The question of the origin of life was probably asked as soon as humans developed self-consciousness. Our ancestors realized very early that plants, animals, and humans, are distinct from non-living entities on Earth such as rocks, water, and air. Where did life come from? The universally common explanation among early civilizations was supernatural intervention. Almost all early cultures and ancient civilizations believed that they owed their existence to a supreme being, who also created the Earth and other celestial bodies.