We probed by simulations the effect that binding of precursors to the replicator fibers has on the error rate during replication as compared to the control where the surface binding is turned off. Fibers elongate by the addition of a new hexamer to the hexamer exposed at its end . For cases (i)-(iii) we considered replication to be accurate when the new hexamer is identical to the previous one. The incorporation of hexamer with a composition that is different to that of the fiber end is considered a mutation. For case (iv), where A preferentially interacts with B, this definition was reversed (see below).