Canid vocalizations

Behavloural Processes 1 (1976) 57-75 83 Elsevler Sclentlflc Publlshlng Company,

57 Amsterdam

- Printed

In The Netherlands

CANID VOCALIZATIONS

GUNTER Behalvoural (Received

TEhlBROCK Science Sectton 17 October

Humboldt

1975. revised

Cfn11vtbltat Berlm (Germarl Democratic

Republic)

26 March 1976)

ABSTRACT Tembroch,

G , 1976

Canld vocahzatlons

Behav

Processes,

1 57-75

The classlflcatlon of acoustic signs 1s related to four aspects, the phonetic, the syntactic, the semantic, and the pragmatic Canld vocallzatlons can be subdlvlded Into 10 classes, which are described The meanmg and functions are consldered ln respect to releasing functions, control functions (In the cybernetic sense) and III relation to metabohsm, reproduction and territory Examples are given of age-speclflc sounds and of sound ontogeny In addltlon, the metrics (entropies of mformatlon) are demonstrated m an example of sound sequence m the dog

INTRODUCTION

The anatomical and physlologcal bases of sound production m mammals have been a field of mtenslve research smce the nineteenth century (see Schwartzkopff, 1960, Kelemen, 1963, Tembrock, 1966) The properties of the sounds are known only for some groups, especially primates, dolphms, pmmpeds, and m respect to ultrasonic commumcatlon (Sales and Pye, 1974) Our knowledge of camd vocahzatlons is based upon older descriptions and only a few investigations with modern methods (Heydecke, 1958) The followmg matenal gves a review of some aspects of our understanding of camd vocalizations, a systematic review ~11 be gxven m a separate paper (Tembrock, In press, b) MATERIAL

AND METHODS

The followmg review 1s based upon 706 recordings of camd sounds m our phonothek Some 431 sounds were selected for special analyses In the matenal, the followmg species are represented Cartes famrllans, C exfamlllarls dingo, C e hallstroml, C lupus, C latrans, C aureus, Alopex lagopus, Vulpes vulpes, V v fulva, V corsac, Cynalopex chama, Cerdocyon thous, Chrysocyon brachyurus, Cuon alpmus, Lycaon plctus, Otocyon megalotls

For the sonographlc

analysis, the sonograph

6061-B of the Key Electnc

58

Company was used Intensltles were recorded usmg the Pegelschrelber PSG 102 of the VEB Messelectronic Dresden, for osclllographlc recordmgs the photorecorder EMG Budapest 1578/l was used CLASSIFICATION

In general, there are four aspects of sound accordmg to which sound groups can be dlstmgulshed (1) Classification by phonetlc charactenstlcs, 1 e , signal-structure (phonetlc) (2) Classlflcatlon by temporal pattern of sound sequences (syntactic) (3) Classification according to the meanmg of the sound types (semantic) (4) Classlflcatlon by functions of the sound types (pragmatic) Using tape recordmgs, we organized the most important canme sounds mto groups accordmg to then phonetic charactenstlcs These sounds were chosen from a much larger set of data in order to determine typlcal sound classes On the basis of the sonograms of numerous canme sounds, the followmg sound structures appeared very often and m many different species Thus the existence of basic types of sounds could be assumed These ten sound classes are described as follows (1) Long sounds with more than one band and with great frequency changes as well as fluctuations in amphtude The frequency bands are relatively wide, and this width increases with nsmg intensity The ascension time 1s relatively long (“whlnmg sounds”), the sounds are often broken off or repeated, with a tendency towards cycles m the repetltlon of sounds (Fig 1) (2) Long to extended sounds’, several bands to very wide bands, they lack great changes in frequency, the wide-banded phrase is maintained at full mtenslty, ascension time variable (medium to long depending on whether the wde-banded phrase is m first or second sound section), no cychc change of amplitude, little tendency to repeat (repetltlons are therefore non-regular, whlmpermg-crying sounds) (Fig 1) (3) Long to extended sounds, more than one band, long ascension time, few non-cyclic vanatlons of amplitude, frequency changes m begmnmg and end portion, increased mtenslty limits the number of frequency bands and causes lengthening of the sound, non-cyclic repetitions are found (whimper) (Fig 2) (4) Long sound, narrow-banded, usually only one (high) fundamental frequency, few non-cychc changes of frequency and amplitude, medium ascension time, a marked tendency towards cycles (bleetmg, screaming, cheeping, rmgmg cries, often combined with other sounds, especially growls) (Fig 3) (5) Extended sounds, several bands to very narrow bands, long ascension time, few vanatlons m frequency and amplitude, with longer stationary phrases and stronger alterations only at the begmnmg and end, occasionally ’ Long sounds

are defined

as havmg

a duration

of 0 5-l

0 s, extended

sounds

> 1 0

s

59

Fig 1 Sound classes (1) left and (2) rrght Vulpes cot-sac ti, whlmpermg the male, 4lopex lagopus ti, whlmpermg In agorustIc behavlour agamst

