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Greetings, birdbrains! It's me, Dino!
大家好！是我，迪诺！
Jessi asked me to visit the Fort today to talk about my favorite subject in the whole wide world: dinosaurs!
杰西让我今天来参观沃斯堡，谈谈在全世界我最喜欢的话题：恐龙！
You've probably heard before that dinosaurs, the giant reptiles that walked the Earth millions of years ago, are extinct.
你之前可能听说过恐龙——几百万年前在地球上行走的巨型爬行动物，已经灭绝了。
That means they're not around anymore.
这意味着它们不存在了。
And it's true that most of the dinosaurs did go extinct. But not all of them.
的确，大多数恐龙都灭绝了，但不是所有。
65 million years ago, big changes were happening in the world.
6500万年前，世界发生了巨大变化。
Lots of volcanoes were erupting, and then a giant asteroid collided with Earth, in a huge explosion!
许多火山喷发，接着一颗巨大的小行星与地球相撞，产生了巨大的爆炸！
For a long time after that, the world was very dark, and then very cold, and then very hot.
在那之后的很长一段时间里，世界非常黑暗，然后变冷又变热。
With no sunlight, a lot of the plants died,
没有阳光，很多植物都死了，
so the dinosaurs that ate plants didn't have enough to eat, so many of them died, too.
所以以植物为食的恐龙没有了足够的食物，很多也死了。
That meant the dinosaurs that ate other dinosaurs didn't have enough food either, and a lot of them went extinct.
这意味着以其他恐龙为食的恐龙也没有了足够的食物，于是很多恐龙都灭绝了。
So, it was a really hard time to be a dinosaur!
所以，这是恐龙的艰难时期！
But some dinosaurs were clever and talented enough to tough it out.
但有些恐龙聪明又有天赋，挺过了难关。
Because, their bodies had just the right adaptations,
因为它们的身体有正确的适应能力，
certain traits that helped them survive these big changes.
某些特质帮助它们挺过了这些巨大变化。
The dinosaurs that survived had dinosaur babies,
幸存下来的恐龙生了恐龙宝宝，
and soon their babies had their own little babies, all the way down the family tree.
很快，它们的孩子就有了自己的孩子，一直发展形成了一个家族树。
And the animals that came from them are still living here on Earth! We call them … birds!
而来自它们的动物仍然生活在地球上！我们称它们为鸟类！
That means birds like me, Dino, are descendants of dinosaurs,
这意味着像我迪诺这样的鸟类是恐龙的后代，
and dinosaurs are my ancestors, like my great-great-great-greatgreatgreatgreat-grandparents!
恐龙是我的祖先，是我的祖祖祖祖祖祖父母！
I'm part of the dinosaur family tree!
我是恐龙家族的一员！
And since birds are part of the dinosaur family,
既然鸟类是恐龙家族的一部分，
I'm not just a descendant of a dinosaur… I am one! So the dinosaurs… live!
那么我不只是恐龙的后代，我也是恐龙！所以恐龙…还活着！
Now, how do we know that birds are related to dinosaurs?
我们怎么知道鸟类和恐龙有关呢？
Well! We have lots of clues, specifically from theropods,
嗯！我们有很多线索，特别是来自兽脚亚目恐龙的线索，
a group of two-legged dinosaurs that also included velociraptors and Tyrannosaurus rex!
兽脚亚目恐龙是一群两条腿的恐龙，包括迅猛龙和雷克斯霸王龙！
Hundreds of millions of years ago, way before the earliest birds appeared,
数亿年前，在最早的鸟类出现之前，
dinosaurs were developing lots of birdlike adaptations.
恐龙进化出了许多类似鸟类的适应能力。
Theropod dinosaurs especially, started to have a lot of birdlike traits that would later help birds take to the skies!
尤其是兽脚亚目恐龙开始有了很多类似鸟类的特征，这些特征后来帮助鸟类飞上了天空！
Like feathers! Lots of dinosaurs, even dinosaurs that didn't become birds, had feathers.
比如羽毛！很多恐龙，甚至没有变成鸟类的恐龙，都有羽毛。
Some of these feathers were more like little hairs, which probably helped dinosaurs keep warm.
