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Acoustic imaging in bat sonar: Echolocation signals and the evolution of echolocation

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Summary

Echolocating bats behave as though they perceive the crosscorrelation functions between their sonar transmissions and echoes as images of targets, at least with respect to perception of target range, horizontal direction, and shape. These data imply that bats use a multi-dimensional acoustic imaging system for echolocation with broadband, usually frequencymodulated signals. The perceptual structure of the echolocation signals used by different species of bats was investigated using the crosscorrelation functions between emitted signals and returning echoes as indices of perceptual acuity.

Thebandwidth andaverage period of echolocation signals are identified as the principal acoustic features of broadband sonar waveforms that determine the quality of target perceptions. The multiple-harmonic structure of echolocation sounds, which is characteristic of the broadband signals of the majority of species of bats, yields a lower average period (separation of peaks in the crosscorrelation function) than would be expected from the average frequency of the signal as a whole, sharpening target localization.

The frequency-modulation of the harmonics in the sonar sounds of bats reduces the heights of side-peaks in the crosscorrelation functions of the signals, promoting sharp, unambiguous determination of target position, and leads to the well-known coupling of perception of range and velocity for moving targets. The shapes of the frequency sweeps and bandwidths of frequency modulation contribute to reducing this range-velocity coupling. Harmonic organization nearly eliminates range-velocity coupling.

The use of multiple-harmonics and fairly broad frequency modulation in sonar signals yields especially sharp resolution of target position to reject clutter interference. Such signals are commonly used by bats in cluttered environments. Very broad frequency sweeps with fewer harmonics may accomplish the same effect, but the low signal periodicity contributed by harmonic structure is an important factor in “banishing” side-peaks in the crosscorrelation function from perception.

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Abbreviations

ACR :

autocorrelation function

AMB :

ambiguity diagram

CF :

constant frequency

FM :

frequency modulated

LFM :

linear frequency sweep

LPM :

linear period sweep

XCR :

crosscorrelation function

References

  • Ajrapetjantz, A.I., Konstantinov, A.I.: Echolocation in nature, 2nd ed. Arlington, VA: National Technical Information Service, Report Nos. JPRS-63328-1 and -2 (1974)

  • Altes, R.A.: Sonar for generalized target description and its similarity to animal echolocation systems. J. Acoust. Soc. Am.59, 97–105 (1976)

    Google Scholar 

  • Bendat, J.S., Piersol, A.G.: Random data: analysis and measurement procedures. New York: Wiley 1971

    Google Scholar 

  • Beuter, K.: Systemtheoretische Untersuchungen zur Echoortung der Fledermäuse. Dissertation im Fachbereich Physik der Eberhard-Karls-Universität Tübingen (1976)

  • Bonde, N.: Cladistic classification as applied to vertebrates. In: Major patterns in vertebrate evolution. Hecht, M.K., Goody, P.C., Hecht, B.M. (eds.), pp. 741–804. New York: Plenum Press 1977

    Google Scholar 

  • Bruns, V.: Peripheral auditory tuning for fine frequency analysis by the CF-FM bat,Rhinolophus ferrumequinum. II. Frequency mapping in the cochlea. J. Comp. Physiol.106, 87–97 (1976)

    Google Scholar 

  • Buchler, E.R.: The use of echolocation by the wandering shrew (Sorex vagrans). Anim. Behav.24, 858–873 (1976)

    Google Scholar 

  • Cahlander, D.A.: Echolocation with wide-band waveforms: bat sonar signals. Lexington, MA: MIT Lincoln Laboratory, Report No. 271 (1964)

    Google Scholar 

  • Dalland, J.I.: Hearing sensitivity in bats. Science150, 1185–1186 (1965)

    Google Scholar 

  • Engelmann, G.F., Wiley, E.O.: The place of ancestor-descendant relationships in phylogeny reconstruction. Syst. Zool.26, 1–11 (1977)

    Google Scholar 

  • Gerstein, G.L., Kiang, N.Y.-S.: An approach to the quantitative analysis of electrophysiological data from single neurons. Biophys. J.1, 15–28 (1960)

    Google Scholar 

  • Griffin, D.R.: Comparative studies of the orientation sounds of bats. Symp. Zool. Soc. London7, 61–72 (1962)

    Google Scholar 

  • Griffin, D.R.: Discriminative echolocation by bats. In: Animal sonar systems: biology and bionics, Vol. I. Busnel, R.G. (ed.), pp. 273–300. Jouy-en-Josas, France: Laboratoire de Physiologie Acoustique (1967)

