Near-resonant diurnal reactions: A physical model applicable to origin of life processes

Abstract

We adopt that the large residual chemical potential energy (CPE) among reagents of the biosphere constitutes the key physical problem posed by life. We associate the formation of this CPE with the nearresonant behaviour of a two-stage 'A-B' molecular process that behaves as a self-sustaining parametric oscillator. Under suitable conditions, such an oscillator generates CPE when forced by a periodic (daily) insolation. The net growth factor required to explain the current mean excess of biospheric CPE is ?5×10 -12 d -1 . This aligns with the mean exponential coefficient of secular oxygen generation in the terrestrial atmosphere. It is also consistent with a feasible scale of oxygen production in certain prebiotic natural photosynthesis scenarios, that can be candidates for the initial A subprocess on the Earth. We schematize initial evolutionary development of the A-B process, including the important role of the intermediate AB compound that provides negative feedback. Supportive C-type molecules also develop as a by-product. The diurnally related distribution of H 2 O 2 on Mars may illustrate a comparable proto-biospheric scheme, and there may be analogous processes on Jupiter. The exponential growth in the lengths of terrestrial nucleotide chain molecules also supports its validity, as does the corresponding growth in measures of cellular complexity. We compare the scenario's implications with biological evidence on the possible co-evolution of blue-light photoreception and circadian timing in Archean photoautotrophs. We consider how a surviving level of cellular organization of circadian rhythmicity, from ancient through to modern times, may be interpreted along these lines, comparing our model with a previously published, comparable, biochemical one.