For all the different combinations, the internal corners significantly

increased the amount of time in proximity to the center (dark edge and dark corner: t = –3.03, P-value = 0.014, df = 31; dark edge and clear internal corner: t = –4.239, P-value = 0.0003, df = 31; clear edge and dark internal corner: t = –17.587, P-value < 0.0001, df = 31). In the first three conditions, the total time in the arena did not significantly affect the percentage of time spent in proximity to the internal corners (clear edge and clear corner: F9, 620 = 0.736, P-value = 0.676; both edge and corner dark: F9, 620 = 0.442, P-value = 0.912; dark edge and clear Inhibitors,research,lifescience,medical corner: F9, 620 = 0.111, P-value = 0.999). However, when the boundary wall is clear and the internal walls are opaque, the flies spend increasingly Inhibitors,research,lifescience,medical more time in close proximity to the internal corners as the exploratory activity phase is attenuated (Fig. 2C; F9, 620 = 2.380, P-value = 0.012). Hence, exploration supersedes

the strong preference for the darkened internal corner. Drosophila also strongly prefer the arena boundary Inhibitors,research,lifescience,medical to the clear internal corners. Figure 2 A time-dependent preference for opaque internal corners. (A). An arena was constructed with two intersecting walls that generated four internal corners. (B). The mean time spent in the 4-cm2 sector in the center of the arena was determined with four combinations … The basis for the Drosophila corner preference was examined further using a circular arena with a radius of 4.2 cm and a 2.56 cm2 recessed alcove (Fig. Inhibitors,research,lifescience,medical 3A). This alcove provided the fly an area further distanced from the arena center, as well as two external 90° corners as additional thigmotactic substrates. This alcove accounts for ~11.5% of the arena perimeter. If the flies Vismodegib cost responded neutrally to the cove compared Inhibitors,research,lifescience,medical to the rest of the boundary, they would be present within this area approximately 6.9 sec/min. Since there appeared to be a significant effect of wall opacity in

driving the fly’s behavior in the previous experiment (Fig. 2), we examined the alcove arena with four Thalidomide sequential experiments, altering the vertical surface that was opaque (Fig. 3). Even when the circular edge of the alcove arena is clear, the flies demonstrate a significant preference for the alcove; an even stronger preference for the alcove is seen when the alcove walls are opaque and the circular edge is clear (Fig. 3B). When the circular edge of the arena was darkened, wild-type flies demonstrated little preference for the alcove and the external corners contained therein (Fig. 3B). Similar to the results with the darkened internal corners, there was a significant interaction between time in the arena and the preference for the darkened alcove (Fig. 3B; F9, 1240 = 7.122, P-value < 0.0001). This alcove preference increases as specific exploration of the novel arena decreases.