(1 ), m contact with Vulpes oulpes (2)

Fig 2 Sound class (3) (a) Lycaon pwlus C, whlmpermg In social contact,(b) brachyurus 6, whlmpermg sound In social contact with man

Chrysocyon

“frequency Jumps” m the middle section, increase m intensity IS connected with the length of the sound, there is a tendency towards repetition (howling) (Fig 4) (6) Short sounds; wide-banded, short to mednun ascension tune, amphtude mcreases and decreases only once, nse in mtenslty leads to longer sounds and to the appearance of a prunary frequency with more bands, a marked tendency towards repetition with various cychc sequences (barkmg) (Flg.5, 7B).

60

ti-

---

L,

-:

-1

I

I

I

I

1

I

I

b------c_

-

-

, whlmperrng

111social contact (c) Doberman, whlmpermg,

Fig 3 Sound class (1) (a) L\‘caorz PIC~UL Canrs exfamlllarla hallstromr :, whlmperrng, whlmperlng

- “.

I

I

1-I

1

-x4-*-.

*--

__

-

with man, (b) (d) Carps lupu\,

--

-0

_

-7

-c-_

---

. I

L

L

Fig 4 Sound lndlvldual

class

(5)

r

(a) Canis

I -

latrans,

I

13

1-l

howling.(b)

_-

Cams

1otran.s howling,

__

another

61

14

18

5

Fig 5 Sound class (6) (a) Canrs aureus C,, barklng agamst the male, (b) Alopex lagopus d , barklng against man,(c) Dusxyon cmereoorgentatus d , barkmg agamst man, (d) Chrysocyon brachyurus 3, a barklng sound of the barkmg sequence

(7) Extended sounds, wide-banded, long ascension time, changes m amplitude wth tendency to form cycles, appearance of more bands, pnmary frequency with increase m mtenslty (growl, snarl, hiss) (Fig 6) (8) Short sounds, mde-banded, extremely short nse and decreasmg time on amplitude, a marked tendency to repeat; sound lengthened to “long sounds” at high mtenslty and the tendency to repeat 1s then lessened (snorts, panting, yelping sounds) (Fig 7A, B) (9) Short sounds, hmlted to lower spectrum of frequency but wide-banded, medium ascension time, only one change m amplitude, repeated m cychc form (whlmpermg-“growl”) (Fig 8) (10) Short sounds; wide-banded with medium ascension time and charactenstics of No 6 but repeated, a stanza with a specific number of sounds (barkmg sequence) (Flg.9). MEANING

AND

FUNCTIONS

OF THE

SOUNDS

In older matenal, and also partly m more recent papers, the sounds of the Camdae are for the most part described by their meanmg and functions The orgamzatlon 1s based, therefore, extensively on emplncal, psycholo@cal descnptions (“rage ” , “fear”, etc ) and does not take into account the recent works on the mechamcs of behavlour (see Marler and Hamllton, 1966) Vocahzmg behavlour can be (a) Tnggered by external events

punos

8ulqJeq

aql uaawaq

(uollecuao~ul

sadpo JO

sadp,l

lalawemzd)

JO punos a3uaJaJJlp

%uldlaS aql pue (Ual) (edmmd aqk 8~ 81~ I

_

I

snduii’q 1ado/p (a)‘sn]Xd

UOVJ4c7

(e) ‘IxaJuoa

(p)‘JVS.x7J

(aarsuaJap)

(,,ay

UI

(3,

sadp,l

atlswoile

‘StlJlnD

a~,,)

8UlIMOJtd

SlUD~

spunos

‘snoyl

1!0~3?v?fl

(q)‘SnlVlIrJ%rVoJ~JulJ

%uldlaA

(8) sse13 punos

u~LJO~JJ,]

(L)

STq3

vi

punos

BIJ

9 i]lJ

63

Fig 8 Sound class (9) Rhythmic whlmperlng-growl In social contact (from left ro right)) (a) Cynalopex (b) Canrs erfamdrarrs hallstrorw n, (c) Nvctereutes female, (d) Cams aureus _

sequence

(“Muffen”

= “yum-yum”)

chama 3, In contact with the female, procyonodes d, In contact with the

(b) Controlled by the Internal state Behavlour triggered by external events IS evoked by circumstances m the environment and a correspondmg releaser-effect m the sense of Wilson and Bossert, 1963 Controlled behavlour 1s built up of primer effects, the organism develops an appetltlve behavlour towards adequate environmental condltlons. The primer effects determine the status of the organism The followmg internal states - motlvatlons, emotions, vlglance - affect this considerably Motlvatlons determine the function-speclhc behavloural patterns (for example, the search for food, the search for reproductive partners, and the ensuing behavlour patterns) Emotions establish the intensity of appetites and aversions Vlglance defines the state of arousal which underlies regular dally and seasonal patterns. Vlglance establishes also the general need for information which is manifested m exploratory behavlour.

