[idiot74]

Relevant article:

http://bytesizebio.net/2009/10/11/weekly-poll-replicators-fi...

"Replicators First

Aka RNA World: RNA emerges as the first molecule that can replicate and perform enzymatic processes. It stores information and it is biochemically active. Thus it can both replicate and control a primitive meabolism. Later came the transition to DNA as an information storage, and the enzymatic role was mostly relegated to proteins.The first replicators might not even have been RNA molecules, but some pre-RNA nucleic acid such as PNA or TNA..."

"Metabolism First

Metabolism First holds that metabolic processes assembled prior to the existence of replicators. Günter Wächtershäuser proposed that the pioneer organism originated in high (>100C) temperatures in hydrothermal vents. This organism resembled the catalytic converter in a car, more than a primitive cell: it had a composite structure of a mineral base with catalytic transition metal centers, such as iron-sulfide and nickel-sulfide... "

[posterboy]

How about antagonistic roles for each? They may have existed independently, but joined a feedback loop where the metabolic process draws energy from a replicating process ... or chain reaction of RNA syntheses was the metabolic and replicating process both at once. How about it?