    Google Scholar 

  • Griffin, D.R.: The importance of atmospheric attenuation for the echolocation of bats (Chiroptera). Anim. Behav.19, 55–61 (1971)

    Google Scholar 

  • Griffin, D.R.: Listening in the dark. New Haven, Connecticut: Yale University Press (1958); New York: Dover Publications (1974)

    Google Scholar 

  • Griffin, D.R., Friend, J.H., Webster, F.A.: Target discrimination by the echolocation of bats. J. Exp. Zool.158, 155–168 (1965)

    Google Scholar 

  • Grinnell, A.D.: Neural processing mechanisms in echolocating bats, correlated with differences in emitted sounds. J. Acoust. Soc. Am.54, 147–156 (1973)

    Google Scholar 

  • Grinnell, A.D., Brown, P.: Long-Latency “subthreshold” collicular responses to the constant-frequency components emitted by a bat. Science202, 996–999 (1978)

    Google Scholar 

  • Grinnell, A.D., Schnitzler, H.-U.: Directional sensitivity of echolocation in the horseshoe bat,Rhinolophus ferrumequinum. II. Behavioral directionality of hearing. J. Comp. Physiol.116, 63–76 (1977)

    Google Scholar 

  • Henson, O.W., Jr.: The ear and audition. In: Biology of bats, Vol. II. Wimsatt, W.A. (ed.), pp. 181–263. New York: Academic Press 1970

    Google Scholar 

  • Hill, F.S., Schultheiss, P.M.: Some problems of active sonar signal design. J. Acoust. Soc. Am.51, 1802–1811 (1972)

    Google Scholar 

  • Johnson, R.A., Titlebaum, E.L.: Energy spectrum analysis: a model of echolocation processing. J. Acoust. Soc. Am.60, 484–491 (1976)

    Google Scholar 

  • Long, G.R.: Masked auditory thresholds from the bat,Rhinolophus ferrumequinum. J. Comp. Physiol.116, 247–255 (1977)

    Google Scholar 

  • Long, G.R., Schnitzler, H.-U.: Behavioral audiograms from the bat,Rhinolophus ferrumequinum. J. Comp. Physiol.100, 211–219 (1975)

    Google Scholar 

  • Mills, A.W.: Auditory localization. In: Foundations of modern auditory theory, Vol. II. Tobias, J.V. (ed.), pp. 303–348. New York: Academic Press 1972

    Google Scholar 

  • Neuweiler, G.: Recognition mechanisms in echolocation of bats. In: Processing of complex acoustic signals. Bullock, T.H. (ed.), pp. 111–126. Berlin: Dahlem Konferenzen 1977

    Google Scholar 

  • Novick, A.: Acoustic orientation. In: Biology of bats, Vol. III. Wimsatt, W.A. (ed.), pp. 73–287. New York: Academic Press 1977

    Google Scholar 

  • Peff, T.C., Simmons, J.A.: Horizontal-angle resolution by echolocating bats. J. Acoust. Soc. Am.51, 2063–2065 (1972)

    Google Scholar 

  • Sales, G.D., Pye, J.D.: Ultrasonic communication by animals. London: Chapman and Hall 1974

    Google Scholar 

  • Schnitzler, H.-U.: Die Ultraschall-Ortungslaute der Hufeisen-Fledermäuse (Chiroptera-Rhinolophidae) in verschiedenen Orientierungssituationen. Z. Vergl. Physiol.57, 376–408 (1968)

    Google Scholar 

  • Schnitzler, H.-U.: Die Echoortung der Fledermäuse und ihre hörphysiologischen Grundlagen. Fortschr. Zool.21, 136–189 (1973)

    Google Scholar 

  • Schnitzler, H.-U.: Die Detektion von Bewegungen durch Echoortung bei Fledermäusen. Verh. Dtsch. Zool. Ges., 16–33 (1978)

  • Schnitzler, H.-U., Suga, N., Simmons, J.A.: Peripheral auditory tuning for fine frequency analysis by the CF-FM bat,Rhinolophus ferrumequinum. J. Comp. Physiol.106, 99–110 (1976)

    Google Scholar 

  • Schuller, G., Beuter, K., Rübsamen, R.: Dynamic properties of the compensation system for Doppler shifts in the bat,Rhinolophus ferrumequinum. J. Comp. Physiol.97, 113–125 (1975)

    Google Scholar 

  • Schwartz, M.: Information transmission, modulation, and noise, 2nd ed. New York: McGraw-Hill 1970

    Google Scholar 

  • Simmons, J.A.: The resolution of target range by echolocating bats. J. Acoust. Soc. Am.54, 157–173 (1973)

