In a flagship study of its type, researchers have come close to pinning down the nature of LUCA: the Last Universal Common Ancestor of all life on earth today.
LUCA…
- lived 4.2 Billion years ago, only a few hundred million years after Earth’s formation: hundreds of millions of years earlier than thought
- was an anaerobe, i.e. lived in an environment devoid of oxygen
- was a thermophile, i.e. tolerated a hot environment
- had a relatively large genome encoding some 2600 proteins
- feasted on hydrogen, quite possibly from hydrothermal vents
- had a rudimentary immune system based on CRISPR-Cas9 genes, to fight invading viruses.