It's a library for doing evolutionary computation in Perl.

Algorithm::Evolutionary was formerly called OPEAL, which is an acronym for
Obvious Pearl Evolutionary Algorithm Library.

The design principles of Algorithm::Evolutionary are:
    * It should be easy to program any kind of evolutionary algorithm; all
      chromosome representations and operators are possible.
    * An XML dialect called EvoSpec is used as a language for description of
      algorithms and for representation of the state of an algorithm. This
      could make Algorithm::Evolutionary interoperable with other EA libraries,
      such as EO or JEO.

See also: http://opeal.sourceforge.net/