Thanks for the detailed explanation of the mechanism at the molecular level, really helpful! Could you explain how natural selection (NS) gave rise to the development of these complex processes in the electron transport chain? Critically, NS only works if any step in the process provides a selective advantage to the cell. So if a mutation allows the development of the first part of the process where FMNH2 gives rise to QH2 there is no selective advantage because the rest of the electron transport chain has not yet been formed, nor is ATP synthase present, so no ATP can be formed. Is there a plausible explanation of how all these complex intermediate steps in the process of producing ATP were formed by NS, which can only plausibly work one step at a time because of the complexity of each step? This is especially challenging to conceptualize from a NS standpoint when even if the entire electron transport chain was functionally formed, there is still no selective advantage to the cell because the super complex ATP synthase is required to produce the ATP. The electron transport chain and ATP synthase must both be form contemporaneously before there is any selective advantage for NS to work on. I would appreciate an explanation of how this might have happened.
