A rocky start – mineral crushing as a precursor to life

The origin of life is still highly contested. Some of the hypotheses are seeding from space (panspermia), a hot start to life in hydrothermal vents and lightning strikes on a “primordial soup” (abiogenesis). Here a new hypothesis is introduced: mechanochemical reactions, initiated by meteorite impacts, formed the building blocks of life. Roughly 4.1 to 3.8 billion years ago, a cataclysmic event, called the Late Heavy Bombardment, showered Earth with meteorites. Shortly after, ~3.7 billion years ago, the first evidence of life on Earth is found. Rock crushing has been shown to generate a range of compounds associated with prebiotic life, such as methane, ammonium and simple organic acids. Here we suggest that the abrasion of Earth rocks by meteorites generated these precursors to life. These could then assemble into more complex configurations in other primordial environments, such as hydrothermal vents, so unifying the hypotheses of panspermia, abiogenesis and a hot start to life.