They've been playing this game since the dawn of the dinosaurs. 它们从恐龙时代初期 就开始玩这个游戏
in this instance, the mammals win out. 这次哺乳动物胜出
this saw ornithischians, like Maiasaura, 导致慈母龙这样的鸟臀
This is the only example of animals, 使用药物来挽救其他个体的生命
The casualties in this age-old battle rapidly mount up. 这场古老战斗的伤亡迅速增加
means this branch of dinosaurs, the theropods, 意味着恐龙的这个分支兽脚