they formed the largest living structure our planet has ever seen... 形成地球史上最大的生物结构
there had been hundreds of ancient species living in the trees, 树上居住着数百种古老的物种
Every living thing within a thousand kilometers 一千公里范围内的一切生物
Living in a group has other advantages too, 一起生活还有其它优势
Today's reptiles are such experts at living in the margins, 今天的爬行动物如此擅长在边缘生存
And yet, living in the same prehistoric swamps, 然而在同一片史前沼泽之中
they are the tallest living things to have ever existed. 是史上最高的生物
But what it produced was a tiny single living cell. 但它产生了一个微小的单细胞生命体