In the deep-sea hydrothermal vents, where the sun’s light was a myth and the pressure could crush a submarine, lived a community of ancient microbes. Among them was , a humble bacterium who held a secret map in her genetic code: the blueprint for making methionine , the "starter" amino acid for every protein she ever built.
The first group stayed in the boiling, mineral-rich vents. To survive, they kept their methionine synthesis pathway lean and mean. They used the enzyme, a rugged, ancient tool that didn't mind the heat. This lineage became the Archaic Branch , the keepers of the old ways.
One day, the seafloor quaked, opening a rift that swept Meti’s descendants into two very different worlds.