mammals have evolved an extraordinary solution. 哺乳动物 已经进化出一种非凡的解决方案
The asteroid had inflicted devastating losses on the mammals... 小行星碰撞 对哺乳动物造成毁灭性的打击
...that early mammals were confined to the shadows. 以至于早期的哺乳动物只能躲在暗处
mammals came from humble beginnings... 哺乳动物出身卑微
It was time for the rise of the mammals. 哺乳动物崛起的时候到了
In the clearing, a herd of early mammals graze. 空地上 一群早期哺乳动物在吃草
For tiny mammals, nowhere is safe. 对于小型哺乳动物来说 哪里都不安全