Prey perception.

Perceptual range of insects (10–40 mm) with sufficient target strength for detection at different detection distances. Bars represent the perceptual range of targets based on the frequency range between 15 and 55 kHz, separated into five frequency bands (10–20, 20–30, 30–40, 40–50, and 50–55 kHz). Stars represent sizes of detected prey items at different detection distances based on peak frequencies of molossid calls (including frequency alternations; Table 1, 2, 3). Calling intensity was assumed to be 121 dB SPL, and hearing threshold to be 20 dB SPL. In addition, environmental conditions were assumed to be 25°C, 80% humidity, and 101325 Pascal. The model shows that the perceptual range of targets due to frequencies of 20–40 kHz reaches an optimum at 4–5 m.