The Surprising Species That Everything Else Depends On | IN OUR NATURE (1) Die überraschende Spezies, von der alles andere abhängt | IN UNSERER NATUR (1) La sorprendente especie de la que depende todo lo demás | EN NUESTRA NATURALEZA (1) Les espèces surprenantes dont tout le reste dépend DANS NOTRE NATURE (1) すべてが依存する意外な種｜私たちの自然 (1) 다른 모든 것이 의존하는 놀라운 종들 | 우리 자연에서 (1) Stebinančios rūšys, nuo kurių priklauso visa kita | Mūsų gamtoje (1) De verrassende soort waar al het andere van afhangt IN ONZE NATUUR (1) Zaskakujące gatunki, od których zależy wszystko inne | W NASZEJ NATURZE (1) As espécies surpreendentes de que tudo o resto depende | NA NOSSA NATUREZA (1) Удивительные виды, от которых зависит все остальное | В НАШЕЙ ПРИРОДЕ (1) Doğamızdaki Her Şeyin Bağlı Olduğu Şaşırtıcı Türler (1) Дивовижні види, від яких залежить все інше | У НАШІЙ ПРИРОДІ (1) 其他一切都依赖的令人惊讶的物种|我们的本性 (1) 其他一切都依賴的令人驚訝的物種|我們的本性 (1)

This is a story about lions, and giraffes, and a microscopic little virus. It's also a story

about grass, and fire, and a bunch of these funny looking guys and what all of that has

to do with bombs, extermination and restoring ancient traditions and extinct ecosystems.

There's one big idea that ties all of these together, that even in a place overflowing Es gibt eine große Idee, die all dies miteinander verbindet, nämlich dass selbst an einem Ort, der überfüllt ist これらすべてを結びつけるひとつの大きな考え方がある。

with life, there's one species that keeps the whole thing from crumbling down. And what 生命には、全体が崩れないようにするための種がある。

happens if we take an ecosystem that's fallen apart and we add that one key species back. passiert, wenn wir ein Ökosystem, das aus den Fugen geraten ist, mit einer Schlüsselart wiederherstellen. 崩壊した生態系に1つの重要な種を戻すとどうなるか。

Can we fix it? Trace, and Emily and myself, we're going to be bringing you a series of トレース、エミリー、そして私の3人でこのシリーズをお届けする。

stories, featuring some incredible storytellers, some really passionate scientists and a bunch 素晴らしい語り手たち、情熱的な科学者たち、そして多くの人々が登場する。

of people who just really care about wild places. We're exploring the rules of life 野生の場所を本当に大切に思っている人たちの集まり。 私たちは生命のルールを探求している。

that connect ecosystems, even half a world apart like Africa's Serengeti and a Native アフリカのセレンゲティのように、たとえ地球の裏側であっても、生態系はつながっている。

American Tribal Community in South Dakota. And while we're at it, we're going to find サウスダコタ州のアメリカ人部族コミュニティ。

out a little more about our place in all of this. Hey, hi, Trace Dominguez Emily Grasley. トレース・ドミンゲス・エミリー・グラスリーです。

It is so good to see your faces. I am really excited to tell people about this thing, this 皆さんの顔を見るのがとてもうれしいです。

thing we've been working on, I don't know what to call it. Well, I guess it all started 僕らが取り組んできたこと、なんて言うんだろう。 まあ、すべてはここから始まったんだと思う。

with an idea that there's a different way to tell stories about nature that maybe we've 自然について語るには、これまでとは違った方法があるはずだ。

been doing it all wrong. A way to look at the, を見る方法だ、

Yeah, I feel like when I'm looking at a science story, I tend to get like hyper focused and

you get sort of a narrow lens on what you're looking at, and you have a tendency to miss 視野が狭くなり、見過ごしがちになる。

