What does snake symbolize?

I'm researching this now, and finding that the best interpretations come from the earliest civilizations. Predominantly, it is a symbol for rebirth because of the snake's shedding of skin. The shedding of a snake's skin highlights the notion of life, death and rebirth. According to Native American beliefs, it is the energy of wholeness, the knowledge that all things are equal and the notion that good things do come of bad. It also represents the ability to experience anything without resistance. For individuals, they believe snakes represent the fact that we're all universal beings. It can also signify the need to transmute thoughts, actions or desires.

The best of the interpretations, from the earliest indiginous cultures, use it to represent transmutations, life's energy and healing. As the civilizations become more complex (like Egyptian to modern first form of the Mason's apron), the symbol becomes more unique to the context or culture. In Jewish or Christian cultures, the snake invokes the forbidden knowledge and the source of evil.