Jennifer Glass lab at Georgia Tech (IMAGE) Georgia Institute of Technology Caption Co-principal investigator Jennifer Glass in her lab at Georgia Tech. She is holding a piece of sedimentary rock full of iron that rusted out of the ocean when breathable oxygen filled Earth's waters and air. Before there was ample breathable oxygen, chemically active iron was very available and very likely was involved in early evolution. It has since become less prevalent in many living systems. Credit Georgia Tech / Allison Carter 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.