Behavior of Varanus Griseus During Encounters with Conspecifics

1997 Asiatic Herpetological Research Vol. 7, pp. 108-130

Behavior of Varanus griseus during Encounters with Conspecif ics

ALEXEY YU.TSELLARIUS AND ELENA YU.TSELLARIUS

Program VARAN, Dept. Herpetology, Zoological Institute. 199034. St. Petersburg. Russia

- of Abstract. In 1990-1993 in the western region of the deserts of Kyzylkum (Uzbekistan), constant observations of various a group of desert monitors in natural conditions were conducted. Described are manifestations emotional states of monitors, and common types of monitor interaction. Given are detailed descriptions of the course of contacts between the animals, illustrated by photographs. Fights were rarely noted and only between of and not from a unfamiliar lizards. It is proposed that ritual combat arises from displays dominance is varied and not Data ntualization of the fight. The behavior of monitors during contacts highly stereotypical. from observations attests to the existence of a complex, mammal-like social structure in the population. Considered are probable mechanisms of intraspecific communication of monitor lizards.

Key words: social behavior, social relations. Reptilia. Sauria, Varanus griseus

Introduction Behavior of animals during intraspecific contacts is usually considered as a succession of behavioral acts, In the article at hand we have made an to attempt but not as a social interaction directed at the mainte- reveal the communicational function of common nance of long-term interrelations within a socium. behavioral acts of desert monitor. We have made also The analysis of behavior is reduced to statistical anal- an attempt to describe some types of interactions ysis of the sequence of the behavioral acts of contac- between monitors and the role of these interactions in tants. Generally, the task of the analysis is limited to social organization of population. We will not touch discovery of the most probable response of a lizard to behavior connected with courtship and mating upon the acts of another lizard. In analysis one seldom in the article. present allows for the circumstances, under which the interac- for the of endan- In 1989. when a program study tion took place. The history of interrelations of con- gered species of reptiles was developed by us, the tactants, as a rule, is not taken into account at all. principal emphasis was put upon their ecology. Actually, the social interaction is considered as a behavior of When we stumbled onto the fact, that the closed system with internal self-regulation, indepen- the monitor lizard is much more complex than was dent of the structure of the socium. imagined, we no longer had the opportunity to alter Viability of the population (the ability for bal- the program of study. Hence, the gathering of etio- anced reproduction in particular) is to a considerable material had to be conducted at the same time logical extent determined by its social structure. The social as the primary tasks. Although we are aware of the structure of many species is rather impressed by envi- of our data and the necessarily sche- incompleteness ronmental conditions and the reptiles are not an matic and fragmentary nature of our description, we exception (Panov, Zykova, 1985; Poly nova, Panyush- do not consider its publication to be in vain. This kin 1982; Polynova, 1990; Stamps; 1977). A social issue has not only theoretical but practical signifi- response of population to environmental changes is cance since desert monitor populations arouse serious often species-specific (Polynova, 1990) and is not apprehension in many regions of Middle Asia necessarily adaptive (Plyusnin, 1990). Peculiarities of (Darevsky,Orlov 1988. Khodzhaev 1989) response of socium to the external influences are to the ele- There exists a vast literature dedicated determined for the most part by two closely interde- lizards the of mentary behavioral acts of (see survey pendent, species-specific systems of animal activity: behavior of some Carpenter. Ferguson 1977). The a) a production of the signals which carry information species of monitor lizards has also been described in about the animal and its circumstances; b) a percep- some detail (Auffenberg 1981a; 1981b: 1983: 1988; tion, processing and analysis of these signals in con- Carter; 1990; Davis et al. 1986; Deraniyagala 1958; junction with others external and internal irritants. But Gaulke 1989; Horn et al. 1994; Mertens: 1946). The principles of organization of these processes may in the most of herpetological papers the social motives be termed as a "language" and a "mentality" of a spe- and purposes of behavioral acts are not examined. cies. This issue is closely linked to the problem of 1997 Asiatic Herpetological Research Vol. 7, p. 109

management of populations and demands careful monitor lizard was specially caught, usually in the study. morning hours. In the evening of that same day we attempted to establish from tracks the site where The of Studies Region another monitor would spend the night. At dusk we The studies were conducted in the western area of the released the monitor captured earlier into a nearby sand deserts of Kyzylkum. Uzbekistan. The coordi- burrow. In the morning, as the monitors emerged nates of our permanent camp were 40° 40' N and 62° from their overnight shelters, encounter was inevita- 08' E. The landscape in this region is typical of the ble. It was only possible to perform these operations -- Kyzylkum sandy ridges, bushy undergrowths from time to time so as not to disturb the lizards and the (mainly Haloxylon persiewn, and Calligonum sp.), disrupt normal course of their lives. In some and sparse grass (Care.x physodes predominates) (Fig. instances discussed in this article, data from tracking

