One of the greatest mysteries of the history of life is the cambrian explosion .
寒武纪的大爆炸是生命史中最大的谜团之一。
During the cambrian explosion , major paradigm shifts took only tens of millions of years .
在寒武纪生命大爆发期间,主要模式转化只用了数千万年的时间。
The ediacaran fossil record thus stretches the origins of animals to well before the cambrian explosion .
埃迪卡拉化石的发现,将动物的形成时间从寒武纪又推早了不少。
During the cambrian period , 500 million years ago , worm-like creatures were evolving into fish-like creatures .
在5亿年前的寒武纪,似蠕虫生物逐渐演化成似鱼生物。
Animals - including human beings - trace their origins back to the oceans of the cambrian period more than half a billion years ago when the first multicellular organisms that fed exclusively on onther living things appeared .