巨大的長(zhǎng)頸蜥腳類恐龍能夠吃樹頂上的嫩枝,而其它的植食恐龍完美地適應(yīng)了利用較低處生長(zhǎng)的植物。
When you look at Stegosaurus and Camarasaurus, you'd be hard pressed to find two dinosaurs with such different feeding habits.
在觀察劍龍和圓頂龍時(shí),你會(huì)驚訝地發(fā)現(xiàn)這兩種恐龍的進(jìn)食習(xí)性迥異。
Camarasaurus feeds high in the trees, where as Stegosaurus was a low browser.
圓頂龍?jiān)跇涞母咛庍M(jìn)食,而劍龍則在一個(gè)低處進(jìn)食者。
Since both of these dinosaurs went extinct at the end of the Jurassic, then it's safe to suggest that all plants, from the tallest trees to the lowest shrubs,
因?yàn)檫@兩種恐龍都在侏羅紀(jì)末期走向滅絕,這就很容易推測(cè)所有植物,從最高的樹木到最低的灌叢,
were affected by some sort of environmental change and if the plants were changing, this would have a huge impact on the plant eaters who relied on them for life.
都受到某種環(huán)境變化的影響,而且如果植物在變化,就會(huì)對(duì)以它們?yōu)槭车闹彩痴咴斐删薮笥绊憽?/p>
The late Jurassic period also saw predators develop all around the globe, Allosaurus and Ceratosaurus were the deadliest.
晚侏羅紀(jì)時(shí)期也見(jiàn)證了掠食者在全球的發(fā)展,異特龍和角鼻龍是最致命的。
Ceratosaurus was more of a niche predator.
角鼻龍更是一種小生境的掠食者。
It certainly would have had to been specialized on a certain type of behavior with feeding.
它當(dāng)然必須要有某種專門的進(jìn)食行為。
It may have fed solely on Sauropods, it may have fished, it may have gone after smaller prey.
它可能只以蜥腳類恐龍為食,它也許以魚類為食,它可能攻擊更小的獵物。
Big animals like Allosaurus and Ceratosaurus are the first to suffer during a dramatic climate change.
像異特龍和角鼻龍這樣的大動(dòng)物在劇烈的氣候變化中最先受難。
Because of their sheer size, they require a certain amount of food and a certain amount of water.
因?yàn)樗鼈兊木薮篌w型,它們需要一定量的食物和一定量的水。
But just as dinosaurs were beginning their ascent, a massive explosion in deep space would start a countdown to their demise.
不過(guò)在恐龍開始漸漸繁盛之時(shí),深遠(yuǎn)的太空中一次巨大的爆炸開始了它們滅絕的倒計(jì)時(shí)。
Two giant asteroids collided.
兩顆巨大的小行星相撞了。
The larger of the two was called Baptistina.
兩顆中較大的那顆被稱作巴蒂斯緹娜。
We think it was probably on the order of about a 170 kilometers across.
我們認(rèn)為它的直徑大概有170千米。
And then, something very large slammed into it, we think about 170 million years ago.
后來(lái)有個(gè)很大的東西撞上了它,我們認(rèn)為是在一億七千萬(wàn)年前。
The size of the impactor isn't quite known, but we think it might be on the order of about 60 kilometers or so.
撞擊物的大小并不確定,但我們認(rèn)為大概是60千米(的直徑)。
And that completely pulverized we call the Baptistina parent body.
那完全粉碎了巴蒂斯緹娜母體。
The impact between these two celestial missiles caused Baptistina to break up, shooting fragments out of orbit and into the solar system.
這兩枚天體導(dǎo)彈的碰撞導(dǎo)致了巴蒂斯緹娜的解體,碎片從其軌道上射出進(jìn)入了太陽(yáng)系。
Most of these fragments ended up floating harmlessly in space, but a few headed toward a collision with earth.
這些碎片中的多數(shù)在太空中無(wú)害地漂浮著,不過(guò)有一些卻向著地球迎頭撞來(lái)。
This massive asteroid strike would ultimately wipe out the dinosaurs for good.
