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I HAVE BEEN planning on writing this post for quite a while and hope to do the topic justice. The Cambrian explosion refers to the sudden radiation of metazoan life during the Cambrian period, and is usually placed between about 540-530 million years ago. It is often said that during the Cambrian explosion all of the modern phyla appeared. This statement has been seized upon by creationists who claim that the Cambrian explosion proves a sudden supernatural creation of life, rather than evolution of organisms over time.

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