Comparison between strains to perform aggregation. The design of the apparatus is drawn in the top panel and the protocol is described in the Methods section. Briefly, we analyzed the kinetics of accumulation of flies in two tubes placed in a chamber. Flies enter through the holes to reach food but in one system there is no access. We measured the time necessary for flies to "correct their mistake" and aggregate in the "reward" tube. Two hundred male and female flies (5 days old) were released into the chamber and the total aggregate (flies in the two systems: the accessible and the inaccessible) versus the total in the chamber at each time and for each strain is represented. We observed no statistically significant difference (Student's t test). Values are mean ± SEM (n = 10).