Definition
Abiogenesis
Abiogenesis is the process by which living organisms arise from non-living matter, such as simple organic compounds. It marks the transition from chemistry to life.
Hypotheses
Several theories describe the moment of transition:
- RNA World: Proposes that proto-organisms were organised around RNA molecules, which could both replicate and fold into 3D structures acting as primitive enzymes.
- Metabolism First: Suggests that life began without genes, likely in the rock chimneys of “black smokers” on the ocean floor, using proton gradients as batteries to power self-perpetuating chemical loops (e.g., the reverse Krebs cycle).
Computational Perspective
From a computational standpoint, abiogenesis is the emergence of functional replicators from a “Turing gas”. This occurs through a series of phases:
- Instruction Generation: Individual instructions occasionally generate others.
- Autocatalytic Sets: Cycles of interactions that mutually reinforce each other.
- True Replication: The emergence of short programs that copy themselves using looped instructions.
Obs
Abiogenesis is not a single event but a “weaving together” of many separate strands. The first stable replicator acts as a historical event horizon (the “Last Universal Common Ancestor”), erasing independent traces of the imperfect replicators that preceded it.