Collective evolution and the genetic code
  A dynamical theory for the evolution of the genetic code is presented, which accounts for its universality and optimality. The central concept is that a variety of collective, but non-Darwinian, mechanisms likely to be present in early communal life generically lead to refinement and selection of innovation-sharing protocols, such as the genetic code. Our proposal is illustrated using a simplified computer model, and placed within the context of a sequence of transitions that early life may have made, prior to the emergence of vertical descent. 
Kalin Vetsigian, Carl Woese and Nigel Goldenfeld (University of   Illinois at Urbana-Champaign)