Article Contentsp. [73]p. 74p. 75p. 76p. 77p. 78p. 79p. 80p. 81p. 82p. 83p. 84p. 85p. 86p. 87p. 88p. 89p. 90p. 91p. 92p. 93p. 94p. 95p. 96p. 97p. 98p. 99p. 100p. 101p. 102p. 103Issue Table of ContentsBehaviour, Vol. 108, No. 1/2 (Feb., 1989), pp. v-vi+1-195Volume Information [pp. v-vi]Front MatterOn the Acoustic Basis of Recognition of the Mother Hen by the Chick in the Domestic Fowl (Gallus gallus) [pp. 1-9]The Effect of Release Time on the Migratory Behaviour of Baltic Salmon (Salmo salar): Influence of an Annual Time Program [pp. 10-22]Limitations of a Generalist: A Field Comparison of Foraging Snakes [pp. 23-43]Nodding: An Appeasement Behaviour of Pigeons (Columba livia) [pp. 44-56]The Role of Frequency Modulation in the Process of Distress Calls Recognition by the Starling (Sturnus vulgaris) [pp. 57-72]The Effect of the Location of a Simulated Intruder on Responses to Long-Distance Vocalizations of Mantled Howling Monkeys, Alouatta palliata palliata [pp. 73-103]The Relative Growth of Dominant and Subordinate Juvenile Steelhead Trout (Salmo gairdneri) Fed Equal Rations [pp. 104-113]Adult-Weanling Recognition among Captive Meadow Voles (Microtus pennsylvanicus) [pp. 114-124]Variation in the Song of the Aquatic Warbler Acrocephalus paludicola in Response to Playback of Different Song Structures [pp. 125-138]Song Learning in Adult Great Tits (Parus major): Effects of Neighbours [pp. 139-159]Is Being Large More Important for Female than for Male Parasitic Wasps? [pp. 160-195]Back Matter!"#$%&&#'($)&$("#$*)'+(,)-$)&$+$.,/01+(#2$3-(402#4$)-$5#67)-6#6$()$*)-89:,6(+-'#;)'+1,<+(,)-6$)&$=+-(1#2$>)?1,-8$=)-@#A6B$C1)0+((+$7+11,+(+$7+11,+(+C0(")4D6EF$G+/#6$=+("#4$H",(#"#+2.)04'#F$I#"+J,)04B$;)1K$LMNB$O)K$LPQ$DR#SKB$LTNTEB$77K$UV9LMVW0S1,6"#2$SAF$I53**.(+S1#$X5*F$http://www.jstor.org/stable/4534743C''#66#2F$MYPMYPQMLM$LVFZYYour use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available athttp://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unlessyou have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and youmay use content in the JSTOR archive only for your personal, non-commercial use.Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained athttp://www.jstor.org/action/showPublisher?publisherCode=bap.Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printedpage of such transmission.JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact [email protected] is collaborating with JSTOR to digitize, preserve and extend access to Behaviour.http://www.jstor.orgTHE EFFECT OF THE LOCATION OF A SIMULATED INTRUDER ON RESPONSES TO LONG-DISTANCE VOCALIZATIONS OF MANTLED HOWLING MONKEYS, ALOUATTA PALLIATA PALLIATA by JAMES MATHER WHITEHEAD1)2) (Department of Biology, University of North Carolina, Chapel Hill, N.C., U.S.A.) (With 14 Figures) (Acc. 27-VII-1988) Vocal communication among primates serves in part to maintain pat- terns of spatial distribution by means of signals which increase, maintain or decrease distance between groups (MARLER, 1968; KUMMER, 1971). Loud calls, often thought to influence spatial relationships of groups at long range, are found among numerous prosimians (PETTER, 1962; PETTER & CHARLES-DOMINIQUE, 1979), among new world species such as Callicebus moloch (MASON, 1968; ROBINSON, 1979, 1981), C. torquatus (KINZEY & ROBINSON, 1981, 1983), howling monkeys, Alouatta palliata (CARPENTER, 1934, 1965; ALTMANN, 1959; CHIVERS, 1969; EISENBERG, 1976), A. seniculus (SEKULIC, 1981, 1982a, b, c, 1983) and Atelesfusciceps 1) I thank Dr Haven WILEY for stimulation and guidance during this project, Dr Ken GLANDER for sharing his understanding of the howlers of La Pacyfica, and other members of my dissertation committee, Drs Helmut MUELLER, Alan FEDUCCIA and Alan STIVEN, for their comments and support. Drs Carolyn CROCKETT, John EISENBERG, Deborah GORDON, Peter KLOPFER, Douglas RICHARDS, John ROBINSON, Jim RUSSELL, and Peter WASER as well as members of the ecology and behavior groups at the University of North Carolina and Duke University have made constructive comments on this project. Sr Rodrigo MEDELLIN greatly improved the Resumen. For their assistance in the field, I thank Alice BICK, Robert BOTTOME, Sandy MONTOGOMERY, Chris NATIONS and Charles WELCH. For permission to work on their ranch, for their hospitality and for their deter- mination to protect forested areas, I thank Werner and Lilian HAGNAUER and their extended family. Alfredo and Paulina CHACON, Flor TORRES and Dr Donald STONE of the Organization for Tropical Studies gave extraordinary help when I needed it. Sup- ported by a dissertation improvement grant BNS-80-13053 from the National Science Foundation, a Research Initiation and Support grant from N.S.F. and O.T.S., and R. J. Reynolds Research Fellowship and by the Department of Biology at the University of North Carolina. 2) Present address: Department of Wildlife and Range Sciences, University of Florida, Gainesville, FL 32611-0304, U.S.A.74 JAMES MATHER WHITEHEAD robustus (EISENBERG, 1976), among old world cercopithecines (GAUTIER, 1969) including Cercopithecus ascanias and C. mitis (MARLER, 1973), Cer- cocebus albigena (WASER, 1975, 1976, 1977a; WASER & WASER, 1977) Papio spp. (BYRNE, 1982), among old world colobines, Colobus spp. (MARLER, 1969, 1972; OATES & TROCCO, 1983), and Presbytis entellus (RIPLEY, 1967) and among the anthropoid apes, Hylobates spp. (CARPENTER, 1940; ELLEFSON, 1968; TENAZA, 1976; MITANI (1985b, c, d), Symphalangus syn- dactylus (CHIVERS, 1974, 1976), Pan troglodytes (MARLER & HOBBETT, 1975) and Pongo pygmaeus (GALDIKAS, 1983; MITANI, 1985a; others in SEBEOK, 1977). These species normally inhabit dense forests where visual com- munication is impossible beyond short distances. In such habitats selec- tion favors auditory modes of communication, especially over long distances. The loud calls of mantled howling monkeys