Piece difference: simple to evolve?

We detail a study into whether the 'piece difference' heuristic could be evolved for the game of checkers. A co-evolutionary algorithm is used to evolve a piece-weighting system that is used as the evaluation function in a minimax checkers player. The results suggest that the 'piece difference' heuristic will evolve if allowed, but it is not necessarily easy. The work has also demonstrated that other common heuristics can also be evolved.