  The concept of entropy in statistical physics is related to the existence of
irreversible macroscopic processes. In this work, we explore a recently
introduced entropy formula for a class of stochastic processes with more than
one absorbing state that is extensively used in population genetics models. We
will consider the Moran process as a paradigm for this class, and will extend
our discussion to other models outside this class. We will also discuss the
relation between non-extensive entropies in physics and epistasis (i.e., when
the effects of different alleles are not independent) and the role of
symmetries in population genetic models.

Populations and Evolution