1 ). In the region of studies there is a rather high abun- was also used when it was possible to precisely and dance of rodents, for the most part Rhombomys opi- fully reconstruct the course of events from the tracks. mus and Spermophylopsis leptodactylus. Both During observations from hiding, detailed steno- inhabited and abandoned colonies of Rh. opiums — graphic notes were taken which were deciphered with their complex system of underground passages immediately after observations were concluded. and location not farther than 150-200 meters from one Some of the encounters were photographed (from 5 to -- another serve the monitors as refuges and hunting 16 frames per encounter). Unfortunately, a lack of grounds. means prevented us from employing photographic documentation to the extent that was necessary. In all. Materials and Methods we observed 37 instances of contact between males, 8 instances of contact between females, and 21 Observations were conducted from 1990 to 1993 for instances of contact between the sexes. periods of four to seven months annually. In all, observations were made for a duration of more than Results 20 months. In the beginning of April, the period in which monitor lizards come out of hibernation, they The Spatial Structure of the Population and were measured, marked, and caught, weighed, Annual of - Dynamics Activity released at the site of their capture usually in the Data pertaining to the spatial structure of the popula- course of a few hours after being caught. A special tion is currently being readied for publication in a sep- mark permitted us to identify the animals by their arate article. Here, however, it is only necessary to tracks (Tsellarius and Cherlin, 1991 ). Henceforth, for address a few words to this issue. The number of the greater part of the season of monitor lizard activity monitor lizards in the of studies consisted on we conducted continuous observations of the animals region — the average of four adult individuals per square kilo- following their tracks and observing them visually meter. The monitors were, however, distributed over from camouflaged holes situated in the places where the space unevenly: areas of high concentration alter- the appearance of monitors was most probable. In nating with thinly populated areas. Areas in which order to determine age, we amputated the last phalanx populations were more densely concentrated (settle- from one of the fingers of a number of the monitor liz- ments) measure nearly 100-150 hectares. The dis- ards. The specimen was processed by E M. Smirina tance between the centers of neighboring settlements (Moscow) to whom we owe our sincere gratitude. ranges from 3-5 kilometers. Each settlement is The region of operations was regularly inspected and formed from a group of adult settled individuals con- all points at which a tracks of the marked animals was sisting of five to six males of various ages and three to apparent were plotted on a chart. As a result, we have four females. In each of two settlements which were at our disposal data on age, the location of home under constant surveillance, only one female took ranges, and the nature of the interrelations between part in reproduction. The rest of the females were not the majority of the mature individuals settled in the impregnated over the entire period of observations region of operations. although they were in fact courted by the males. The Indirect exchange of information predominates in home ranges of all of the animals in a settlement the population (Tsellarius and Men'shikov, 1994). almost fully overlap each other. In the sparsely settled The monitor lizards comparatively rarely enter into areas between settlements, home ranges may, to a direct contacts. A possibility of observations of con- varying degree, either overlap or be located at certain tacts is all the more rare. Therefore, in order to gather distance from one another. The home ranges of set- sufficient data, we provoked contacts. To this end. the Asiatic Research 1997 Vol. 7, p. 110 Herpetological

is in motion. When the monitor examines tied animals range from 30 to 200 hectares in size. any object burrow From time to time, each of the males makes brief, dis- with its tongue (e.g. tracks of other animals, the lizard lowers his tant excursions beyond the borders of his home range, entrances and so forth), slightly head. during which time he may visit the territory of a

