Late spring, in the Cretaceous Period. Adolescence is a critical time.
白垩纪，暮春时节。青春期是一个关键时期。
Dinosaurs are preparing to mate. Some will succeed. Others will fail.
恐龙们正在为交配做准备。有的会成功，而有的则会失败。
In Darwinian calculus, you can be the finest hunter in the land, and if you can't attract and hold on to a desirable mate with desirable genes, you're a loser.
在达尔文的结论中，你可能会是陆地上最好的猎手，但如果你无法吸引并留住拥有理想基因的合适伴侣，那么你就是个失败者。
A loser whose genes are about come to an abrupt end.
失败者的基因很快会突然终结。
Mating is serious business with significant repercussions.
交配是一项严肃的任务，而且影响重大。
A male looking at females and a female looking at a male...what they're doing, without actually thinking it consciously, is evaluating the potential genes over there.
雄性和雌性相互打量着对方，它们的这种无意识的举动其实就是在评估对方的潜在基因。
"Are your genes good ones? Will your genes mixed with my genes make really healthy, very competitive youngsters?"
"你的基因优秀吗？我们的基因结合后会生出健康的，极具竞争力的孩子吗？"
Clues that males are approaching sexual maturity abound.
雄性恐龙进入性成熟期的迹象有很多。
The crest on an adolescent Parasaurolophus is now fully developed.
处于青春期的副栉龙的头冠已经发育完全。
Triceratops' horns have grown from little stubs pointing backwards to lethal weapons pointing forward.
三角龙的角已从朝向后方的"小树桩"长成了直指前方的致命武器。
And Tyrannosaurus Rex has staked claim to a territory of his own.
雷克斯霸王龙已建立了自己的领地。
Males soon to be adults fight for the chance to prove they are the best.
即将成年的雄性恐龙会争取一切机会来证明自己才是最优秀的。
Females choose carefully. Only the strongest, fittest, or most intelligent males will do.
而雌性恐龙则会仔细挑选。只有最强壮，最健康或最聪明的雄性恐龙才会被选中。
And when it comes to reproducing, something else is critical...timing.
在繁殖的时候还有一件事也很关键...时机。
Most big predators today breed on a short interval in a year, actually most animals today.
今天的多数大型食肉动物都只在一年中的某段时期繁殖，其实如今大多数动物都这样。
Breed only on a short interval, a couple of days or a week or two.
繁殖期很短，只有几天或一到两个星期。
Outstanding exception being that the peculiar predatory species, homo sapiens.
但有一个特殊的食肉物种是个例外，那就是人类。