(a) Vocallzatlon

behavrour triggered by external events

The most common form of this behavlour IS observed when the anunal tries to overcome disturbances, generally through defensive behavlour The sound forms developed in this context have denved from an (explosive) expiration which can be followed by an audible mspu-atlon They are con-

Fig 9 Sound class (10) (a) ‘I-ulpes corsac 6, barking lagopua d , barking sequence

sequence

(“Bellstrophe”).

(b) 4lope~

netted with a higher motor development, mostly with a “wide-banded” pattern, thus correspondmg to a behavloural model encompassmg many elements The sounds themselves are also wide-banded and therefore contain little mformatlon, and so are effective outside the bounds of the species They are “explosive sounds” with mmlmal ascension times and high amplitudes, both of which mhlblt adaptation by receivers They last a short time and can be repeated If circumstances remam unchanged They are sounds of class (8) according to our classlhcatlon, mostly sounds described as yelps The short forced-out breathmg sounds belong here too (pant)

65

Sounds of defensive behavlour m mammals were examined by Tembrock (1966), and m this paper some camd examples were also considered Contact between conspeclflcs leads to the yelp as a means of defence, especially in the Vulpes species If there IS a dominance-subdommance relationship, a whine element 1s mlxed m In this case the sounds of the subdominant mdlvldual sound clearly “higher” This IS an addItIona demonstration of status m which the two types of vocahzatlon behavlour are combmed (the spontaneous and the tnggered) In this situation the posltlon of the ears shows the status A fox, encountering another species, shows a defensive behavlour with erected ears and pushing forward, with a simultaneous explosive defensive sound This sound form has a releaser-effect on the receiver It has the function of Increasing the latter’s distance Another group of noisy, boisterous sound forms (from which the defensive sounds may be derived)) 1s our class (7) These sounds are also trlggered vocahzatlon behavlour They are known as spitting, growling, hlssmg, and they are usually extended sounds They show a noisy (but not faster) breathmg and can also be heard on msplratlon These sounds are functional “warning” signals, they serve to change the status of the receiver, m this respect they lmtlate a primer effect In the Camdae these sounds appear with many dlfferent variations, the most frequent being the growl In many cases other sounds are mlxed m, as for example, barking, crymg, yelping An increase m stlmulatlon by the alarmmg circumstances which cause growlmg leads to faster breathmg and thus to mcreasmg disruption These sounds can be shortened as the pauses between them are lengthened At the same time, an Increase m amphtude appears (shorter and louder) Barkmg belongs functionally to this group (6) It is released by circumstances which excite the ammal and affect the emotional state In this way the number of repetltlons correlates with the degree of excitement Barkmg 1s pnmanly a warnmg for other members of the species, particularly the young It IS uttered at low Intensity with a closed mouth and IS often combined with a growl As intensity Increases it 1s uttered with an open mouth and an increase m the amount of mformatlon contained 1s accomplished through the appearance of dommatmg frequency bands Barking m a sltuatlon which also causes agomstlc behavlour can beg-m with a harsh introduction and 1s then close to sound type (8), the explosive sound, which it resembles phonetically (Fig 10) Generally it can be said that the triggered sound forms are defensive, warnmg, or excited sounds (alarm sounds), they have a mde-banded frequency spectrum and show a close relatlonshlp to “noisy breathmg” The loud high whistle tone must also be considered m this connection It 1s a sound occumng m situations wlthout sufficient mforrnatlon for the animal and which thus release uncertainty It is a call of reduced intensity makmg its way through narrow upper ar passages The sound like “khn” has the character of panting

-

FIN 10 Barking with whlmperlng

(6) Con trolled

sounds In agonlstlc context components (type 1 and

acoustic

2)

