Like, there’s only a certain amount of land that we can build on,

像是我們就只有這麼多的土地可以蓋房子，

there’s only so much gold that we can mine... and there’s always the possibility of a bacon shortage.

只有這麼多的黃金可以讓我們挖...而培根也常有會缺貨的可能。

And for some scientists, there’s another commodity that’s in increasingly short supply.

但對有些科學家而言，有另外一種物品的數量正在快速減少。

Dinosaurs.

就是恐龍

Over the last couple of centuries, we’ve found thousands of dinosaur bones. But only a limited number of species ever existed, right?

過去幾個世紀中，我們找到了數以千計的恐龍骨骸，也只發現了幾種曾存在過的物種，對吧?

So some paleontologists have been wondering how many species of dinosaurs are actually left for us to discover

所以有些古生物學者開始思考到我們到底還可以發現多少新的物種

and how many fossils of them are out there?

和還有多少化石還存在著?

Might sound like a funny thing for scientists to ponder, but it’s really an extension of a larger question that they’ve been wrestling with

科學家為這問題煩惱聽起來或許有點好笑，但這其實延伸到一個讓科學一直困擾的大問題。

which is: How many different kinds of dinosaurs were there in the first place?

那就是，最一開始時有幾種恐龍物種?

Scientists who study living organisms deal with these questions all the time

生物學家也常面臨到這一類的問題

like, how many different types of plants and animals are living in this forest glade? Or how many

像是，有多少種的植物和動物住在紅樹林裡?

Or how many microbes are in this petridish?

或是在這培養皿裡有多少的微生物?

Since they can’t possibly count every single organism, they just count a small sample.

因為他們沒辦法一個一個數，所以他們只能先計算一個小樣本的微生物數量

Then, they use statistics and probabilities to come up with a mathematical model of what that whole population might look like.

之後再利用統計與機率，建構可以算出總體數量的數學模型

And in 2006, a team of biologists and statisticians used these methods to estimate Earth’s population of extinct dinosaurs.

在2006年，一群的生物學家和統計學家用這種方式概算出了地球上已滅絕恐龍的數量。

Specifically, they wanted to figure out how many types of dinosaurs there once were,

更重要的是，他們想找出地球上出現過的恐龍種類，

as well as how long it would take us to find fossils of each.

還有計算出找到這些化石需要多少的時間。

Scientists usually count dinosaurs by genus

科學家通常以「屬」來分類恐龍

that’s the taxonomic rank just above “species” because nine times out of ten, there’s only one species of dinosaur per genus.

這是「種」的上一個層級，因為十個裡有九個，一個「屬」的恐龍下面只會有一「種」恐龍

So the team started cataloging how many dinosaur genera had already been discovered.

所以有個團隊開始分類有哪幾個屬性的恐龍已經被發現了

Then they focused on how many of those genera were really common, and how many were really rare.

之後他們開始專注找出哪些屬性的恐龍比較常見，哪一些有是比較稀有的

In many cases, for example, a dinosaur genus might consist of just one known specimen,

在許多情況下，譬如說，一個恐龍的屬性可能就只有一個已知的樣本。

like the cute and creepy Segisaurus, which used to scamper around what is now Arizona.

像是過去在現今的亞利桑那地區奔跑，可愛又有點怪的 Segisaurus(恐龍物種)

But other genera were really common,

但其他屬的恐龍就特別常見

like, you can hardly swing a pick-axe in parts of America’s Northern Plains without hitting a fossil of Edmontosaurus.

如果你在美國北部平原拿鏟子東挖西挖的話，你很難不找到一個 Edmontosaurus 的化石

So, based on the abundance, or scarcity, of known organisms, scientists estimate the diversity of unknown ones as well.

所以根據已知生物的數量多寡，科學家可以估計出未知生物的多樣性。

Or at least, they try to.

或是說他們正試著這麼做

And the results so far suggest that while there are a lot of dinosaurs still out there for us to find,

而目前的結果顯示，雖然還有非常多的恐龍等著我們去發掘

we may have less than 200 years of good dinosaur hunting left.

