New Scientist’s Last Word series invited readers to consider a radically different Earth: one in which anaerobic life is the only form of life. The question, posed in a short item on the magazine’s website, asks how the planet would change if oxygen-dependent organisms did not exist.
The online article gathers answers from readers rather than presenting a single conclusion. Since the responses come from different readers, the piece contains a range of scientific guesses and arguments. There is only one source here, so there is no independent report to compare against.
Still, the central thread of the item is clear: an Earth dominated solely by anaerobic life would be very different from the oxygen-rich world we know. The exact differences, however, depend on which reader’s reasoning is being considered.