Well, to me both are equal in this case. Eve listened to the words of animal and Adam listened to Eve, both of them had forgotten the words of God. I got the idea of taking decision and choosing friend from this point. And you know snakes can change their skin, so to me this is a symbol of those human being who are in masks.
I believe that God knew it before as He is all knowing. This is a reminder and an example for us to continue an honest life, so that we can be His chosen one to enter into the heaven.
And he who was seated on the throne said, �Behold, I am making all things new.� Also he said, �Write this down, for these words are trustworthy and true.� And he said to me, �It is done! I am the Alpha and the Omega, the beginning and the end. To the thirsty I will give from the spring of the water of life without payment. The one who conquers will have this heritage, and I will be his God and he will be my son. But as for the cowardly, the faithless, the detestable, as for murderers, the sexually immoral, sorcerers, idolaters, and all liars, their portion will be in the lake that burns with fire and sulfur, which is the second death.�
Well, I have studied Bible and other scriptures to get knowledge about different types of faith and religion. I'm sorry, if I said anything that seems wrong to any one.