Radical Study Suggests Life on Earth Arose Twice

A new study published in Science Advances suggests that life on Earth may have originated twice independently, with bacteria and archaea each developing metabolism separately rather than inheriting it from a common ancestor. Researchers found that the enzymes catalyzing the chemical reactions necessary for life are fundamentally different between these two lineages, indicating they crossed the threshold from non-living to living matter through distinct pathways. The findings challenge the traditional view of a single origin of life, though defining what constitutes "life" itself remains scientifically complex.