There's a new evangelist on the road in the bible belt of America, but whereas Michael Dowd once believed in creationism he's now an evangelist for Darwin - and he's not abandoned his Christian faith. Indeed his new book is entitled "Thank God for Evolution" and in it he claims that the marriage of science and religion will transform your life and our world. When Roger spoke to Mr Dowd he put it to him there was a time when he believed evolution was "of the devil". What had happened?

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