HOW LEARNING AND EVOLUTION INTERACT:
    THE CASE OF A LEARNING TASK WHICH DIFFERS FROM THE EVOLUTIONARY TASK


                                 Stefano Nolfi

It  has  been  reported  recently  that  learning  has  a beneficial effect on
evolution even if the learning involved the acquisition of an ability which is
different from the ability for which individuals were selected (Nolfi, Elman &
Parisi, 1994).  This  effect  was  explained  as the result of the interaction
between learning and evolution. In a successive paper, however, the effect was
explained as a form of recovery from weight perturbation caused  by  mutations
(Harvey, 1996, 1997).  In  this  paper I provide additional data that show how
the effect,  at  least  in  the  case  considered  in  the  paper, can only be
explained as  a  result  of  the interaction between learning and evolution as
originally hypothesized.