Animal Sonar Systems NATO ADVANCED STUDY INSTITUTES SERIES A series of edited volumes comprising multifaceted studies of contem­ porary scientific issues by some of the best scientific minds in the world, assembled in cooperation with NATO Scientific Affairs Division_ Series A: Life Sciences Recent Volumes in this Series Volume 22 - Plant Regulation and World Agriculture edited by Tom K. Scott Volume 23 - The Molecular Biology of Picornaviruses edited by R. Perez-Bercoff Volume 24 - Humoral Immunity in Neurological Diseases edited by D. Karcher, A. Lowenthal, and A. D. Strosberg Volume 25 - Synchrotron Radiation Applied to Biophysical and Biochemical Research edited by A. Castellani and I. F. Quercia Volume 26 - Nucleoside Analogues: Chemistry, Biology, and Medical Applications edited by Richard T. Walker, Erik De Clercq, and Fritz Eckstein Volume 27 - Developmental Neurobiology of Vision edited by Ralph D. Freeman Volume 28 - Animal Sonar Systems - edited by Rene-Guy Busnel and James F. Fish Volume 29 - Genome Organization and Expression in Plants edited by C. J. Leaver Volume 30 - Human Physical Growth and Maturation edited by Francis E. Johnston, Alex F. Roche, and Charles Susanne Volume 31 - Transfer of Cell Constituents into Eukaryotic Cells edited by J. E. Celis, A. Graessmann, and A. Loyter Volume 32 - The Blood-Retinal Barriers edited by Jose G. Cunha-Vaz Volume 33 - Photoreception and Sensory Transduction in Aneural Organisms edited by Francesco Lenci and Giuliano Colombetti The series is published by an international board of publishers in con­ junction with NATO Scientific Affairs Division A Life Sciences Plenum Publishing Corporation B Physics London and New York C Mathematical and D. Reidel Publishing Company Physical Sciences Dordrecht, Boston and London D Behavioral and Sijthoff & Noordhoff International Social Sciences Publishers E Applied Sciences Alphen aan den Rijn, The Netherlands, and Germantown U.S.A. Animal Sonar Systems Edited by Rene -Guy Busnel Ecole Pratique des Rautes Etudes Jouy-en-Josas, France and James F. Fish Sonatech, Inc. Goleta, California PLENUM PRESS. NEW YORK AND LONDON Published in cooperation with NATO Scientific Affairs Division Library of Congress Cataloging in Publication Data International Interdisciplinary Symposium on Animal Sonar Systems, 2d, Jersey, 1979. Animal sonar systems. (NATO advanced study institutes series: Series A, Life sciences; v. 28) Symposium sponsored by the North Atlantic Treaty Organization and others. Bibliography: p. Includes indexes. 1. Echolocation (Physiology) - Congresses. I. Busnel, Rene Guy. II. Fish, James F. III. North Atlantic Treaty Organization. IV. Title. V. Series. QP469.157 1979 599'.01'88 79-23074 ISBN -13: 978-1-4684-7256-1 e-ISBN-13: 978-1-4684-7254-7 DOl: 10.1007/978-1-4684-7254-7 This work relates to Department of the Navy Grant NOOOI4-79-G-0006 issued by the Office of Naval Research. The United States Government has a royalty-free license throughout the world in all copyrightable material contained herein. Proceedings of the Second International Interdisciplinary Symposium on Animal Sonar Systems, held in Jersey, Channel Islands, April 1-8, 1979. © 1980 Plenum Press, New York A Division of Plenum Publishing Corporation 227 West 17th Street, New York, N.Y. 10011 Softcover reprint of the hardcover 1st edition 1980 All rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permission from the Publisher • 1.£5 ~!,5teme5· 5 --= o R G A N I Z I N G COM MIT TEE - R.G. Busnel - G. Neuweiler Laboratoire d'Acoustique Animale Department of Zoology E.P.H.E. - I.N.R.A. - C.N.R.Z. University of Frankfurt 78350 Jouy-en-Josas, France D-6000 Frankfurt, F.R.Germany - J.F. Fish - J.A. Simmons U.S. Navy Department of Psychology Naval Ocean Systems Center Washington University Kailua, Hawaii 96734, U.S.A. St. Louis, Mo. 63130, U.S.A. - H.E. Von Gierke Aerospace Medical Research Lab. Wright Patterson Air Force Base Dayton, Ohio 45433, U.S.A. v ACKNOWLEDGMENTS -=-=-=-=-=-=-=-=-=-=-=-=-=-=- This symposium was sponsored by various Organizations, National and International. The organizing Committee would like to thank them and their representatives : - North Atlantic Treaty Organization, N.A.T.O. Advanced Study Institutes Programme - Office of Naval Research of the U.S.A. - United States Air Force - Volkswagen-Stiftung from F. R. of Germany - Ecole Pratique des Hautes-Etudes, Laboratoire d'Acoustique Animale, I.N.R.A. - C.N.R.Z. - 78350 JOUY-en-JOSAS, France vi Preface Thirteen years have gone by since the first international meet­ ing on Animal Sonar Systems was held in Frascati, Italy, in 1966. Since that time, almost 900 papers have been published on its theme. The first symposium was vital as it was the starting point for new research lines whose goal was to design and develop technological systems with properties approaching optimal biological systems. There have been highly significant developments since then in all domains related to biological sonar systems and in their appli­ cations to the engineering