但我們可能只剩不到兩百年的時間可以找到新物種的恐龍

As of 2006, the study concluded, we had discovered just 29 percent of the 1,850 dinosaur genera they think are out there, waiting to be found.

研究指出在2006時，我們已經發掘了1850種他們認為存在的恐龍屬性裡的29%了。

So, how soon until we find the very last known genus of dinosaur?

所以我們多快會找到最後一個物種的恐龍呢?

Well, because of better techniques being used in paleontology, we’re discovering new dinosaurs faster than ever before.

由於在古生物學上有更新的科技可以運用，我們現在發掘恐龍的速度比過去快上許多。

The very first dinosaur fossil was identified in 1824. For the next hundred and fifty years,

第一個恐龍化石是在1824年所發掘的。在接下來的一百五十年裡，

paleontologists only discovered an average of one new genus of dinosaur every year.

古生物學家一年平均只發現一種屬性的恐龍。

But now, we’re racking up an average of 15 new genera every year.

但現在我們平均一年就可以找到15新屬性的恐龍。

And as a result, according to scientists’ calculations, somewhere between the years 2037 and 2056,

根據科學家的計算，結果就是，在大約2037到2056年之間，

we’ll have found 50% of the dinosaur genera that ever existed.

我們將會找到50%存在過的恐龍屬性。

You might think of this as “peak dinosaur”. At that point, there would be more known dinosaurs than unknown ones.

你可以把這想成是一個「恐龍頂點」。在這頂點時，我們已知的恐龍數量將會超過未知的。

After “peak dinosaur,” there will be fewer genera left to discover, and the remaining ones will probably be scarcer.

過了「恐龍頂點」後，可以發掘的恐龍屬性將會變更少，而剩下的恐龍屬性也將會更稀有。

So the number of finds per year will start to decline.

所以每年可以發掘的屬性將開始下降。

But for a while, we’ll still be finding them often enough to keep dinosaur-hunters busy.

但在那之前，恐龍的數量還是可以讓恐龍考古學家有得忙。

Between 2069 and 2102, according to these projections, we’ll have found 75% of the dinosaur genera.

根據這些計畫，在2069和2102之間，我們將會發掘75%的恐龍屬性。

By the mid-22nd century, 90%.

在22世間中將會到90%。

And by the year 2200, there will be only a few genera left, and they’ll be harder to find than ever.

而到了2200年時，未發掘的恐龍屬性將所剩不多，也會變比以前難找許多。

At that point, even though there will probably still be some surprise discoveries of new dinosaurs every so often, those finds will be extremely rare.

在那時，或許還會意外發現新種的恐龍，但這樣的事將會變得很少見。

Basically, the golden age of dinosaur discovery will be behind us.

基本上，發掘恐龍的黃金時代將會在我們往後的日子裡。

However, these are just statistical estimates. It’s impossible to know when you’ve ever found the last of anything.

但話說回來，這只是統計上的預測，要知道和麼時候會找到最後一種東西是不太可能的事。

Plus, this timeline also only applies to dinosaurs, those reptilian land-dwelling diapsids

再加上，這個時刻表其實只運用在恐龍上...那些雙孔亞綱的陸棲爬蟲類。

it doesn’t include all the other ancient forms of life: pterosaurs, mosasaurs, plesiosaurs,

這還不包含其他的古生物，像翼手龍、滄龍、蛇頸龍、

fish, mammals, invertebrates, and plants!

魚類、哺乳類、無脊椎動物還有植物!

So there will still be plenty of fossils for us to find, for a very long time.

所以還是有非常多的化石讓我們可以找很久。

And don’t forget, we’ll still have the dinosaurs’ relatives,birds, to keep us company.

還有別忘了，我們還有恐龍的親戚，鳥類，可以陪伴我們。

Thanks for watching this episode of SciShow, especially to all of our Subbable subscribers.

謝謝你收看這集的 SciShow，特別是那些訂閱我們的觀眾

If you want to support us, you can go to subbable.com/scishow to learn more.

如果你想要支持我們，可以到 subbable.com/scishow 取得更多的資訊

And don’t forget to go to YouTube.com/scishow and subscribe!

還有不要忘記到 YouTube.com/scishow 和訂閱我們!