These animals were not as sensitive to climate changes in the Cretaceous period as they are today.

这些动物在白垩纪对气候变化不像今天这样敏感。

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Changes in climate before the Cretaceous period caused severe fluctuation in sea level, resulting in the extinction of the dinosaurs.

白垩纪以前的气候变化导致了海平面的剧烈波动，引发了恐龙的灭绝。

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Not exactly outer space then, or the Cretaceous period.

而并不是外太空或是白垩纪。

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Scientists say it formed when high sea levels flooded the middle of North America, splitting the continent in two for millions of years during the late Cretaceous period.

VOA: special.2010.10.05

The Tyrannosaurus lived in North America during the late Cretaceous Period.

VOA: special.2009.09.01

About 70 million years ago, during the Cretaceous period, Lenny and a bunch of friends snuck out of the house to go tip over some Hadrosaurs that were grazing in a field in modern-day Mongolia.

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The moment most people were persuaded that the dinosaurs were killed by an impact was when the crater in Mexico was shown to have been created 65m years ago, at the end of the Cretaceous period.

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Its detection at unearthly levels in rocks 65 million years old was the first evidence in the case for an asteroid causing the mass extinction and global environmental mayhem that ended the Cretaceous period and began the Tertiary period.

BBC: Leaving our mark: Fossils of the future