From left to right lncreablng Intensit> , mlxed \‘ulpc< ~wlpeb ’ (against another male)

behaaiour

The functmns of this behavlour Ile in the carry-over of InformatIon, such that the utterances themselves represent the regulations This presents a system-speclflc behavloural programmlng which. above all, defines the motevatlon level through status One can differentlate between three groups here Vocallzatlon behaiqour relatmg to metabolism Vocallzatlon behavlour relating to reproduction Vocallzatlon behavlour relating to maintenance of orientation in space and time, lncludlng the social system Vocalfzatlon

behactlour

relating

sound uttered m huntmg prey those which maintain contact appear mostly in thl:, context (excitement, alarm 1, but then sounds

to rnetabollsm This category Includes the and those which agtate the prey as well as urlthm the huntmg group Barking sounds \then ongmally emltted as a reaction to prey affectmg the latter so that they become huntmg

\‘ocallzatzon behaclour relating to reproduction \Ve must dlstmgulsh here between two functional systems (a) Palnng behavlour (and beha\rlour of the pair) (b) Ralslng the 4 oung (nursing behavlour) In this realm the canld vocalizations are the most diverse The informational content of the sounds IS Increased by the followmg parameters Decrease of the width of the frequency bands to one or a fe\f bands

67

Regular changes m frequencies Regular changes m amplitude Regular temporal patterns m the changes Formation of cycles Development of classes of sound durations Sequences mcludmg different sound elements The whlmpermg sounds (sound classes l-4) form a group of this type The greatest mformatlon content IS found m (3) and (4) In the palnng behavlour of the Camdae three functions must be dlstmgulshed (1) Partner selectlon Behavlour and vocallzatlons of the female contam strong agomstlc (aggressive and defensive) components, by which the weak partner IS rejected and only the strongest (In respect to the constitution of the females) can succeed We found m Vdpes vulpes that a male which was exhausted because of a fight with a nval, could no longer offer resistance to the symbolic agomstlc behavlour of his female and had to flee from her The most common sounds of the female under these circumstances are the growlbark, yelp, snarl and snarhng cry to scream (sound class 2) The male reacts to these sounds only with sound types (A), (9) and (10) (2) Rivals’ behavlour Behavlour dlrected towards a member of the same sex appears mostly between males only This behavlour has always an agomstic character and stretches from strictly ntuahzed contact to actual fights The vocallzatlons appear, above all, In phases of “threat” The VuIpes’ threatenlng calls are whlmpenng sounds which rise m mtenslty hke the noise of slrens (sound type 3) In other Canldae, threats are of the snarhng type but are In all cases extended sounds During contact with the rival wlthout aggresslon the sounds are short, ekploslve and often repeated (for example, shows of strength without actual blttng and flghtmg, 1 e agonlstlc display), often m combmatlon with sound type (8) Carols species execute In this context an audible chckmg of the teeth as a ntuahzed threat (3) Pair behavlour This behavlour serves to mamtam the pair Li’hlle the partners are m close proxlmlty, a growl (type 9) and a rhythmic whine (4) are uttered Often both are combmed, so that the growl sound Is preceded by a whlmpermg (see Fig 8) In this case the rhythm of the sound sequence IS obviously of Importance This rhythm shows also the barkmg sequence, which can hold the pair together over greater distances, or else bnng the pair back together The phonic element of the barkmg sounds IS brought out here m a new context and has, as a barkmg sequence, the function of decreasmg the distance between emitter and receiver The howhng or bark-howhng of the Canls types functions aa a barklng sequence In close proxlmlty there appears a further rhythmic whlmpenng (type 3) which clearly shows elements of early ontogeny It 1s “mfantlle” and thus represents a “phonic regresslon” Basically the same sound forms as those appearing m palnng behavlour are mvolved m caring and nursmg behavlour Thus, here agaln we fmd a rhythmic

68

whlmpermg, growl, and growl-whlmpenng Only the barking sequence IS absent Other elements of commumcatlon belong to the carmg system, e g the sounds of the young They are uttered under circumstances m which a certam behavlour of the adult is demanded, above all, m bodily dlscomfarts such as cold, dampness and hunger The sounds of the young include then the same basic elements which the adult Camdae use There IS the rhythmic sequence of whmmg to barkmg sounds (it 1s possible that they contain ultrasome components) The sounds include mdlvldual components, but there IS, however, no defmlte mformatlon as to whether the young can be recognized as mdlvlduals by their voices Ultimately the domlnatlng control IS always olfactory The cries of pan of the young (type 4) are very strong behavlour releasers for the adult Canldae The latter not only call but also react very aggressively at the same time towards all ObJects in the area surrounding the young The bark as a warnmg by older animals quiets the young Immediately and usually causes flight Into the burrow We also ehclted this reactlon with young foxes which as Isolated animals had never before heard an adult bark