It should be in mind that neighboring settlement. kept In ordinary conditions these behavior and body scheme. The real is com- of this is a simplified picture posture were observed during the most part period and nomadic individ- plicated by the presence of stray of monitor's activity when for example the hunting of uals among the settled ones, altering the make-up monitor travels over familiar area. "Confident gait" and so forth. The area of a settlement routine the settlements may be generally characterized as a pose of to a kind of for settled is in a state of amounts "public property" activity. In this time the animal psycho- this settlement. It is not is absent or inhabitants of specially logical comfort. A conflict of motivations did not observe territorial behavior behavioral guarded. We any it is possible to realize through the pattern or within them. The either between settlements several motivations simultaneously (e.g. the search for encounters degree of unrest and aggressiveness during food and a sexual partner in the course of search with acquaintances was. however, incontrovertibly behavior). The physical state of the animal and its lower than during encounters with strangers (Tsellar- external circumstances do not pose obstacles to the ius and Men'shikov 1994) and made the incorporation fulfillment of the corresponding type of activity The of newcomers into the settlement difficult. (Ovsyanikov and Badridze, 1989). mentioned in this article were majority of the animals in The "confident gait" was often observed course members of one of two settlements which adjacent of encounters between monitors (see section "Exam- were under constant surveillance. exs 1. ples of behavior of monitors...", 7; fig 14a). In the of research the hibernation lasts self-confidence and region This gait probably testifies to the approximately from the beginning of October to the calm of the animal. His contactant evidently inter- of 1.5-2.0 months after of such beginning April. During prets it as a threat of attack or the possibility monitors travel emergence from hibernation, widely threat. In all directly observed instances the approach and In an within their home ranges intensively forage. by "confident gait" provoked unambiguous social of monitors is this period the activity high response. The approached animal manifests anxiety into contacts with enough: they readily enter conspe- (see exs 7, 9 and Fig. 14, 16) or displays a peaceable- interest in their tracks, but males are rare. cifics and show great ness/submission (ex 1 ). The latter instances do not make any attempts to court the females in this Attack. When a monitor attacks a large prey he either (Tsellarius and Men'shikov 1994). Mating period a or immediately rushes on it, abruptly starting sprint, continues for a short time, it starts from the period of 3-5 sneaks up to it before rushing from a distance first days of June and comes to end till the twentieth m away. The sneaking up monitor walks with a rapid of June. Females, which have taken part in mating, the often uses shrubs and or step, creeping along ground, dig the nest burrows in the end of June beginning of relief of the land as a cover. The act of lowering him- the clutch 1-3 July, and diligently protect during self to the ground is also characteristic of the monitor months after deposition (Tsellarius and Men'shikov that is avoiding danger (Fig. 3b). When sneaking up 1995). Social activity of other animals rapidly and when rushing the monitor holds his head and tail decreases during 1-2 weeks after the end of mating an ordinary hunt all observed of moni- horizontally. During period. Mobility and activity of the foraging actions were directly connected with prey-catching. tors (females with clutches excluded) also decrease. In Any special displays were absent. general, posture In the end of July the range, daily inspected by a mon- of body of a monitor in assault is the same as in "con- itor, is a third or quarter of daily range in May. In fident gait". addition, in the second part of the summer lizards Attacks on were observed only in two may, from time to time, spend several days in burrows conspecifics situations: when a female her nest burrow without emerging to the surface. a) protects (Tsellarius and Men'shikov 1995); b) when an animal The Most Ordinary Behavioral Acts of Desert with a lower social status rudely breaks the "rules of for at a dis- Monitor etiquette", suddenly appearing, example, tance closer than individual distance (ex 4 and Fig. "Confident gait". The animal moves calmly, carry- 12). In such circumstances the emotional state of the his over the earth 2). The monitor ing body high (Fig. or attacking monitor may be characterized as anger lizard holds his head and tail horizontally and some- are rage. Any signals which expressed through spe- times the of the tail draws the earth while he tip upon an attack cialized postures and movements during 1997 Asiatic Research I Herpetological Vol. 7. p. I I

