Foraging Behavior of Fruit Flies (Drosophila Melanogaster) On Sugar Patches in 3-D

Abstract

Fruit flies (Drosophila melanogaster) are an excellent model organism to study the neural basis of behavior. An important function of the central nervous system is to process conflicting information and produce a response that increases the probability of survival of the animal. This decision making process can be studied on fruit flies feeding on patches of sugar in the laboratory. We present here preliminary results and a proposal to study the effect of gravity and orientation on foraging choices of flies in a three-dimensional setting. The ability of fruit flies to walk on vertical and inverted surfaces allows them to forage for food on inverted patches and on vertically placed patches at various angles of inclination. Our preliminary tests show that the flies feed at the same rate when foraging on two food patches facing up (67% feeding) as on two patches facing down (70%). When one patch faces up and the other faces down, only 44% of the flies feed. However, in all cases tested, the flies prefer the higher concentration of sugar, regardless of patch orientation. This suggests that patch orientation affects the locomotion aspect of foraging but not the feeding decision once the patch is located. To further test this hypothesis, we plan to use food patches that are spherically shaped, patches oriented vertically, and patches on a sloped diagonal plane.