I’ocaluatlon behavrour relating to the mamtenance ot orlentatlon m space and t/me, mcludmg the social system In close proxlmlty (where there IS permanent commumcatlon) the sounds with releaser effects regulate distances on meeting such that there 1s always an mdlcatlon of status mlxed m (domenance-subdommance) Subdominant mdlvlduals combine the sounds with high (mfantllel frequencies, I e , whmmg elements, so that the voice becomes “higher” A very high pure whlmpermg from sound class (3) can show a subdommant status but IS then combmed with an accompanying pattern of tnovements (crmgmg, tall tucked between legs m Cams. vlslble laymg back of ears m 17ulpes and a 11lder opening of the 11~s) The Cams howlmg (= cry) (type 5) 1s a special case It can be uttered occasionally by an isolated ammal, then It relates to the mamtenance of the pair sltuatlon Young and Goldman (1944) named It the “lonehnes~ cry”, Elsfeld (1966) and Zlmen (1971) the “separatlon cry” The other fortn in typical social contact IS the “choir of cries” (Tembrock, 1959a, Elsfeld, 1966, Zimen, 1971) The chorus IS described by Zlmeti as follows ‘The ammals run together, the young animals bunch themselves close1 together, the older annnals mamtam distances between themselves Direct social contact occurs more often than not Not all the ammals howl along w.zlth the others all the time The u hole process m Canls lupus creates an nnpresslon of a “pack ceremony” ’ .A “cry concert” lasts about 20 seconds, maxmlum 2 mmutes Theberge and F,alls (1967) sho\ied that lsolatlon brings forth an increase m howlmg or crying The same authors consider the cry to be an Important component of the coordlnatlon of the social actlvltles of wolves They consldered It for the first time as “long distance” communlcatlon, important for social unit> whose members are often separated, as in hunting behablour The baking sounds could also mamtam contact Kuhme (1965) mentlonecl this also with reference

69

to Lycaon The animals emit a clear bark when they are followmg gazelles on a hunt Chorus crying could also serve as an advertisement of territory for groups and thus Influence the density dispersion of populations AGE-SPECIFICSOUNDSANDSOUNDONTOGENY

In general sound ontogeny can be considered in two ways (1) Defu-ntlon of age-speclflc sounds wth a definite commurucatlve function related to a special penod dunng development (2) Defmltlon of the maturity of sound forms which still have a communicative function at matunty Both aspects can overlap, since there can be sounds which have definite functions during maturation, but which do not correspond to those at the adult stage In this case they will show distinct deviations, thus, they will develop special characteristics of the sound type whose primary ontogenetic level they represent We would like to name this process “progressive ntuahzation”, i e , ‘antlclpatlon’ of developmental levels whlc h mantam signal functions through this antlclpation As had been known for a long time, there can also be a “regressive ntuahzatlon” (often simply called regression) Here infantlle sound forms become signals in ntuahzed form directed towards adults, this process IS especially well-known m reproductive behavlour but also m agomstlc contexts, m which the ritualized InfantlIe sounds are effective as aggresslon inhibitors In order to understand the Important charactenstlcs of sound ontogeny, one should keep the following points m mind (see Tembrock, 1959b) (1) Are there particular sound forms durmg development which do not occur m the adult animal in this form3 (2) When can the adult sound forms first be ldentlfled m ontogeny and which structural changes occur durmg maturation7 (3) Are there general prmclples of sound change In ontogeny and to which charactenstlcs are they related? (4) Are there defmlte norms for sound lengths and intervals between sounds which are emitted as sequences7 (5) Do definite temporal patterns appear m the vocahzatlon? (6) On which prmclples are sound classes formed? (7) Are there mterdependencles between the single sound types (syntactic aspect)? (8) What correlations exist between the sound forms and any particular sltuatlon (pragmatic aspect)? (9) Under what circumstances are certain sounds released? (10) Are there defmite receivers for the sounds? (11) What meaning do sounds carry for the receiver (semantic aspect)? (12) Is there a connection between mformatlonal content (metric aspect) and age7

