  We give a overview of stochastic models of evolution that have found
applications in genetics, ecology and linguistics for an audience of
nonspecialists, especially statistical physicists. In particular, we focus
mostly on neutral models in which no intrinsic advantage is ascribed to a
particular type of the variable unit, for example a gene, appearing in the
theory. In many cases these models are exactly solvable and furthermore go some
way to describing observed features of genetic, ecological and linguistic
systems.
