Spontaneous Symmetry Breaking in Directed Percolation with Many Colors:   Differentiation of Species in the Gribov Process
  A general field theoretic model of directed percolation with many colors that is equivalent to a population model (Gribov process) with many species near their extinction thresholds is presented. It is shown that the multicritical behavior is always described by the well known exponents of Reggeon field theory. In addition this universal model shows an instability that leads in general to a total asymmetry between each pair of species of a cooperative society. 
H.K. Janssen