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

我们在马里兰发现的垩早期化石保存在砂岩和粘土岩中。

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

能发现垩的活化石是非同了不起的。

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

它生活在6600多万年前地球垩时期的沿海湿地中。

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

卡斯蒂略说，在垩时期，海龟的体型增大了。

Being confined on the island of Madagascar in the late Cretaceous was pretty tough.

在垩的末期，被限制在马达加斯加岛上很艰难。

There is no reason to believe that the dinosaurs were dying out gradually during the last three million years of the Cretaceous, Sheehan reported.

“没有理由认为。在垩的最后300万年里恐龙在渐渐消失。”希恩在报告里说。

But for such a celebrated killer, able to take on the toughest creatures of the Cretaceous, some things just don't add up. It's slow.

但对这个让丧胆能拿下垩最坚韧的生物的杀戮者而言，有一点很不相称。它行动缓慢。

It lived in a dry area about 80 million years ago during the Cretaceous Period, near the end of the age of dinosaurs.

它生活在大约8000万年前的垩，也就是恐龙时代末期的一个干燥地区。

They have thrived since the age of dinosaurs, with the oldest-known ant fossil dating back about 100 million years to the Cretaceous Period.

自恐龙时代以来，它们就一直繁衍生息，已知最古老的蚂蚁化石可以追溯到大约 1 亿年前的垩时期。

A species of dinosaur discovered in an Egyptian desert has shed new light on beasts that roamed Africa in the Cretaceous period.

在埃及沙漠中发现的一种恐龙，为垩漫步于非洲的野兽提供了新的认识。

Paleontologists believe it belongs to a toothless theropod dinosaur, or oviraptorosaur, dating back 72 to 66 million years, within the Cretaceous Period.

古生物学家认为它属于一种无牙兽脚类恐龙，或称卵龙，可以追溯到7200万至6600万年的垩时期。

Some duckbills were 50-feet long, but Ajnabia was perhaps the smallest of these Cretaceous vegetarians, about the size of a pony.

有些鸭嘴兽有50英尺长，但异域龙可能是垩最小的素食者，只有小马那么大。

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

记载最完整的这种灾难曾发生在6500万年前，在地质历史阶段的垩末期。

I think these dinosaurs went extinct because they simply could not deal with the global environmental changes that were occurring at the end of the Cretaceous period.

我想这些恐龙的灭绝是因为它们无法适应在垩末期出现的全球性的环境变化。

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

当工作结束的时候，他们发现自己已经——为这颗行星——把垩末期的恐龙化石增加了两倍多。

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

这很合理，因为这样的景观在侏罗和垩的野兽鼎盛时期很常见。

Different feathers have different patterns of colour, suggesting that Cretaceous dinosaurs-flying or otherwise-used their feathers for display.

不同的羽毛有不同的颜色样式，这表明垩时期的会飞恐龙和陆地恐龙都利用羽毛来炫示自己。

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

在一亿四千万年前的垩，这种恐龙的脖子上长着看起来很危险的刺。

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

类所熟知的最古老鸟类始祖鸟生活在垩时期之前的侏罗时期。

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

已知的最古老的蚂蚁化石可以追溯到大约1亿年前的垩时期。