- danger was never far away.
危险永远不会离得太远 - The discarded skin of their ancient adversary.
它们古老对手的蜕皮 - The snake.
蛇 - Snakes evolved around the same time as the first true mammals.
蛇的进化时间 与第一批真正的哺乳动物大致相同 - They lost the arms and legs of their reptilian ancestors
它们失去了爬行动物祖先的四肢 - and developed a streamlined body...
并发展出流线型身体 - making them perfectly adapted to hunting in burrows
使它们完全适应了在洞穴中捕猎