There has been renewed interest in using simulated evolution to addres
s difficult optimization problems. These simulations can be divided in
to two groups: (1) those that model chromosomes and emphasize genetic
operators; and (2) those that model individuals or populations and emp
hasize the adaptation and diversity of behavior. Recent claims have su
ggested that genetic models using recombination operators, specificall
y crossover, are typically more efficient and effective at function op
timization than behavioral models that rely solely on mutation. These
claims are assessed empirically on a broad range of response surfaces.