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For at least the last few meetings we have discussed the idea of LUCA. A name for the evidence that suggests that all life, bacterial, archaeal, and eucaryal, all formed from a common organism. Woese suggests that LUCA, or the root of the universal phylogenetic tree, could not have equivalent metabolically to "modern cells." In his paper, Woese seems to dismiss the idea of a metabolism-first world instead providing evidence for horizontal gene transfer (HGT) in an RNA-first world. While without current supporting evidence, why could a metabolism not support HGT?
Dr. Walker proposed that the argument for metabolism-first or genetics-first ideas often split along the disciplinary lines of scientists. From a thermodynamic point of view, the metabolism-first idea certainly helps account for the energy transfer than must have been taking place in the accepted conditions of early Earth. Energy transfer could help explain the seemingly spontaneous emergence of life from randomness. Looking away from complexities of open and closed systems and how entropy is affected by each, and think of a simple Carnot cycle. Energy goes into a system, the energy is converted, and energy comes out.
Regardless of where on Earth, there was plenty of energy being supplied to our simple system, as discussed. If the simplest building blocks of life, formed from chemical compounds and reactions, were all "floating" about in a primordial soup and energy, in the amount and forms discussed, was being put into the primordial soup-system, would it not be the case that a critical point was reached upsetting equilibrium? At such critical point the material structures of the primordial soup would change. Atoms could align forming crystalline structures or chains. Interstitial atoms might invade the structure of another compound, and such invasion at atomic levels could be the cause of the first transfer! The first transfer might have resulted in the first bacteria, and the following chain of events would evolve to what life is today with the continuous supply of energy transfer that we have.
There has to be some way of accounting for the energy that was being supplied to the system.