Fig. P1.

(A) GPS device placed on the back of an Egyptian fruit bats. Photo credit: A. Tsoar. (B) Flight trajectory of a bat leaving the cave, flying locally (light gray line), then taking a long commuting flight to the feeding tree (black line) and then back to the cave (dark gray). Bats flew at very straight trajectories, and returned to the same favorite feeding-trees night after night. (C) Bat that was released in the Negev desert in Israel, inside a deep erosional crater that is surrounded by cliffs approximately 300-m high. Note the tortuous disoriented flight (green): this bat flew almost 34 km before it eventually left the crater and turned toward the familiar area. (D) Bats that were released from a high mountain at the crater edge have homed straight (blue line), in contrast to the disoriented flights of bats released inside the crater (green), suggesting an important role for vision in Egyptian fruit bat navigation. C, view from northeast; D, view from north-northeast.