  Biological macromolecules, proteins and nucleic acids are composed
exclusively of chirally pure monomers. The chirality consensus appears vital
for life and it has even been considered as a prerequisite of life. However the
primary cause for the ubiquitous handedness has remained obscure. We propose
that the chirality consensus is a kinetic consequence that follows from the
principle of increasing entropy, i.e. the 2nd law of thermodynamics. Entropy
increases when an open system evolves by decreasing gradients in free energy
with more and more efficient mechanisms of energy transduction. The rate of
entropy increase is the universal fitness criterion of natural selection that
favors diverse functional molecules and drives the system to the chirality
consensus to attain and maintain high-entropy non-equilibrium states.
