. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ULTRASONIC ECHOES FROM MOTHS 201 dodge, or run, to which the answer seems to be that there is survival value in variety. At present there seems to be no direct way of finding out how much information. a bat obtains from echo fluctuations produced by the wing movements of its prey. In the following experiment the bat was replaced by a source of ultrasonic pulses and a microphone in order to determine how the amplitude and other properties of the echo are affected by the wing movements of flying FIGURE 1. Block diagram
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ULTRASONIC ECHOES FROM MOTHS 201 dodge, or run, to which the answer seems to be that there is survival value in variety. At present there seems to be no direct way of finding out how much information. a bat obtains from echo fluctuations produced by the wing movements of its prey. In the following experiment the bat was replaced by a source of ultrasonic pulses and a microphone in order to determine how the amplitude and other properties of the echo are affected by the wing movements of flying FIGURE 1. Block diagram of apparatus used to record the attitude and echo of a moth in fixed flight. Dotted line, acoustic path; dashed line, optical path, or other details see text. METHOD A block diagram of the apparatus is shown in Figure 1. In the early experi- ments a 35-mm. camera (Exakta) equipped with a 180-mm. telephoto lens framed the tube face of an oscilloscope at a distance of one meter. Half the image of the tube face was occupied by a prism (P) at 50 cm. that served to align the image of the moth next to that of the tube face. Since both images were at the same distance from the camera, the centimeter scale on the tube face (Fig. 2 et seq.} serves both as a time base for the echo trace and a size scale for the image of the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
