The frog Rana pipiens jumps through windows to escape confinement even in the absence of both tectums. It will do so towards white windows contrasted to black box sides and black window contrasted to white box sides. A Second Barrier Affects Toad Detour Behavior Figure 5 . From Bufo viridis . Hammer shows toad initial position and orientation.
Dots are the barrier.
Arrows give the percentage of approaches in that direction. The experimental arena was painted black. From Bufo viridis. Barriers are 20 cm long so that when gap is 20 cm the front fence is eliminated. Fence separation is 10 cm, prey lies 12 cm behind rear fence, toad is located 10 cm ahead of gap.