Recent studies have demonstrated social hierarchy-like behaviour among fruit flies (Yurkovic). In more complex vertebrates, where this behaviour can be artificially manipulated, social hierarchy has already been used for cognitive studies (Grosenick). Traditional methods of social rank creation and manipulation (Zhou) mostly cannot be applied to insects due to their minute size. In my study, an environment was formulated to foster fly competition between two flies for a specific area. The result of this competition would result in a hierarchical relationship between the two flies.

Different combinations of heating, cooling, light, and darkness to create a spot desired by the flies in an undesirable environment was explored to create a desirable spot within an undesirable environment. A heated environment with a cooled spot was chosen because of the various disadvantages offered by other options. Being the most efficient among some other designs, a hot water bath was used to create a heated environment while a piece of sheet metal drew heat from one small spot within the vial.

Flies showed very clear preference for the cool spot, in comparison to no preference when temperature was not manipulated. Furthermore, when comparing the two flies placed within the thermally manipulated environment, there was a significant difference in regards to their distance to the cool spot. This difference in behaviour demonstrates one fly is dominant over the other. Since otherwise the flies would be very similarly distant to the cool spot.

For a future study, one fly could be weakened by exposure to some mildly disruptive chemicals or temperature to ensure its submission when competing for the cool spot. Another future study may examine if a third fly outside of the vial will observe and remember the competitive

interaction within the vial. If the above two studies turn out successful, social hierarchy can be used as a means to feed fly information and also as a means to assess how they remember and assess the information. In the future social hierarchy may be used to supplement or even replace the currently widely popular choice chambers for insect behavioural studies.