field. The time had therefore come for a multidisciplinary integration of the information gathered, not only on the evolution of systems used in animal echolocation, but on systems theory, behavior and neurobiology, signal-to-noise ratio, masking, signal processing, and measures observed in certain species against animal sonar systems. Modern electronics technology and systems theory which have been developed only since 1974 now allow designing sophisticated sonar and radar systems applying principles derived from biological systems. At the time of the Frascati meeting, integrated circuits and technol­ ogies exploiting computer science were not well enough developed to yield advantages now possible through use of real-time analysis, leading to, among other things, a definition of target temporal char­ acteristics, as biological sonar systems are able to do. All of these new technical developments necessitate close co­ operation between engineers and biologists within the framework of new experiments which have been designed, particularly in the past five years. The scientists who have been working on these problems in var­ ious fields (electronics experts, signal processors, biologists, physiologists, psychologists) have produced new and original results, and this second symposium furnished the opportunity of cross-discip­ linary contacts permitting an evaluation of the state of present research. PREFACE The Jersey meeting in April, 1979, brought together mo~e than 70 participants from 8 different countries. This meeting was part­ icularly necessary considering the number of new research groups that have appeared in various fields. I mention in particular: the Federal Republic of Germany, where two young scientists who participated at the Frascati meeting, Gerhard Neuweiler and Hans­ Ulrich Schnitzler, have since become professors and have founded two schools of highly productive research; the United States, where funded by the U.S. Navy, studies on dolphins have spread, to San Diego and Hawaii, given impetus by Bill Powell, Forrest Wood, Sam Ridgway, C. Scott Johnson, Bill Evans, and Ron Schusterman, and where certain of Donald Griffin's most gifted students, such as Alan Grinnell and Jim Simmons, are continuing his work on bats at various universities; Canada, where Brock Fenton is performing outstanding research. Although much research has been carried out in the Soviet Union since 1969-1970, it is most unfortunate that, for reasons independent of their wishes, our colleagues from this country, who have more­ over published several excellent reviews of their work, were not able to participate in our discussions. The tendancy which appeared at Frascati towards a certain zoo­ logical isolation corresponding to a form of animal specialization dominated by either dolphins or bats, has partially regressed, thanks to several physicists'who use both bat and dolphin signals in their theoretical approaches. While this segregation by field still re­ mains a dominant behavior made obviously necessary, up to a certain point, by the different biological natures of these two groups of animals, the phenomenon is aggravated by the use of semantics spec­ ific to each group. Nevertheless, common interests and attempts at mutual understanding which appeared are encouraging and should be congratulated. The proceedings of the Jersey meeting demonstrate the extent to which technology has advanced in the past decade, in performances of transducers, various microphones, hydrophones, as well as in recording apparata, analytical methods, particularly in the use of signal processing techniques, and in the application of new ideas such as time-domain, auditory processing, frequency-domain, Doppler compensation, target-acoustic imaging, and so on. It is also interesting to note to what extent experimental strategies have been refined, and one can only admire the elegance of certain demonstrations carried out on dolphins as well as on bats. Many aspects of the performances of diverse species continue, however, to intrigue us, as they reveal sensory abilities whose fine analysis still eludes us, particularly the central mechanisms which control and regulate them. As an example of this, I would particularly like to mention how enriching was the experience that we were able to have using Leslie Kay's apparatus for the blind, PREFACE ix which gave spatiodirectional sensations analogous to those of a~r­ borne animal sonar systems. I do not doubt in the least that those several minutes will lead to a totally new concept of biosonar pro- blems. As Henning von Gierke pointed out during the last session and in a personal communication, the trends appearing at the Jersey meeting indicate that pattern recognition theory is becoming more and more important to biosonar research, replacing range finding and echo theories as the promising research areas of the future. Pattern recognition specialists should be included in future meet­ ings as well as experts on the spatial frequency analysis of acoustic and visual perception.