1. Editorial Introduction

   • Wolfgang Banzhaf

   Editorial Introduction Pages: 5 - 6

2. Barrier Trees on Poset-Valued Landscapes

   • Peter F. Stadler
   • Christoph Flamm

   OriginalPaper Pages: 7 - 20

3. An Empirical Study of Multipopulation Genetic Programming

   • Francisco Fernández
   • Marco Tomassini
   • Leonardo Vanneschi

   OriginalPaper Pages: 21 - 51

4. Genetic Programming Experiments with Standard and Homologous Crossover Methods

   • James V. Hansen

   OriginalPaper Pages: 53 - 66

5. Crossover in Grammatical Evolution

   • Michael O'Neill
   • Conor Ryan
   • Mike Cattolico

   OriginalPaper Pages: 67 - 93

6. Book Review: Evolutionary Robotics: the Biology, Intelligence, and Technology of Self-Organizing Machines

   • Takashi Gomi

   BookReview Pages: 95 - 98