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Different viewpoints, many with deep philosophical and historical
roots, have shaped the scientific study of the origin of life. Some of these argue that
primeval life was based on simple anaerobic microorganisms able to use a wide
inventory of abiotic organic materials (i.e. a heterotrophic origin), whereas others
invoke a more sophisticated organization, one that thrived on simple inorganic molecules
(i.e. an autotrophic origin). While many scientists assume that life started as
a self-replicative molecule, the first gene, a primitive self-catalytic metabolic network
has also been proposed as a starting point. Even the emergence of the cell
itself is a contentious issue: did boundaries and compartments appear early or late
during life's origin? Starting with a recent definition of life, based on concepts of
autonomy and open-ended evolution, it is proposed here that, firstly, organic molecules
self-organized in a primordial metabolism located inside protocells. The
flow of matter and energy across those early molecular systems allowed the generation
of more ordered states, forming the cradle of the first genetic records. Thus,
the origin of life was a process initiated within ecologically interconnected
autonomous compartments that evolved into cells with hereditary and true
Darwinian evolutionary capabilities. In other words, the individual existence of life
preceded its historical-collective dimension.
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