well first of all DeathAngel is wrong (sorry), the big bang didn't just go boom and there was the earth. It took a lot of time (billions of years) for the elements to even form and combine into anything that looks like matter. As for life on earth either someone who is all powerful, all knowing and obviously very friendly zapped earth and said something like "day 1 - create earth" or it was a mixture of chemicals bonding together into life..
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