Natural electrical circuits can be found in various forms in nature, including phenomena like lightning, static electricity, and the electrical activity in living organisms such as electric fish. Examples of complete circuits occur when dissimilar metals are in contact with electrolytes, as seen in seawater or soil, and during solar storms that induce currents in conductive materials. Lightning serves as a natural example of a closed circuit, where charge builds up in clouds and discharges to the Earth, maintaining overall electrical neutrality. The discussion highlights that all electrical circuits, whether natural or artificial, adhere to the same fundamental laws of physics, including potential, current, and resistance. The complexity and behavior of these circuits can vary significantly, but they fundamentally operate under the same principles.