Thermal Life (IMAGE) Virginia Tech Caption Scientists studying methane-producing microbes, like the ones found in deep-sea hydrothermal vents, discovered that a protein critical to photosynthesis likely developed on Earth long before oxygen became available. Credit Virginia Tech Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.