The early Cretaceous fossils that we find in Maryland are preserved in sandstones and clay-stones.

我们马里兰发现白垩早期化石保存砂岩和粘土岩中。

To find such living fossils from as far back as the Cretaceous is extraordinary.

能发现白垩化石是非同了不起。

It lived in coastal wetlands more than 66 million years ago during Earth's Cretaceous Period.

它6600多万年前地球白垩时期沿海湿地中。

The oldest-known ant fossil dates back about 100 million years to the Cretaceous Period.

已知最古老蚂蚁化石可以追溯到大约1亿年前白垩时期。

Castillo said during the Creataceous, marine turtles had increased body sizes.

卡蒂略说，白垩时期，海龟体型增大了。

Predators of Cretaceous are gigantic by our standard.

我们看来白垩肉动物都是巨大。

All these Cretaceous plant eaters, with their complicated apparatus, they're all much more sophisticated.

所有这些白垩草动物都有其复杂防御器官，它们都是很高级物。

That happened 66m years ago, at the end of the Cretaceous period.

这一切就发6600万年前白垩末期。

It lived about 72 million years ago during a period of time called the Cretaceous Period.

它大约7200万年前白垩时期。

Quetzalcoatlus would make all other animals in the Late Cretaceous stare.

披羽蛇翼龙能让白垩晚期其他动物汗毛倒立。

Over the next 90 million years, a new era called the Cretaceous period dawned.

接下来九千万年里，开始了一个叫做白垩新时期。

That is fair enough. Such landscapes were common during the beasts' heydays, the Jurassic and Cretaceous periods.

这很合理，因为这样景观侏罗和白垩野兽鼎盛时期很常见。

During the Cretaceous period, 140 million years ago, this dinosaur sported a neck of dangerous looking spines.

一亿四千万年前白垩，这种恐龙脖子上长着看起来很危险刺。

It was lightweight and lived during the Cretaceous Period, about 75 million to 81 million years ago.

它重量很轻，大约7500万到8100万年前白垩时期。

There were different diving birds during the Cretaceous, including North America's Hesperornis, which reached about 1.8 meters long.

白垩有不同潜鸟，包括北美长翅鸟，它长达1。8米左右。

The earliest known bird, Archaeopteryx, lived during the Jurassic, the period before the Cretaceous.

人类所熟知最古老鸟类始祖鸟白垩时期之前侏罗时期。

Well, Edmontosaurus was sort of the Wildebeest of the Cretaceous plains.

埃德蒙顿龙就好像是白垩平原上牛羚。

The findings suggest large sizes in marine turtles developed independently in separate Cretaceous lineages in North America and Europe.

研究结果表明，北美和欧洲不同白垩谱系中，体型较大海龟独立发育。

When finished they found that they had more than tripled the global total of dinosaur fossils from the late Cretaceous.

当工作结束时候，他们发现自己已经——为这颗行星——把白垩末期恐龙化石增加了两倍多。

The best-documented such impact took place 65 million years ago at the end of the Cretaceous period of geological history.

记载最完整这种灾难曾发6500万年前，地质历史阶段白垩末期。