Fossil isotopes reveal life’s diversity 3.5 billion years ago
By 
Anthony King2017-12-20T12:03:00
Early microbes evolved distinct metabolisms based around hydrogen sulfide and methane
A study of some of the oldest fossils on Earth suggests life was already diverse around 3.5 billion years ago. Analysis of the stable carbon isotopes of fossilised microbes from Australia suggests some carried out a primitive form of photosynthesis using hydrogen sulfide, while both methane-producing and methane-consuming microbes were also around.