At the Fall in the Garden of Eden, the same way that God's judgment upon Adam affected all mankind, God's judgment upon the serpent affected all reptiles. That is, just as Adam was representative of all mankind, the serpent was representative of all reptiles.
8 And they heard the voice of the Lord God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the Lord God amongst the trees of the garden.
9 And the Lord God called unto Adam, and said unto him, Where art thou?
10 And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself.
11 And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
12 And the man said, The woman whom thou gavest to be with me, she gave me of the tree, and I did eat.
13 And the Lord God said unto the woman, What is this that thou hast done? And the woman said, The serpent beguiled me, and I did eat.
14 And the Lord God said unto the serpent, Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life: