abiogénesis

Abiogenesis is the scientific hypothesis that life arose naturally from non-living matter. This process is thought to have occurred on early Earth through a series of gradual chemical reactions. The initial stages likely involved the formation of simple organic molecules from inorganic precursors, driven by energy sources such as lightning, volcanic activity, or ultraviolet radiation. These simple molecules, such as amino acids and nucleotides, could have then polymerized to form more complex structures like proteins and nucleic acids.

The next critical step would have been the self-assembly of these molecules into structures that could replicate and maintain themselves. Protocells, early membrane-bound structures containing self-replicating molecules, are a key concept in abiogenesis theories. These early cells would have been very simple, lacking the complex machinery of modern cells. Over vast periods of time, through processes of natural selection, these protocells would have evolved into the more sophisticated life forms we see today.

While the exact pathway of abiogenesis remains an active area of research, several key experimental findings support the plausibility of the hypothesis. Experiments like the Miller-Urey experiment demonstrated that organic molecules could be synthesized under simulated early Earth conditions. Further research has explored the potential for self-assembly of lipid membranes and the catalytic properties of RNA (the "RNA world" hypothesis). The study of abiogenesis seeks to understand the transition from chemistry to biology, filling the gap between the non-living and the living.