LUCA is an abbreviation of the ‘Last Universal Common Ancestor’. The LUCA was a microorganism which lived around 4 billion years ago. The evidence had shown that the LUCA was lived deep underground in hydrothermal vents. These vents were rich in iron-sulphur. It did not use air but made its food from the metal-rich environment surrounding it. It made organic compounds such as ammonia for its metabolism from elements such as hydrogen, carbon dioxide and nitrogen.
