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To: Loc123
I appreciate your analogy, however it doesn't apply to this system. In the early Earth--as I have said numerous times--there was relatively infinite energy (relative to the magical self-replicating molecules). Therefore, there was no selective pressure on those molecules to compete.

You seem to be pulling difficulties out of nowhere here. Is there some reason I'm wasting my time, that you're absolutely positively never going to accept a mechanistic, chemical, non-magical version of where life comes from? This is getting very lame.

The molecules don't know they're in a competion. It just happens that the first self-replicator is going to inherit the Earth, but nothing on Earth actually knows that. The energy available at any time isn't infinite, and infinite energy would be bad for organic synthesis anyway.

Selective pressures only start after you get imperfect self-replicators making various strains of some original. Then natural selection has something to select. Classic Darwinian evolution begins. Before then it's pretty much blind chemical dumb luck.

209 posted on 11/07/2003 4:30:14 PM PST by VadeRetro
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To: VadeRetro
VadreRetro,

If you present a compelling argument, I will cede the point. Unfortunately, you seem to not have familiarity with chemistry/physics as it relates to endothermic chemicals.

Why would the first self-replicating molecule inherent the Earth?

The energy available at the time is RELATIVELY infinite--notice I noted that term many times for a purpose. If the proscribed environment was the smokestacks, then the energy would be relatively infinite.

Then you say that infinite energy would be bad for organic synth--but without extremely high energies organic synth from non-organic structures would be impossible. This is basic entropy/energy transaction. To create a self-replicating, polymerized, normally unstable configuration of chemicals--all of which describe organic chemicals--you need huge amounts of activation energy or endothermic energy. Without this "pressure" organic molecules that could ever self-replicate would simply bind with inorganic cations, transition metals, or lower energy organic atoms (which have no possibility of self-replication since they are in their lowest energy state).

And how would self-replicators--ideally set for a specific bond, manage to selectively evolve? Basic thermochem shows that it takes enormous external energies to synth larger chemicals. Therefore, the "self-replicators" would likely be small and only slightly endothermic. I don't think there is a hypothetical mechanism yet that would explain why or how they would form relatively (to the first "replicators") complex molecules.

And on the selective pressurs--this is a catch-22 for early replicators. If they (both species or a single, it doesn't matter), had huge amounts of energy and building blocks available, then there would never be any selective pressure. And if the species(es) had suddenly an environment deprived of energy/building block, then they would all decompose due to the inability to bond with the other different (imperfect) self-replicators that had simultaneously utilized the remaining energy/building blocks.

I'm sorry you are getting frustrated, but chemistry is a very precise science--it is not like politics where you can quote an authority and assume credibility unless that authority accounts for inadequecies in his model. In that doctor's model--from what I read and what you posted--there are no proposed solutions to these objections.

Likewise, it appears to me that our increasing knowledge about early Earth chemistry and the nature of life and its precursors (if any) increasing point to the need for an intelligent Agent.
210 posted on 11/07/2003 4:49:07 PM PST by Loc123
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