恐爪龙被叫做迅猛龙，是地球上有史以来最凶狠的恐龙之一。

　　Forensic examination of the scientific evidence has revealed that this cunning carnivore may have attacked in packs.

　　科学证据的现场检验揭示了这种狡黠的食肉动物可能成群捕猎。

　　They were the Earth's largest animals.

　　它们曾是地球上最大的动物。

　　New technology and forensic evidence helps paleontologists bring to life some of their final moments.

　　新的科技和现场证据帮助古生物学家们重现它们生命中的最后时刻。

　　More than 100 million years ago, Europe, Asia, Africa and North America fractured into large, drifting islands.

　　一亿多年前欧洲、亚洲、非洲和北美洲分离后变成各自漂移的巨岛。

　　It's the early Cretaceous period.

　　白垩纪早期。

　　The terrain rumbled with constant volcanic activity, hurling millions of tons of carbon dioxide into the air and raising global temperatures.

　　永无休止的火山活动震撼着大地，千百万吨二氧化碳被抛到空中，致使全球温度飙升。

　　The eruptions also created ridges rising hundreds of meters from the sea floor.

　　火山爆发还形成了海底数百英尺的山脊。

　　40% of the continents were flooded.

　　40%的陆地被淹没。

　　Water settled into a western interior sea flowing from the Arctic Ocean to the Gulf of Mexico.

　　水从北冰洋流入墨西哥湾聚集成一条西部内陆海道。

　　North America was split in two.

　　将北美洲一分为二。

　　At the end of the Jurassic period, large dinosaurs like Allosaurus and Ceratosaurus vanished.

　　在侏罗纪末期，像异特龙跟角鼻龙这样的大恐龙都已不见踪迹。

　　In their place came new species, better able to adapt to the dramatic environmental changes, increasing humidity and soaring temperatures.

　　它们原来的领地上出现了能更好适应环境剧烈变化的新物种，能忍受湿度的增加和温度飙升。

　　In what's now the state of Montana, herds of giant herbivores migrated across rocky terrain, surrounded by dense forests.

　　在现今是蒙大拿州的地方，成群的巨型食植动物在危险的岩地间穿梭，那里密林环绕。

　　Perfect prey for coordinated killers.

　　它们是杀手们合作狩猎的绝佳对象。