Selection for central excitatory state (CES) in the blow fly Phormia regina.

Food-deprived but water-satiated blow flies (Phormia regina) were tested for their central excitatory state (CES) response. Bidirectional selection based on individual differences for CES expression resulted in separate high- and low-CES strains in only one generation in three replicate experiments. This suggest that differences in CES expression are correlated with allelic differences at a single locus. The use fo such selected lines in a component analysis of classical conditioning is discussed.