the other stuff that's around you, あなたの周りにある他のもの、

Because really everything in nature is connected to so many other bits in nature. And often in ways that なぜなら、自然界に存在するすべてのものは、自然界に存在する他の多くの断片とつながっているからだ。 そして、しばしば、以下のような形で。

you don't even expect if you're not looking, That's what this is all about. And what we're それこそが私たちが目指すものだ。

going to do is show you how these big ideas, The rules of life

Are all connected and how we fit into that. I figured we'd start in the Serengeti. It's sind alle miteinander verbunden und wie wir dazugehören. Ich dachte, wir fangen in der Serengeti an. Es ist まずはセレンゲティから始めよう。

an amazing place, but to tell all the stories that happen in that place, I feel like you 素晴らしい場所だが、その場所で起こるすべての物語を語るには、私はあなたが必要だと感じている。

need to understand why it even exists in the first place. Wow. Wow. Yeah. That is Jahawi そもそも、なぜそれが存在するのかを理解する必要がある。 ワオ、ワオ、そうだ、これがジャハウィだ

Bertolli. He is this photographer and filmmaker from Kenya. I met up with him out in the Serengeti ケニア出身の写真家で映像作家のベルトッリだ。 セレンゲティで彼に会った。

because he's been going out there his whole life. なぜなら、彼はずっと外に出ていたからだ。

I mean, just look at the scope of this. Absolutely incredible. When you think of big drama in a place like このような場所で大きなドラマがあるなんて、本当に信じられない。

the African Serengeti, what's the first thing that pops into your head. Dung beetles, cheetahs. アフリカのセレンゲティでまず頭に浮かぶのは何だろう。 糞虫、チーター。

Those are not the answers I'm looking for. The answer is these guys. No, seriously, you 私が求めているのは、そんな答えじゃない。 答えは、この人たちだ。 いや、マジで、君だ

are looking at the most important event on the entire Serengeti ecosystem. セレンゲティの生態系全体にとって最も重要な出来事である。

It's eating grass, Joe. I don't, I don't. Okay. Okay. 草を食べてるんだよ、ジョー。

I get it will, they are kind of goofy. They got that whole goatee thing going on. They あごひげを生やしている。

have that funny rear end kind of looks like somebody forgot to finish them, but they might でも、もしかしたら、そのようなことがあるかもしれない。

be the reason that the African Serengeti even exists. アフリカのセレンゲティが存在する理由である。

Um, excuse me. I learned from the documentary Lion King that that is not the case. 私は『ライオン・キング』のドキュメンタリーで、そうではないことを学んだ。

I don't know how to tell you this, but, um, your childhood might've been a lie. Hey, have どう言えばいいかわからないけど、君の子供時代は嘘だったかもしれないよ。 ねえ、ある？

you guys ever seen this pyramid thing? It's kind of a zoomed out way of looking at how このピラミッド、見たことある？

ecosystems are organized. So down at the bottom, you've got all the stuff that does photosynthesis, 生態系は組織化されており、一番下には光合成を行うすべてのものがある、

the plants and everything like that. And here in the middle, you've got the stuff that the そして、この真ん中にあるのは

plants and at the top, you've got the stuff that eats the stuff that eats the plants,

Everything at the top that kind of regulates everything underneath it. Right? トップにあるものすべてが、その下にあるものすべてを制御しているんだ、そうだろ？

That is what I thought, but that is not how the Serengeti works. One thing you got to 私もそう思っていたが、セレンゲティはそうではない。

understand about wildebeests, okay, is just how many of them there are, I mean wildebeests everywhere. つまり、どこにでもいるのだ。

Joe, you went to Africa like one time. Okay. Yeah. Joe, du warst ein Mal in Afrika. Okay. Ja. ジョー、一度だけアフリカに行ったことがあるよね。 うん。

Jahawi helped. So not far from us, it's a big herd of wildebeest.

Is this all of them? Like all of them, Can you imagine? Not even a tiny bit. これで全部ですか？ 想像できますか？

Every direction that we look is wildebeests, as far as we can see.