were not recorded. In 1992 we observed how a large rather closely linked to size, the duration of residence monitor, than the of in considerably larger proprietress a given settlement, and age. the burrow, returned repeatedly over the course of a "Sitting dog" posture. Monitor "sits down", few days to the nesting burrow of the female that we lifting of torso and head and had forepart looking around (Fig. named Biteress and attempted to dig up the bur- often 6). Very animal assumes this pose when at great row in her absence (Tsellarius and Men'shikov 1995). distance away is some disturbing object (observer, for The female, having found the arrival at work, drew example). "Sitting dog" posture probably is a classic close to him with quick dashes from shrub to shrub, orientation response. This reaction is formed with slightly lowering herself to the ground, and lunged at presence of weak fear (Hinde, 1970). him from a distance of 2-5 meters away. Biteress's A monitor often behavior was, down to the most minute details, simi- raises his head during contact lar to the behavior of a with subordinate individual when the latter assumes monitor stealing up to his prey. submission 5 and In all observed instances attacked animal immediately posture (exs.l, 3, Fig. 9). Therefore it be that the resorted to flight. may possible "sitting dog" posture (Fig. 6) or very similar pose also has a trace of dominance The "threatening gait". The lizard moves in the in it. "Sitting dog" posture was observed in course of direction of an adversary at a slow pace. His tail may conflict between males, when both contactants mani- not touch the but on certain ground may, occasions, fested an unwillingness to yield (ex 9). leave distinct imprints on both sides of his trail (giv- The lizard lowers his ing the impression that the lizard is whipping his tail "Stooping"". slightly head, his throat and enroute). When walking the monitor "drags his feet", simultaneously inflating pressing his tail to the sand This takes leaving distinct tracks in the sand from the dragging (Fig. 15a). place during the of encounter of an animal with an unknown in his ringers and claws. We can say nothing more object a definite about familiar area a a shirt on a this pose because it has been noted only (e.g. backpack, hung bush), in the event of in encounters whose course has been reestablished a careless movement of the observer in from tracks. hiding when the monitor lizard is not able to The track of "threatening gait", however, precisely the is very distinct from all other tracks. The female identify character and source of the movement, or a direct leaves such a trail when she moves away from her during encounter with another monitor that is unknown or whose intentions the animal is nesting burrow in the direction of an approaching con- not in a to specific. Such trails have also been noted a few times position determine, i.e. during an encounter with an irritant that attests not to an obvious on the part of the female who directed it at a male that danger but to the is of its In this circumstance the pursuing her. The "threatening gait" was recorded possibility beginning. state of in encounters between males when individual distance the animal may be characterized as a weak of fear, lack of self-confidence. was abruptly broken (ex 4. Fig. 12). In such a situa- degree unease, This state can even be tion the threat was always displayed by animal with unmistakably recognized in a liz- 1 ard's tracks because his tail in these instances higher "social standing" . In every instance, the ani- leaves a mal to which distinct, furrow in the sand and the threat was addressed sharply straight (Tsellarius Men'shikov changed the direction of his movement and in the 1994). of cases majority moved away from the site of events, Zatir. If the unease is combined with strong excita- sometimes taking flight. The lizards did not in the monitor engage tion, presses his cloaca and the hind part direct contact. of his abdomen to the sand and crawls, leaving behind a of flattened "Threatening gait" and attack were recorded in stripe sand (Fig. 5). This stripe serves as similar a very circumstances, sometimes "threatening signal mark which combines in itself visual and gait" was followed by an attack. The state of the ani- olfactory cues (Tsellarius and Men'shikov 1994). mal in "threatening gait" may be interpreted as anger Formerly considering the marking behavior of moni- tors in a special article (Tsellarius and Men'shikov 1994) we termed this act as "dragging" and mark itself as the "drag". The term is an unfortunate one as When speaking of the social status of an we had it is individual, being used for designation of another type of in mind the "frequency of dominance". In other words, the activity (Carpenter and Ferguson 1977). We propose more the monitors of a given settlement a subordi- occupy to use the transliteration of the russian term "zatir". nate position in relation to a given individual, the higher his of status. As one would expect, the social status of males "Showing the back". A monitor flattens the torso turned out to be rather closely linked to size, the duration of dorsoventrally and incline laterally in the direction of residence in a settlement, and given age. opponent, showing the back, as it were (Fig. 11. 13d). Asiatic Research 1997 Vol. 7, p. 112 Herpetological

