For most females of the Cretaceous, finding a mate who's stronger, more cleverer,
对于白垩纪的大多雌性来说，寻找一个更健壮，更聪明
and had more advanced killing tools than the next male is crucial. But that's not all.
比别的雄性拥有更加先进杀人武器的配偶至关重要。但还不仅如此。
For a T. Rex male, surviving to adulthood means he's probably had some good parenting himself.
对于雄性霸王龙来说，活到成年意味着他受到了父母精心的哺育。
And it's likely he's also developed some strong hunting skills...
而且很有可能具备强大的捕食技巧，
and probably even learned to duck when Quetzalcoatlus swooped down and tried to steal him as a chick.
甚至在披羽蛇翼龙俯冲直下偷幼崽的时候他还学会了躲避。
In other words, you don't make it this far without some good genes to pass down.
换句话说，如果没有优秀的基因的传承是不可能活这么长时间的。
But evolution isn't just about mating.
但是进化并不只有交配。
It's also about ensuring those valuable eggs actually hatch and grow up.
还要保证这些宝贵的卵能够孵化并长大。
The prehistoric world of the Cretaceous Period.
这里是白垩纪时期的史前世界。
Here roam creatures from the outrageously large...to the incredibly terrifying...and the truly bizarre.
这里栖息的生物大到顶天立地，恐怖到令人难以置信，再到稀奇古怪。
But every dinosaur, no matter how radical, is hatched from an egg.
但所有恐龙，无论多么激进，都是蛋孵化来的。
And like the well-engineered bodies they will eventually grow into,
如同它们将要长成的精密设计的身躯一样，
evolution has created some of the most advanced eggs history has ever seen.
进化也创造出了史上最高级的卵。
An egg is like a space capsule.
卵就像一间太空舱。
Everything that the embryo is gonna need is pretty much in there.
胚胎发育所需的一切差不多都在其中。
And evolution developed something else.
进化还创造了新的东西。
The shell of a dinosaur egg is built like a motorcycle helmet, able to withstand a severe shock.
恐龙蛋的蛋壳就像一个摩托车头盔，可以承受强烈的冲击。
And then, for even more protection, there's the albumen, or egg white.
要说什么保护作用更大那就是胚乳，也就是蛋白。
The egg white is a kind of a gel and has multiple functions.
蛋白是一种胶体，有多重功能。
One is to keep the embryo that's developing moist, but it also acts as a shock absorber.
一是保持胚胎发育的湿润环境，但它同样扮演了减震器的功能。
Because if the egg gets jarred, you don't want to kill the embryo that's developing by a sudden shock.
因为如果蛋受到冲击，你肯定不想因为瞬间的冲击扼杀正在发育的胚胎。
A well-constructed egg makes it that much more likely that a hatchling will survive.
一颗结构合理的恐龙蛋会使幼崽的成活率大大增加。
And when that youngster grows up,
当幼崽长大之后，
it will pass on those very same genetic traits that saved it in the first weeks of life.
它会把在生命初期拯救了它的遗传性状流传给后代。
Inside this tiny home, a single fertilized cell divides rapidly.
在这个微小的家中受精卵迅速发育。
These cells become a myriad of tissue types that will make up bones, skin, nerves, and organs.
这些细胞分裂成无数的组织型将来成为成骨头，皮肤，神经和器官。
