Raphael
If you want to go with the story in Genesis, and if you want to believe that a moral choice made by one pair of people would have planetary effects throwing off the rest of the ecosphere, alter the instincts/behaviours of animals, and spawn the appearance of new life-forms, then ask yourself by what mechanism? Was it people that could exert that sort of god-like power?
Maybe we should just agree to disagree on the nature of the creative force.