A new study from researchers at the Massachusetts Institute of Technology (MIT) and the Harvard-Smithsonian Center for Astrophysics shows that the first biological molecules on Earth may have originated in shallow lakes that contained large concentrations of sulfites and bisulfites. The paper, “Sulfidic Anion Concentrations on Early Earth for Surficial Origins-of-Life Chemistry,” was published in the journal Astrobiology.
In their study, the team shows that concentrations of sulfidic anions – key ingredients for life – were present in high concentrations around the time of life’s first appearance on Earth some 4 billion years ago. Sulfidic anions, particularly sulfites and bisulfites, may have been abundant in rivers and lakes on the early Earth. The molecules would have originated come from sulfur dioxide in the atmosphere from erupting volcanoes, which eventually settled and dissolved into liquid water reserves.