Radical Study Suggests Life on Earth Arose From Non-Living Matter TWICE
The tree of life may split at the roots.
A groundbreaking study published in Science Advances challenges our understanding of how life began on Earth, proposing that the transformation from non-living matter to living organisms may have occurred twice rather than once. Researchers analyzed the fundamental metabolic pathways shared by bacteria and archaea, discovering that these two major lineages possess distinctly different enzymes for performing the same essential chemical reactions. This finding suggests the two groups independently developed their own solutions to enable life, rather than inheriting these capabilities from a common ancestor.
The research, led by biologist William Martin at Heinrich Heine University Düsseldorf, examined the chemical foundations that distinguish living from non-living matter. Scientists believe the earliest cellular precursors relied on metal catalysts naturally present in extreme environments like hydrothermal vents to drive metabolic reactions. Over time, these proto-cells gradually developed their own protein enzymes to perform these functions, reducing their dependence on environmental metals until they became fully independent, living organisms.
The team identified four distinct phases in how catalysis evolved, ultimately determining that bacteria and archaea had already separated before achieving true independence as free-living cells. Each lineage independently evolved the enzymatic machinery necessary for metabolism, representing what researchers characterize as two separate origins of life. While the genetic code itself likely emerged only once, this study suggests life as a functional entity arose through two parallel evolutionary pathways.
Originally reported by Sciencealert →
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