俗气的草坪装饰怎么样？甚至有人观察到它们饮用火山泉中流出的沸水，且几乎没有任何不良影响，
although they prefer water at reasonable temperatures when they can find it. How they manage this is not clear.
虽然它们更喜欢常温水，如果能找得到的话。它们是如何做到这一点，还不得而知。
In a 2006 study, scientists found an unusual structure in the flamingo's head. And while they couldn't determine exactly what it did,
在一项2006年的研究中，科学家们发现，在红鹳的脑袋中，有一种不用寻常的结构。虽然他们不能确定它到底做了什么，
they did have some hypotheses, including that it could act as a heat exchanger of some kind.
但他们确实提出了一些假设，包括这种结构可能是某种换热器。
However, they found it more likely that the structure supports the bird's head as part of its peculiar upside-down style of feeding.
但他们发现，这种结构更有可能的支撑着它们的头部，是它独特的倒立进食方式的一部分。
Flamingos also prefer their water fresh -- but when it's not available, the lesser flamingo can adapt and overcome.
红鹳也喜欢淡水——但当没有淡水时，小红鹳能够适应并克服。
They can drink the salty, alkaline water of Lake Natron because of salt glands in their heads,
它们可以饮用纳特龙湖中咸咸的碱水，因为它们脑袋中的盐腺
which filter out the excess minerals through their nasal cavity and pass clean water to the rest of their body.
通过鼻腔过滤掉多余的矿物质，将洁净的水输送到身体的其他部位。
Just like Alcolapia, when they're in Lake Natron, the flamingos' favorite thing to eat is Arthrospira.
和雀丽鱼一样，当纳特龙湖时，红鹳最喜欢吃的食物就是节旋藻。
And as you might have heard, the brilliant pigments from the algae get passed to the birds' feathers --
大家可能听说过，海藻中鲜艳的色素传到了它们的羽毛上——
giving our favorite lawn decorations their pink color. These incredible adaptations mean that flamingos rule the roost at Lake Natron,
把我们最喜欢的草坪装饰品染成粉红色。这些惊人的适应力意味着红鹳统治着纳特龙湖和
and in all the other alkaline lakes that make up Africa's Great Rift Valley.
构成非洲大裂谷的所有其他碱性湖泊。
But also like Alcolapia, flamingos have evolved to take advantage of a specialized environment,
但和雀丽鱼一样，红鹳很擅长利用这种特殊的环境，
and that means that their habitat needs to stay stable in order to keep the species healthy.
这意味着它们的需要保持稳定，才能保持物种的健康。
Flamingos depend on these alkaline lakes to breed. They can't outcompete other birds anywhere else.
红鹳依靠这些碱性湖泊繁殖。它们在任何地方都无法胜过其他鸟类。
Unfortunately, soda ash mining, which extracts sodium carbonate from alkaline lakes like Lake Natron, is encroaching on their breeding grounds.
不幸的是，从碱水湖，如纳特龙湖，中提取碳酸钠的纯碱开采正在侵占它们的繁殖地。
Which means a balance must be struck between human activities and the needs of the bizarre,
这意味着必须在人类活动和那些已经适应
unique creatures that have adapted to live in alkaline lakes. Because really, where would we be without flamingos?
生活在碱水湖中的奇异、独特的生物之间取得平衡。因为说真的，如果没有红鹳，我们会在哪里？
And where would we at SciShow be without our patrons? Up to our knees in an alkaline lake? Not literally, but kinda metaphorically!
如果没有我们的赞助人，我们的节目又将会如何？跪在减水湖里？有点比喻的意思！
If you're interested in being one of the people that helps us make these videos from week to week, check out patreon.com/scishow.
如果你想成为我们赞助人帮助我们制作每周视频，点击patreon.com/scishow。
