  Noise is a ubiquitous feature of the physical world. As a result, the first
prerequisite of life is fault tolerance: maintaining integrity of state despite
external bombardment. Recent experimental advances have revealed that
biological systems achieve fault tolerance by implementing mathematically
intricate error-correcting codes and by organizing in a modular fashion that
physically separates functionally distinct subsystems. These elaborate
structures represent a vanishing volume in the massive genetic configuration
space. How is it possible that the primitive process of evolution, by which all
biological systems evolved, achieved such unusual results? In this work,
through experiments in Boolean networks, we show that the simultaneous presence
of error correction and modularity in biological systems is no coincidence.
Rather, it is a typical co-occurrence in noisy dynamic systems undergoing
evolution. From this, we deduce the principle of error correction enhanced
evolvability: systems possessing error-correcting codes are more effectively
improved by evolution than those without.
