Voices
And He said, "Who told you that you were naked? Have you eaten from the tree of which I commanded you not to eat?" (Genesis 3:11)
It is interesting to note that Adam and Eve did not think it was strange that a serpent spoke to them. From this we can deduct that before the Fall, man could communicate freely with the creatures, and they with him. The Fall caused the corruption of one of man's greatest gifts—the gift of communication.