At this time the tail is lowered, but not pressed, to the ing the displays of passive intimidation. In the rare cases an infuriated monitor fall into attack. The ground and the throat may be slightly inflated. The may of the the back" is monitor always orients himself laterally towards a state animal during "arching proba- threat. On certain occasions one may note a tendency bly very similar to it in "showing the back" but the fear into of "arching of the back". degree of fear is more high. A changes anger and as a degree of threat increases. We observed "showing of the back" when the rage monitor encountered retaliatory aggression (active "(Jape". If the danger is very serious and unexpected, self-defense) on the part of prey and during the hesi- the monitor will display extreme readiness for self- to tant behavior of a human who neither attempted defense: he opens his mouth wide (Fig. 8a) and lunges capture the monitor nor made any sharp movements in the direction of his adversary. Evidently this dis- alone. and yet did not leave the lizard During play attests to an extreme degree of fear. When a the back" was intraspecific contacts the "showing of monitor, which is sleeping near entrance of burrow, is one hand, more often observed in situations when, on being suddenly caught, he often convulsively moves the behavior of the it may be suggested that conspe- his legs wide apart, and feverishly turns his head with cific excites apprehension of the monitor, on the other opened mouth in all directions. At this time a is rather hand the motivation for present activity "strength" of heartbeat is noticeably increased. The to take to The emo- strong and monitor refuses flight. general picture shows strong resemblance to displays tional state in such situation may be characterized as of intense fear in man and other mammals (Darwin. alarm. 1872;Deryabin. 1974).

If another lizard both does not have self-confi- The "gape" may be followed by an attack. The the dence and does not disrupt the contact, showing animal becomes enraged, the urge for flight is curbed, back monitor may fall into active self-defence (ex 8). the monitor chases his adversary and, if he is success- of If the opponent does not manifest any symptoms ful in catching hold of the latter, can be very difficult with the moni- in fear and confidently goes on approach, to deter (Fig. 8b). "Gape" was observed only observed tor commonly takes to flight. We have never encounters of monitors with human. that attack or appeasement followed the "showing of "Lurking". If during an encounter with danger the the back". However, during contacts with human the monitor thinks that he has gone unnoticed, he will "showing of the back" may fall into the "arching of conceal himself by lying down and pressing himself the back". The latter may be followed by attack. tightly to the ground (Fig. 3a). Furthermore, depend- a "Arching of the back". In this posture (Fig. 7a) ing on the circumstances, the lizard will either remain self-defense the display of readiness for active (i.e. prone or exit stealthily (Fig. 3b). monitor orients himself towards his adver- laterally It is difficult to define the emotional state of a the tail is raised for a blow, and the head is sary, monitor in this situation. Some degree of fear takes turned in the direction of the danger) and elements of place for certain. However, "lurking" is not an invol- passive intimidation (i.e. the animal tries to appear untary display of fear unlike such reactions as "arch- larger than he actually is: the back is arched, the tho- ing of the back" or "gape". It should be kept in mind rax is expanded, the body is raised upon erect front that absolutely identical posture is typical of the state legs, and the throat is inflated) are combined. moni- of contentment (e.g. basking, resting of replete Such posture is assumed by a monitor when the tor in the shadow of bush and so forth). This thing danger is serious and paths to retreat are cut off. should be taken into account when the behavior of a as a "Arching of the back" is very common response monitor in intraspecific contacts is being interpreted. of In such contacts it in to a threat on the part human. It may be important for interpretation that an sometimes follows the "showing of the back". We encounter with danger the monitor's eyes remained in encounters between to have never seen this posture open (in every instance of this that we were able conspecifics. make out) and in state of contentment the lizard very

If the human does not manifest hostile intentions, often closes his eyes.

the animal slowly retreats (Fig. 7b). In the opposite The "lurking" is customary in the social interac- case the monitor deals a blow with his tail and, after tions of various species of lizards (Carpenter and Fer- is or starts as this, either takes flight (if a chance given) guson, 1977) and has traditionally been interpreted is usual to make a lunge in the direction of the aggressor. a display of submission. Such behavior a When lunging the monitor turns to his adversary characteristic of the desert monitor also. The female breaking the lateral orientation and strongly decreas- often assumes this posture during the approach of an Vol. 7. 113 I 997 Asiatic Herpetological Research p.

