Without this critical ingredient for life, animals started to suffocate. 没有了这种不可或缺的生命成分 动物开始窒息
For those unable to escape the sludge, there was only one possible outcome. 对于那些无法逃离这脏水的生物来说 结果只有一个
plankton had been the catalyst for animal life. 浮游生物是动物生命的催化剂
and Dunkleosteus had reigned for 20 million years. 邓氏鱼已经统治了2000万年
these fish are balled together for protection. 这些鱼聚集在一起以寻求保护
For these fish, size is everything. 对这些鱼来说 大小决定一切
He also uses them for one of the most intimidating displays in nature... 还用颌来展现令人生畏的实力