The sound development of the maturation processes of organs (see Fox, 1964) IS of particular importance We have investigated some areas of sound development m the domestic dog which allow yuantltatlve and qualltatlve depictIon of sound dlfferentlatlon m the first months of life (Leschke, 1968) For \‘nlpes wipes there are very thorough ontogenetlc reports available (Tembrock, 1957,1958,1959c) Releasmg stlmuh are, externally, dlsturbmg sizes and, internally, hodtly Imbalances (low body temperature, hunger, thlrstl and also a lack of contact with snnllar coats On strong external stlmulatlon of the above species, the squallmg can be altered through a certain tonatlon There 1s a tendency to shorten the sounds so that sequences are formed which can show a stressed end sound Along with this long sounds remam from the 8th day (up to about the 23th day) which appear in a “tremulous” varlatlon (Fig 11X) From the 18th day onwards a rhythmic sequence 1s formed from this variation The sequence 1s a forerunner of the true barking sequence which can be heard from the 21st day onwards Fig 11B shows this development The sonogram shows the begmnlng of the whme on the 26th day, after the barking sequence This can be consldered as a regressive element for adult foses which utter barkmg sequences which are not at full Intensity (Tembrock, 1960) In addition this development sequence allows clear recognltlon of the “change of voice”, eight-week-old foxes already show the typical frequent] component of the adult fox A bark appears for the first time, too, as a phonetic element on the 19th day, the forerunner of this appears to be the stressed end sound uttered on the 9th day Pure whmlng sounds were heard first on the 26th day, but there iieere previously squalling sounds which are marked by dommatlon of high frequency The development of rhythmic sound structures came about quite naturally The appearance of certain faboured mtervals between vocahzatlons 1s a self-ecqdent prlnclple and these Intervals can appear \tlth several sound folms Thus, on approklmately the 25th day, a gronllng sound appeared with almost the same rhythm as the barking sequence - a throaty sound with a maulmum frequency between 200 and 300 Hz This sound 1s heard in two forms \\lth adult foxes one which presents the approslmate barking sequence, the other, which is uttered only durmg mating. depicts a somewhat faster sequence, which almost corresponcls to the “tremolo” (as forerunner of the barking rhythm) The adult fox can also utter these earlier forms during those times of the year when maturation cycles occur, and sometimes one heals the whole series tremolo-whine, growl-whme. gro\\l, and fmally the barking sequence Fig 12 shows a sonogram of L_vcaorz pxt~s pups at the age of 6 da>s Here again the tendency towalds repetition of shortened sounds 1s recognizable These sounds become occaslonally blsyllablc such that the sound syllable presents a clear drop m the pitch I._~caorz mamtaln the tremolo element even as adults Pups’ sounds which ale caused by physlolog~cal disturbance> as well as bl grooming behavlour by the mother (or parents) have an ambivalent character

Fig 11 The ontogenesls of the barklng sequence of I u/pea ~~lpes (rune days old),(B) thirteen days old (a), twentyslx days old (b)

(A) “tremolo-whrmperlng”

they are sometlmes aversive (towards the stlmulatmg circumstances) and other times show appetence or care-sollcltmg charactenstlcs (which call the adult to them) In particular the mten.sltJ , ascension time (tendency to shorten) of sounds, and the frequency (wide spectrum) are related m the aversive vocallzatlons Characterlstlcally, care-sohcltmg sounds have a content hmlted by a temporal pattern and a shapmg of the frequency pattern with dommatlng frequencies and probably also with a temporal extension of the sounds Threats present aversive components which lead to the yelpmg sound type b] the 4th week At this time It IS used by the pups m fights and serves to Increase distances Such “challenges” mature to become typical defensive sounds of the adult foxes Barks retain an ambivalence with Canldae m the barking

Fig 12 Whlmperlng sounds, Lycaou

prc tits. SIY days old

sequence a rhythmic ordenng of the afflnltlve component3 is strengthened Koenig (1970) described the sound ontogeny of Fcnrzecz~s zercfa 1st da] Clear, lengthened rlsmg and fading, lightly snarling whimper very often audible Whimper more Infrequently than before 3rd da) 5th da] Ii’hn-nper and squeak on tactlle stlmulatlon or dlsturbance (taken out of nest) on being taken out of nest TempoAll 8th day Loud howl (unpleasant) slmllar to bark In nest with mother. seldom any vocallzatlons 17th day Soft answer to greetings of mother 18th day Shrill yelp and bark on hemg taken out of nest Screaming cry on greater disturbance 21st day cry as call of being left behmd (young animal) 26th day Screaming The screaming cry corresponds to the barking sequence (1U) Altmann and Reeker (1971) recorded growl sounds for \‘~c/pcs co~bac the first were heard on the 23rd day, on the 25th day a Hess (defence agamst bltlng) appeared, on the 30th day m the sltuatlon a yelp was audible Barkmg was heard first on the 24th day, whlnlng of pain on the 29th day METRIC ASPECTS OF SOUND COhlhIUNICATJON

OF C ANID AE

In an lnvestlgatlon of stochastic and rhythmic charactenstlcs of the domestlc clog, Hirsch (1972) has explored the questlon of whether one can prove a ( orrelation between the content and the function of the bark through the use ot mformatlon theory To do this, barking sounds were subdlvlded mto classes according to length, and Intervals between the single sounds of the sequence were metrlcally recolded As function relation test, agonlstlc behavlour and play behavlour wele examined

