Higher accuracy due to higher speeds in copying information

Biological information in molecules such as DNA must be copied with both accuracy and speed to be transmitted across generations. Numerous theories have quantified how higher accuracy can be attained at the cost of speed. However, experimental data often shows the opposite trade-off: mutations in proofreading DNA polymerases that increase mutation rates generally reduce speed or processivity. We show how such counter-intuitive trade-offs result from well-studied non-equilibrium proofreading models combined with stalling effects and evolutionary reasoning about the impact of typical mutations. We derive conditions under which proofreading mechanisms can evolve under selection for higher speed alone, without any pressure to reduce mutation rates. Such a relationship has evolutionary consequences, ranging from the origin of life in the RNA world to the evolution of mutation rates in extant populations.