CORRELATION BETWEEN SURVIVAL DURING FOOD-DEPRIVATION AND SEARCH BEHAVIOR IN POPULATIONS OF DROSOPHILA-MELANOGASTER

Search behaviour and survival during food deprivation were compared in six populations of Drosophila melanogaster derived from field collect ions. Search duration or intensity, as measured by displacement after feeding, number of revisits to the food, and tendency to fly away duri ng food search, vary among the six different populations. Survival tim es during food deprivation, shown here to be a heritable trait, also d iffer significantly among the tested populations. Survival during food deprivation is correlated with displacement and revisits. Flies from populations with shorter displacement values (more intense search) ten d to survive for shorter periods when deprived of food, whereas flies from populations with longer displacement values (less intense search) tend to survive for longer periods when deprived of food. The results support (1) a functional group of locomotory control elements influen cing the outcome of a searching bout, and (2) a negative correlation b etween search intensity and survival during food deprivation and (3) s ignificantly greater variability between than within populations for s earching and survival.