Characteristic of Certain of adult male (ex 1 ). In this case the "lurking" may truly Behavior Types he a display of submission, but we have never Interrelations observed such a on the of the subordinate posture part Manifestations of dominance. We were able to in encounters of males. On the other hand, however, closely observe the interrelations of some monitors we have observed how it is assumed by the obviously for a length of 3-4 years. During these years we and animal in response to a female's or larger stronger observed a stable asymmetry of behavior in all a smaller male's of readiness for active self- display encounters between certain individuals. One monitor defense (exs 2, 7 and Fig. 10. 14). We have never of two always (or in overwhelming majority of cases) observed that "lurking" follows display of fear, unease displays relatively more anxiety in contacts with or alarm during intraspeciric contacts. The primary another and another's tracks. We regarded the first significance of this posture is probably not a display animal as a subordinant. Another lizard displays a of subordinance as such but a display of a peaceable- self-confidence and was regarded as a dominant. ness. In general, recumbent postures are most char- In the case of monitors, the behavioral syndrome acteristic of contacts of a "friendly" type (see below). of dominance is divided into two groups of "symp- Flight. In encounters of a desert monitor with human toms". On one hand there are distinctive features of or another large animal the monitor seldom falls into behavior which are connected with the social status of at the first moment. a follows flight Usually flight an animal and which are manifest in many types of of the back", of the back" or "lurk- "showing "arching activity. These features are displayed from the first If a arises at a distance more than critical ing". danger moment of interaction during direct contact between latter is 4 to 8 the animal will lurk as one (the from m) lizards. On other hand there is the "behavior of the a rule. In cases the animal manifests opposite usually victor" which is displayed only in agonistic contacts a readiness for active self-defence. In the case when and only when the "correlation of forces" has been human does not show aggressive intents, the lizard revealed. will slowly retreat either stealthily (Fig. 3b) or keep- The idea was formed that behavior of monitor dur- ing the posture of readiness for self-defence (Fig. 7b) ing contact with conspecific is more strongly and falls into flight (if falls) only outside of oppo- impressed by the social status of the animal (i.e. gen- nent's sight. The flight is not accompanied by any eral experience and history of interrelations with con- special displays (Fig. 4). specifics at all) than by concrete dominance and encounters between monitors in the During major- subordinance. The lizard with low status even during of a is an action of ritual ity cases, flight probably an encounter with his subordinant sometimes displays nature. often taken without Very flight place any pre- the most anxiety than high-ranking animal in contact vious symptoms of fear (exs 5, 6 and Fig. 13). No with his dominant. On the whole, the behavior of a matter how the interaction would turn, in every high-ranking animal is distinguished by self-confi- observed incidence of and ritual "sniffing", fighting, dence: the monitor rarely displays signs of unease or. combat, on the of one of the contactants flight part rarer still, alarm. This is especially apparent in track- terminated the contact of the inevitably regardless ing studies (Tsellarius and Men'shikov 1994). Abso- to which contact have In the stage may progressed. lutely dominant in one of the settlements, the fourteen event of the retreated to flight, "conquered" generally year old male named Vasya, boasting a snout- vent a distance of 2-3 meters more 10-15 away, rarely length of nearly 600 mm and a weight of 3.5 kg, did meters, his usual afterward, with the resuming pace not display substantial alarm even upon encountering "victor" not intention to generally displaying pursue a human. In Vasya's case we did not observe postures 3, 5, 6, 8, 9). to this rule are those (exs Exceptions of active self-defence (Fig. 7a) at all. As a rule, the cases in which one of the contactants immediately monitor turned sideways towards the human encoun- sets about an attack (ex 4 and 12). In this case as Fig. tering him, lowered his head, and slightly inflated his well, however, the attacker's and the retreatee's rage throat. The "showing of the back" was faintly fear are certain in the first moment of encounter. only expressed if expressed at all. In such a position the From that on both and to point flight pursuit begin monitor first drew back a few steps and then moved take on the character of 12 increasingly display (Fig. away only at a slightly quickened pace, periodically and ex 4). It is of this behavior that in symptomatic sitting and looking back (Fig. 6). not one of the observed incidences did the attacker It is highly probable that, during encounters catch up to his adversary. between animals, behavior attesting to states of com- fort are devoid of any expression of a conflict of moti- vations (exs 1. 7 and Fig. 14) and is in itself a display Vol. 7. p. 1 14 Asiatic Herpetological Research 1997

of rank. have high We observed such behavior prima- it. For example. Mafiozi repeatedly visited the area of in males which have social rily high standing. Docentess's nesting burrow and even spent the night

