Cambrian explosion
基礎(chǔ)科學(xué)

        Definition: The Cambrian explosion or Cambrian radiation was the relatively rapidappearance,over a period of many million years,of most major groups of complex animalsaround 530 million years ago,as found in the fossil record.寒武紀生命大爆發(fā)hán wǔ jì shēngmìng d......（本文共 417 字）     [閱讀本文] >>