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arXiv · q-bio/0701023

The cosmological model of eternal inflation and the transition from chance to biological evolution in the history of life: The possibility of chance emergence of the replication and translation systems, and the protein superfolds

Abstract

Evolution of life on earth was governed, primarily, by natural selection, with major contribution of other evolutionary processes, such as neutral variation, exaptation, and gene duplication. However, for biological evolution to take off, a certain minimal degree of complexity is required such that a replicating genome encodes means for its own replication with sufficient rate and fidelity. In all existing life forms, this is achieved by dedicated proteins, polymerases (replicases), that are produced by the elaborate translation system. However, evolution of the coupled system of replication and translation does not appear possible without pre-existing efficient replication; hence a chicken-egg type paradox. I argue that the many-worlds-in-one version of the cosmological model of eternal inflation implies that emergence of replication and translation, as well as the major protein folds, by chance alone, as opposed to biological evolution, is a realistic possibility and could provide for the onset of biological evolution. Hence an RNA world, as it is currently conceived, might have never existed although catalytic activities of RNA were, probably, critical for the onset of biological evolution and its early stages.

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Eugene V. Koonin. 2007-01-16. The cosmological model of eternal inflation and the transition from chance to biological evolution in the history of life: The possibility of chance emergence of the replication and translation systems, and the protein superfolds. https://arxiv.org/abs/q-bio/0701023

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