其中一些羽毛更像小毛，这可能有助于恐龙保暖。
But some types of theropods wound up with bigger, fancier feathers, and even wings.
但有些兽脚亚目恐龙的羽毛更大、更华丽，甚至还有翅膀。
Before there were birds, fancy feathers might have been used to keep these dinosaurs and their eggs safe and warm,
在鸟类出现之前，奇特的羽毛可能用来保护恐龙自身与恐龙蛋的安全和温暖，
or to communicate with other dinosaurs.
或者用于和其他恐龙的交流。
But even though bigger theropods, like some kinds of tyrannosaurs, had feathers,
但即使体型较大的兽脚亚目恐龙，比如某些暴龙，也有羽毛，
they couldn't just flap their arms and fly around.
但它们不能挥动臂膀到处飞。
To really be able to get off the ground, you need wide, powerful wings, and a small body.
为了能够真正离开地面，你需要有宽阔有力的翅膀和一个小身体。
While lots of types of dinosaurs were becoming gigantic,
当许多种类的恐龙变得体型巨大时，
some theropods, including those that eventually gave rise to birds, were getting smaller.
一些兽脚亚目恐龙，包括那些最终进化成鸟类的兽脚亚目恐龙的体型变得越来越小。
So lots of dinosaurs already looked and moved a lot like birds.
所以很多恐龙的外形和运动方式已经很像鸟类了。
And some of the theropod dinosaurs were becoming more like birds all the time!
而且一些兽脚亚目恐龙正变得越来越像鸟类！
Getting smaller, growing wings, and developing beaks instead of teeth.
它们变得更小，长出翅膀，进化出喙而不是牙齿。
Over millions of years, all the pieces of the bird puzzle were coming together, one by one.
经过数百万年，所有的鸟类拼图碎片一个接一个地聚集起来。
By about 150 million years ago, the earliest dino-birds were in the air.
大约在1.5亿年前，最早的恐龙与鸟的复合体出现在空中。
Some of them could fly, but looked very different from the birds we know today.
它们有些会飞，但是看起来和我们今天知道的鸟类非常不同。
And some didn't fly, but had a lot in common with today's birds!
还有一些不能飞，但与今天的鸟类有很多共同之处！
Now, millions of years later, when that asteroid hit Earth, and the volcanoes started to erupte,
数百万年后，当小行星撞击地球、火山开始喷发时，
and everything started changing, some dinosaurs had a hard time surviving.
一切都开始变化，一些恐龙很难生存。
A lot of the big ones, like T-rex, were so big, they had trouble finding enough food to eat.
很多大型恐龙，比如霸王龙体型太大了，找不到充足的食物吃。
But the most birdlike groups of theropods were very small, only about 1 kilogram, or as heavy as a pineapple.
但是最像鸟的兽脚亚目恐龙体型非常小，只有1公斤重，或者像菠萝那么重。
That meant it was easier for them to survive on less food and to find places to live.
这意味着它们更容易靠较少的食物生存，更容易找到生活的地方。
And because they were so small, these early birds were also able to use their wings to take flight!
而且因为它们体型非常小，这些早期鸟类也能够利用它们的翅膀飞翔！
Not only did some of these flying dinosaurs survive … they really took off!
这些会飞的恐龙不仅存活了下来，而且还飞起来了！
We have more than 10,000 types of birds around today!
我们现在有一万多种鸟类！
So the next time you see one of us feathered friends flying around,
所以下次当你看到一个有羽毛的朋友飞来飞去时，
you'll be able to point to it and say, "Hey, look! A dinosaur!"
你可以指着它说，“嘿，看！一只恐龙！”
Thanks for joining me, birdbrains!
感谢您的收看！
Do you have questions about birds, or dinosaurs, or anything at all?
你对鸟类或恐龙或其他有什么问题吗？
Ask a grownup to help you leave a comment below,
找个大人帮忙在下方留言，
or send us an email to kids@scishow.com. See you next time!
或发邮件至kids@scishow.com.我们下期见！