In summary of his fmdmgs, the behavlour m agomstlc context indicates a smaller alphabet - the pathway between sender and receiver IS short m the middle and the probability of the appearance of what he terms u-relevance entropy 1s low Three types of sounds can be dlstmgulshed (1) Senes with many sound length vanatlons and thus greater mformatlon (2 85 bit/symbols and 4 54 bit/s) and mth relatively constant intervals and, with these, less mformatlon (2 81 bltlsymbols and 3 192 bit/s) (2) Series with relatively constant sound length (2 32 bit/symbols and 4 25 bit/s) and greater interval devlatlons (2 58 bit/symbols and 4 35 bit/s) (3) Series with great sound length devlatlons (3 00 bit/symbols and 4 06 bit/s) and great interval deviations (3 32 bltlsymbols and 4 82 bit/s) Through these variations, adaptations by the receiver are mhlblted or at least hmlted In general, the connection of mformatlon and symbols is great with agonlstlc behavlour From the evidence it might be assumed that here the source of coding 1s motivation system Play behavlour, however, seems to stem from different sources, as the material IS very heterogeneous The sound lengths show relatively httle mformation (average 3 20 bltlsymbols and 2 96 bit/s) In comparison, the average values for agomstlc behavlour are 2 635 bit/symbols and -2 28 bit/s for the sound lengths and 2 9 bit/symbols and 4 36 bit/s for the intervals Play behavlour employs a longer alphabet Given the actual mformatlon values there 1s then a decrease with time such that 80% of the ongmal mformatlon can be accepted as a crltlcal threshold, If it falls short, the barking sequence IS broken off In agonlstlc behavlour hlarkoff chains of the order of 2-5 appear, the higher components of the order appeanng more infrequently Play behavlour elhlblts hlarkoff chans of the order of 3-7 In general it can be deduced that play behavlour makes use of phonic redundancy in particular, this venfles Tembrock’s supposltlon that generally in this context motor redundancies are employed Agonlstlc behavlour makes use of acoustic Information CONCLUSIONS

Ecolo@cal factors and the pnmanly nocturnal actlvlty of the mammals have led to the evolution of a very highly differentiated audltory system Frequency IS an important mformatlonal parameter, the perlodlc frequency (that 1s the frequency interval between the harmonics) 1s correlated with the internal state (motlvatlonal-affectlve state) of the emitter For social relatlonships, the mdlcatlon of the mdlvldual state 1s very Important The regulation of distance between synlocated animals establishes a dynamic system In time and space (“Raum-Zelt-System”), determmed by the actual appetites and averslons It seems to be possible to dlstmgulsh some general classes of condotlons in the ecolo@cal and social surroundmgs of an animal, correlated with general classes of sounds In higher mammals, modulated and/or mixed sounds

ennch the posslblllty of multi-scahng lnformatlonal transmlsslon, especially m respect of emotional states Besldes the phonetic propertles of the sounds, syntactic structures and rules are very Important as parameters of mformatlon They lead to a formatlon of syntagmata with respect to special rules of Information Segments wlthm the sounds may also contnbute to the enrichment of information The sound sequences of Cants (barkmg) show different values of information entropies with respect to the behavloural contest Sound sequences are typlcal m Camdae We have found a general correlation between the mean value of Intervals and the phonetlc properties of the sounds (Tembrock, m press, a) Changes m the sound class are generally correlated with changes m the (mean) length of the intervals between the sounds of a sequence \Ve found in a male of \‘Lllpes vulpes three types of sounds m agomstlc behavlour (in one sequence) 8 6j20 s Explosive barking cry 100 s Barklng cry 60 s 3 7120 s 2 5120 S Barking 10 5 This demonstrates a decreasing intensity, high Intensity IS correlated with a special sound type, short intervals and longer duration of the sound utterance than low mtenslty (barklng) Under other circumstances, the same male utters only barking sounds of about 260 seconds with a mean value of 2 6 sounds In 20 seconds That mdlcates a colt-elation between sound class and duration of intervals In general, phonetic. syntactic, and metric (entropies of mformatlon) properties of csnld sounds are correlated with speclhc behavloural states

RFFERENCES Xltmann, D and Reeker, \i’ 1971 Ve~halten,anaI>se der Ontogenese ion Steppenfuchsen, \ ltlpeb cotaar L Zoo1 Gait N F, 41 l-6 Elsleld, D , 1966 Verhaltensbeobachtungen an elnlgen Wlldcanlden Zeltschr WI\S Zoo1 174 22G-289 Fox RI W , 1964 The ontogeny ot behavlour and neurologlc rePpon\es In the dog L\nlm Behav, 12 301-310