這次巨大的小行星撞擊最終會(huì)讓恐龍永遠(yuǎn)消失。
But strangely, this cataclysm from space was not the first massive disaster that the dinosaurs faced.
但奇怪的是,這來(lái)自太空的大災(zāi)難并非恐龍們面對(duì)的第一次大災(zāi)難。
100 million years earlier, the dinosaurs suffered another less complete extinction.
在此一億年前,恐龍?jiān)馐苓^(guò)另一次沒(méi)那么徹底的滅絕事件。
This first extinction came towards the end of the Jurassic period.
這一次滅絕事件在侏羅紀(jì)的末期到來(lái)。
It is estimated that 25% of all life forms were wiped out.
據(jù)估計(jì)所有物種的四分之一消失不見(jiàn)。
When the environment changed at the late Jurassic, it really caused problems for the bigger dinosaurs.
當(dāng)環(huán)境在晚侏羅紀(jì)時(shí)期發(fā)生變化時(shí),真的對(duì)較大的恐龍?jiān)斐闪寺闊?/p>
Allosaurus and Ceratosaurus could simply be victims of their inability to adapt to this new environment.
異特龍和角鼻龍可能就因?yàn)闊o(wú)法適應(yīng)新環(huán)境而成為犧牲品。
Today, it's still a mystery.
如今,這仍是個(gè)迷。
Some believe that they may have been the victims of their own success.
有些人相信它們可能是自己成功的犧牲品。
They seemed to have been driven to extinction by their own success.
它們好像是被自己的成功推向滅絕。
That sounds strange, but once you think about it, a successful dinosaur is one that produces descendants, and in the next time period,
那聽(tīng)起來(lái)很奇怪,不過(guò)要是仔細(xì)想想,一種成功的恐龍就是能產(chǎn)生后代的恐龍,而在接下來(lái)的時(shí)期,
the early Cretaceous, there are new Allosaurs and new Ceratosaurs in different parts of the world.
在早白堊紀(jì),在世界各地會(huì)有新的異特龍和新的角鼻龍。
More sophisticated descendants of each of these forms.
它們都是這些更為復(fù)雜的后代。
Things that were too sophisticated for the original Ceratosaurus and the original Allosaurus to compete against.
對(duì)原始的角鼻龍和原始的特異龍來(lái)說(shuō)它們太復(fù)雜的東西,以至于無(wú)法跟它們抗衡。
So as old fashion Ceratosaurus and old fashion Allosaurus themselves, they both disappeared.
所以老式的角鼻龍和異特龍自己就都消失不見(jiàn)了。
But in every major extinction, no matter how catastrophic, there are always some survivors.
不過(guò)每次大規(guī)模滅絕中,無(wú)論災(zāi)難性多大,總有一些幸存者。
And for those plants and animals that are able to adapt quickly enough, the world is theirs for the taking.
而對(duì)那些能夠很快地適應(yīng)的植物和動(dòng)物來(lái)說(shuō),世界就是它們的了。
It's easy to think that all dinosaurs lived and died at the same time, but that's not the case.
人們很容易認(rèn)為所有恐龍都在同一時(shí)期生活和消亡,但并非如此。
For instance, dinosaurs like Stegosaurus, Allosaurus, and Camarasaurus lived in the Jurassic Period and died out tens of millions of years before dinosaurs like Tyrannosaurus Rex showed up.
比如,生活在侏羅紀(jì)時(shí)期的恐龍,像劍龍、異特龍和圓頂龍,消失于像雷克斯暴龍這樣的恐龍出現(xiàn)數(shù)千萬(wàn)年前之前。
In fact, the time that separates those dinosaurs from T-Rex is longer than the amount of time that separates T-Rex from us.
其實(shí),那些恐龍和霸王龍間的時(shí)間間隔要比霸王龍和我們之間的間隔還要長(zhǎng)。