    Google Scholar 

  • Simmons, J.A.: Response of the Doppler echolocation system in the bat,Rhinolophus ferrumequinum. J. Acoust. Soc. Am.56, 672–682 (1974)

    Google Scholar 

  • Simmons, J.A.: Localization and identification of acoustic signals, with reference to echolocation. In: Recognition of complex acoustic signals. Bullock, T.H. (ed.), pp. 239–277. Berlin: Dahlem Konferenzen 1977

    Google Scholar 

  • Simmons, J.A.: Perception of echo phase information in bat sonar. Science204, 1336–1338 (1979a)

    Google Scholar 

  • Simmons, J.A.: Phylogenetic adaptations and the evolution of echolocation in bats (Chiroptera). In: Proceedings of the fifth international bat research conference. Lubbock, Texas: Texas Tech. University Press 1979b

    Google Scholar 

  • Simmons, J.A., O'Farrell, M.J.: Echolocation by the long-eared bat,Plecotus phyllotis. J. Comp. Physiol.122, 201–214 (1977)

    Google Scholar 

  • Simmons, J.A., Vernon, J.A.: Echolocation: discrimination of targets by the bat,Eptesicus fuscus. J. Exp. Zool.176, 315–328 (1971)

    Google Scholar 

  • Simmons, J.A. Lavender, W.A. Lavender, B.A., Doroshow, C.F., Kiefer, S.W., Livingston, R., Scallet, A.C., Crowley, D.E.: Target structure and echo spectral discrimination by echolocating bats. Science186, 1130–1132 (1974)

    Google Scholar 

  • Simmons, J.A., Howell, D.J., Suga, N.: Information content of bat sonar echoes. Am. Sci.63, 204–215 (1975)

    Google Scholar 

  • Simmons, J.A., Lavender, W.A., Lavender, B.A., Childs, J.E., Hulebak, K., Rigden, M.R., Sherman, J., Woolman, B., O'Farrell, M.J.: Echolocation by free-tailed bats (Tadarida). J. Comp. Physiol.125, 291–299 (1978)

    Google Scholar 

  • Simmons, J.A., Fenton, M.B., O'Farrell, M.J.: Echolocation and pursuit of prey by bats. Science203, 16–21 (1979)

    Google Scholar 

  • Skolnik, M.I.: Introduction to radar systems. New York: McGraw-Hill 1962

    Google Scholar 

  • Smith, J.D.: Systematics of the chiropteran family Mormoopidae. Misc. Publ., Univ. Kans. Mus. Nat. Hist.56, 1–132 (1972)

    Google Scholar 

  • Suga, N.: Feature extraction in the auditory system of bats. In: Basic mechanisms in hearing. Møller, A.R. (ed.), pp. 675–742. New York: Academic Press 1973

    Google Scholar 

  • Suga, N.: Specialization of the auditory system for reception and processing of species-specific sounds. Fed. Proc.37, 2342–2354 (1978)

    Google Scholar 

  • Suga, N., Simmons, J.A., Shimozawa, T.: Neurophysiological studies on echolocation systems in awake bats producing CFFM orientation sounds. J. Exp. Biol.61, 379–399 (1974)

    Google Scholar 

  • Suga, N., Simmons, J.A., Jen, P.H.-S.: Peripheral specialization for fine frequency analysis of Doppler-shifted echoes in the auditory system of the “CF-FM” bat,Pteronotus parnellii. J. Exp. Biol.63, 161–192 (1975)

    Google Scholar 

  • Suthers, R.A.: Vision, olfaction, taste. In: Biology of bats, Vol. II. Wimsatt, W.A. (ed.), pp. 265–309. New York: Academic Press 1970

    Google Scholar 

  • Thrane, N.: The discrete Fourier transform and FFT analysers. Brüel and Kjaer Technical Review1, 3–25 (1979)

    Google Scholar 

  • Woodward, P.M.: Probability and information theory, with applications to radar, 2nd ed. New York: Pergamon Press 1964

    Google Scholar 

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Authors and Affiliations

  1. Departments of Psychology and Biology and Program in Neural Sciences, Division of Biology and Biomedical Sciences, Washington University, 63 130, St. Louis, Missouri, USA

    James A. Simmons

  2. Department of Electrical Engineering, Sever Institute of Technology, Washington University, 63 130, St. Louis, Missouri, USA

    Roger A. Stein

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  1. James A. Simmons
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Simmons, J.A., Stein, R.A. Acoustic imaging in bat sonar: Echolocation signals and the evolution of echolocation. J. Comp. Physiol. 135, 61–84 (1980). https://doi.org/10.1007/BF00660182

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