,

Heydeche, R , 1958 Verglewhende Untersuchungen zur Lnutgebung der Canlden Thesis, Humboldt-Umv , Berhn, 72 pp Hllsch I 1972 hletrlsche Analyse der Bellsequenzen des Hau.hundes Thesis. Humboldt UnlI Iierlln. 114 pp Kelemen, G , 1963 Comparative anatom> and performance ot the vocal organ In vertebrate< In R G Busnel (EdItor) Acoustrc Behawour of Animals Elsevler Amsterdam. pp 4b9-521 Koemg L , 1970 Zur Fortptlanzung und Jugendentwwhlung des Wu,tenfuchses I FcrtrtccLO rocfu Zlmm li80) Z Tlerpsbchol 27 X.5-246 Kuhme, ii’ D , 1965 Freilandstudlen zur Sozlologie des Hynnenhundes (.L.\caorl NIL hcI~rprnus Thom,ls 1902) Z Tlerpsychol . 21 495-541 Leschke, hl 196s Eerlin. 85 pp hlarler. P and Nem York,

Lautentwwhlung

HamIlton. 771 pp

W

1966

beI Schaferhund-Welpen hlechanlama

ot Animal

These> Behalqor

Humboldt John

Wile\

L’nlv & Sons,

75

Sales,

C

and

Pye,

D

, 1974

UltrasonIc

Commumcatlon

by Animals

Chapman

and

Hall,

London, 281 pp Schwartzkopff, J , 1960 Verglelchende Physlologle des Gehors Fortschr Zoo1 , 12 20fi264 Tembrock, G , 1957 Zur Ethologle des Rotfuchses (\Llpes uulpes (L )). unter besonderer Beruckslchtlgung der Fortpflanzung Zoo1 Cart N F , 23 289-532 Tembrock, G , 1958 Lautentwlcklung helm Fuchs - slchtbar gemacht Umsch Naturwlss pp 566-568 Tembrock, G , 1959a Stlmmhche Verstandlgung unter Tieren. eln Forschungsproblem der Blo-4kustrk WISS Fortschr ,9 302-306 Tembrock, G , 1959b Tlerstlmmen Elne Elnfuhrung m die Bloakustlk Zlemsen, Wltten berg, 285 pp Die neue Brehm-Bucherel 250 Tembrock, G , 1959c Zur Entwlcklung rhythmlscher Lautformen beI vulpes Verh Deutsch Zool Ges (Frankfurt/M , 1958), In Zool Anz , Suppl 22 194-202 Tembrock, G , 1960 Spezlfisches Lautformen helm Rotfuchs (Vulpes Ldpes) und Ihre Bezlehungen zum Verhalten Saugetlerkdl hlltt , 8 150-l 54 Tembrock, G Experlentla, Tembrock, G Leopold

, 1966 ,

Die physlologlschen 22 561-572 (In press, a) Zeltmuster

Tembrock, G , (In press, Theberge, J B and Falls, Am Zool ,7 331-338

b) J

Grundlagen In der akustlschen

Die Lautgebung Howling

, 1967

der

Lautausserungen Kommumkatlon

bei Tleren Nova

der Camden Eme verglelchende Untersuchung as a means of communlcatlon In Timber wolves

Wilson, E 0 and Bossert, W H , 1963 Chemical communication among animals Prog Horm Res, 19 673-716 Young, C, and Goldman, E , 1944 The Wolves of North America New York Zlmen, E , 1971 Wolfe und Konlgspudel Verglelchende Verhaltensheobachtungen R

Piper

& Co,

hlunchen,

257

Acta

Recent

pp

KURZFASSUNG Tembrock, 57-75

G , 1976 Akustlschen (III Engllsch)

Kommunlkatlon

beI Canlden

Brho~l

Processes

1

Die Klasslflkatlon von Lauten als akustlsche Slgnale geht von vier Pramlssen au. dem phonetlschen. dem syntaktlschen, dem semantlschen und dem pragmatlschen Aspect Fur die Canlden werden 10 Lautklassen aufgestellt und durch phonetlsche Elgenschaften gekennzelchnet Bedeutung und Funktlon dleser Laute werden unter folgenden Geslchtspunkten abgehandelt Auslosung, Steuerung und Regelung, Stoffwechsel. Fortpflanzung Errlchtung und Erhaltung \on Terrltorlen Ferner wlrd das Problem der Laut-Ontogenese erortert und an Belsplelen belegt Schllessllch werden Hlnwelse auf metrlsche Xspekte der akustlschen Kommumkatlon beI Canlden gegeben (Informatlonsmasse)

Tech

,