Just in this little area, how many do you think there are.

Easily at thousands without turning my head. And then in the distance, we see this massive group そして遠くに、この巨大な集団が見える。

of zebra, several thousand zebra, which migrate with them. It looks like the horizon is made 数千頭のシマウマが一緒に移動している。 水平線が作られているように見える。

of tiny black and white shapes, thousands and thousands. I mean, it's one of those things.

It's just, you can just keep counting. You took all of the zebras and the giraffes シマウマもキリンも全部連れて行ったんだから。

and the antelope and the gazelle. If you took the next 12, most abundant herbivores on the 次の12種は、草食動物の中で最も数が多い。

Serengeti, wildebeests would outweigh all of them.

How is that possible? That's the big question. That's what scientists wanted to know. How 科学者たちはそれを知りたかったのだ。

can this place support so many of those funny looking wildebeests. Yeah. I don't understand. ああ、理解できない。 kan deze plek zoveel van die grappig uitziende gnoes ondersteunen. Ja. Ik begrijp het niet.

Well, I'm going to tell you, but to do that, we have to go back in time to when the Serengeti

was not like this to the 1950s. So back then nobody really studied the Serengeti and scientists

were like, you know, maybe the first thing we should do is just count everything. So だから、まず最初にやるべきことは、すべてを数えることなんだ。

they started with the wildebeests and the first year they counted like 250,000 wildebeests.

Then a few years go by and all of a sudden there's 400,000 wildebeests. I would say that's

a lot of new gnus. Emily, I love it. Gnu news, cause with エミリー、私はそれが大好きだ。

the G love it. Right. And then just a few years after that there's 700,000. Fast forward そして、その数年後には70万人になった。

a few more years, there's 1.4 million wildebeests. This is totally weird because based on everything あと数年すれば、140万頭のヌーが生息することになる。 これはまったく奇妙なことだ。

scientists knew up to this point, like large animal populations just don't do this. I mean 科学者たちはこの時点まで、大きな動物の個体群ではこのようなことは起こらないと知っていた。

sure. Like fish, rabbits, plankton, they have these huge rapid population explosions, but

giant mammalian herbivores, that just doesn't happen. And actually people started to get

worried, like maybe this is too many wildebeests. Sure. The Serengeti is pretty great, but maybe

it can't support all of them, but then they realized something. You weren't looking at

a population explosion they're were looking at a rebound. 人口が爆発的に増えれば、その反動がくるだろう。

Okay. But rebounding from what? Like over-hunting or like an ice-age extinction? How many viruses しかし、乱獲や氷河期の絶滅から立ち直るにはどうしたらいいのだろう。 どれだけのウイルスがいるのだろう。

have humans completely eradicated from the earth? Like in the history of ever? The answer 人類は地球上から完全に根絶やしにされたのだろうか？ これまでの歴史の中で、そうであっただろうか？

is just two, smallpox and a virus called rinderpest. Rinderpest was this cattle virus. That's like

thousands of years caused civilization level plagues and famines that infecting and killing 何千年もの間、文明レベルの疫病や飢饉を引き起こしてきた。

cattle and other ruminants. Thanks to massive vaccination efforts, the last reported case

was in 2001, but if you go back a hundred years before that, rinderpest was accidentally

introduced to Africa in the 1890s. And by the 1900s it killed like 90% of the wild wildebeest

and Buffalo in east Africa, early to passed the vaccine came the 1950s. And by the 1960s, そして1960年代には、東アフリカのバッファローが早くからワクチンを接種するようになった、

this virus was basically under control. This virus had been keeping wildebeest populations

down for like 70 years. And it wasn't just wildebeests. When they came back, scientists 野牛だけでなく、彼らが戻ってきたとき、科学者たちはこう言った。

started seeing a whole bunch of other changes in the ecosystem, changes that were pretty

surprising. Are there lions in this part? you know I'm going to want to see some lions. この地域にライオンはいますか？

Okay. Yes, there are lions in this park, but we're not done with grass yet. Okay. So one wildebeest doesn't eat that much, but a million この公園にはライオンがいる。

and a half wildebeest eat more than 9 million pounds of grass every single day.

