Biologists have gained important new insights by resolving with near-atomic clarity, the very first core membrane protein structure in the simplest known photosynthetic bacterium, called Heliobacterium modesticaldum (Helios was the Greek sun god). By solving the heart of photosynthesis in this sun-loving, soil-dwelling bacterium, the research team has gained a fundamental new understanding of the early evolution of photosynthesis, and how this vital process differs between plants systems.