Not only most metazoan phyla made their debut at the earliest Cambrian, but also the fossil record like calcareous metaphyte flora and acritarch change dramatically nearly at the same time.
外部圈层的演替变
，诸如大陆重组、磁极移、古气候、大洋学性质的变以
大气氧含量的变
时间上与这一生命爆发事件有耦合关系。