And that's enough to shape a whole ecosystem. You know, wildebeests are quite picky eaters

and they basically like short grass, you know? So like now here on the short grass plains,

this is perfect for them, but they also like new shoots. That's like, it's like a child,

like children are aren't even that picky. Zebra, they're not so picky. So they tend

to actually come through first and clear, clear the way. And then, then the wildebeests

can get what they want. Wow, exactly. Cooperative eating.

So if you eliminate this virus, you get more wildebeests, more hungry wildebeests means

less grass. And because more grass is being eaten, that means less fuel for fires and

less wildfire means that more young trees get to grow and more trees growing means more

food for giraffes and elephants and birds too. And of course more wildebeests means

more food for predators. Hey, now we're at the lion part, right?

Yes. Lion numbers went up and so did hyenas and other predators too. They are the Keystone

species of this ecosystem. Ding, ding, ding. He said the name of the

episode in the episode! It's a $6 million word. It's incredible to think of enormous groups

like this, just moving across this land, eating and pooping.

I mean, you can imagine the effect on the ecosystem. I've seen the migration and then

I've been lucky enough to see it quite a few times, but I can't help, but be blown away

every time by the sheer size, the number there's very few places left that can support these

kinds of herds. People had always just assumed that a Keystone

species had to be a predator, but here you've got these funny plant eaters, keeping an entire

ecosystem from collapsing. And, in fact, they're making it better. And today this million and

a half wildebeests are the largest herd of plant eating mammals on earth.

The population it's not still growing. I mean that wouldn't be sustainable, right?

No. I mean, you can't have wildebeests growing and like slowly taking over the universe,

they remain remarkably stable. That's the next mystery the scientist had to solve. I

mean, why? Oh, Trace. There are definitely lots of lions in this part. I was going to

say, we're at the top of the pyramid. We're getting to the lions. We're getting predators,

its going to be great. Oh and hyenas too. Okay. So a lot of stuff

gets eaten in the Serengeti by those guys at the top of the pyramid, the predators.

But some animals get eaten more than others. Let's say you're something small, like an

Impala. Well, chances are, you're going to die at the hands of something with fang, claws. Impala. De kans is groot dat je sterft door toedoen van iets met hoektanden, klauwen. Імпала. Швидше за все, ви загинете від рук чогось з іклами, кігтями.

The pokey parts. У найдрібніших деталях.

They have what scientists call a high prediction rate. But if you're something big, like an

elephant or a giraffe, not a lot is going to mess with you. Ob Elefant oder Giraffe, es gibt nicht viele, die sich mit dir anlegen.

All right. All that makes sense. But where exactly are wildebeests then cause they're

big, but they're not elephant. Okay. The answer that

Scientists looked at, something that Emily knows a thing or two about bones, dead bones.

Oh yeah. Well actually bone marrow to be more specific

- sick. So here's the other thing you got to know about wildebeests. They move a lot

in the rainy season. The wildebeest are down in these grassy Plains where there's plenty 雨季になると、ヌーたちは草原に降りてくる。

to eat. But as the dry season begins, the, see a wildebeest moves north this thousand

kilometer cycle repeats itself every year. It's one of the greatest animal migrations

on Earth. So, you know, when, when a lot of people think

about the migration, they, they think wildebeests cause they call it the Great Wildebeest Migration. But in

reality, there's a lot of other animals that actually go along parts of the migration.

I mean, you've got Thompson gazelle, you've got a lot of zebra. What's the, what's the,

the advantage of, of them traveling with the migration. If we were zebra and things, it

is a part getting to the best grazing. And then you've got safety and numbers and lots