Nature realizes a vast array of complex structures composed of molecular building blocks, the electronic structure of which can be fully described by quantum mechanics. In photosynthetic light harvesting, for example, quantum behavior within complex nanoscale networks has generated tremendous recent interest, yet the exact relationship between structure and quantumness (e.g., vibronic coherence) remains a topic of debate. In this talk, I present a physicist’s perspective on photosynthesis, as laid out by several pioneering quantum physicists including Erwin Schrödinger and George Gamow. I then describe a new paradigm – based on internal thermodynamic fluctuations, or noise – that attempts to describe highly efficient light energy harvesting in complex networks. By understanding the connection between electronic structure and noise, I describe an intrinsic regulation mechanism that emerges from quantum structure alone. This natural regulation process requires no electronic coherence, and is robust across a wide range of energy and length scales. Beyond gaining a deeper understanding of quantum optoelectronics, the natural regulation process described here promises to have applications across various disciplines ranging from quantum nanoscience and computing to bionanoscience and astrobiology. Natural regulation may also explain the predominance of green plants on Earth.