- Life is good.
生命很美好 - But these mammal ancestors
但这些哺乳动物的祖先 - have had little competition or predators,
几乎没有竞争对手和捕食者 - until now.
直到这一刻的到来 - With the planet recovering,
随着地球的复苏 - some reptiles have grown to epic proportions.
一些爬行动物长得异常巨大 - This is an Erythrosuchid.
这是引鳄