Females assume a submissive 1 dur- may posture (ex ) with her in a single burrow (Tsellarius and ing such an approach by a male but low-ranking males Men'shikov 1995). It must be added that sexual con- display a great degree of alarm and often resort to tacts between these animals were not observed either

flight. The specific "threatening gait" and lifting of that year or later. the head are also apparently linked to high social sta- Characteristic of friendly contacts are the absence tus. or only very faint display of signs of unease on either Observers of monitor behavior have described an individual's part and the mutual display of "submis- absolutely unambiguous "victor's pose" that is sion" (exs 6. 10 and Fig. 17). During such contact the assumed when the victorious monitor mounts the lizards never hold their bodies high over the ground, defeated one (Auffenberg, 1981a; Deraniyagala. much as in normal movement or during the "threaten- 1958; Gaulke, 1989; Horn et al.. 1994). A posture of ing gait". The monitors lie down and either draw this sort (e.g. topping, riding, straddling) is character- together with short, a few steps at a time, crossings or istic of many species of lacertilias and is displayed in crawl across in each other's direction. Expressions of the course of both and sexual agonistic interaction a peaceful nature do not, however, impede the propo- (Auffenberg, 1981a; 1983; Carpenter and Ferguson. sition of ritual combat (exs 5. 6 and Fig. 13). 1977; Horn et al.. 1994; Noble and Bradley, 1933). In the case of the desert monitor, we observed such pos- Common Ceremonies and Their Probable Function turing only during mating attempts but it is impossible to rule out its use as a "victor's as well. pose" We designate as a ceremony those interdependent actions which Within a certain context, it is possible that, when occur during contact between two or one of the contactants assumes the posture of submis- more individuals and are directed at the maintenance or sion, the act of licking the "defeated" plays the role of establishment of certain social relations, and also a "victor's 1 In the rules which these actions are pose" (ex ). opinion of Auffenberg by guided. The social status of the (1981a), tongue licking in the case of Yaranus benga- contactants, the dynamics of their lensis has a signaling function. motivational and emotional states, and the displays connected with them determine the course of the cere- Displays of amicability. Informal contacts, founded mony and its result for each of the participants but are upon personal attachments, are common to many spe- not linked to the essence (goal) of the ceremony itself. cies of animals and may play a substantial role in the formation of the social structure (Panov. 1983b). A Mutual "sniffing". Mutual "sniffing" is an almost similar sort of connection probably exists in the case obligatory act in the encounter of two animals over a definite of Varanus komodensis (Auffenberg. 1981b), V. ben- period of time. Exceptions may include those galensis (Auffenberg. 1983), V. rosenbergi (Green and contacts connected with the protection of a nesting burrow King 1993) and some other species. In the case of and cases of sudden, involuntary violations of monitors, the basis for this connection probably lies in individual distance. In these situations one of the con- the habit of neighborhood as a familiar lizard evokes tactants may immediately resort to threat or attack, much less unease than a strange one (Tsellarius and omitting the "sniffing" procedure. Only in early the Men'shikov, 1994). It may be possible that the per- spring, immediately following emergence from sonality traits of an animal are of significance as well. hibernation, and in the period when all regular activity ceases before Mertens (1946) long ago noted the clearly expressed hibernation, was the "sniffing" proce- individual differences in character among monitors. dure rarely observed in encounters between animals. According to our observations, in the case of the Monitors encountering one another often (albeit not desert monitor, individual differences in the degree of always) did not engage in contact at all. and the to alter excitability, aggressiveness, ability During "sniffing" the monitors usually first lick behavioral in circumstances be patterns changed may the snout of their conspecific. then his side, the very pronounced. sacrum region, and the base of the tail. Sometimes

We only observed friendly contacts between set- "sniffing" proceeds without displays of alarm or unease the tled monitors whose home ranges were broadly over- on part of the contactants for the duration of lapping for a long period of time. The aggressive the ceremony (exs 6, 10 and Fig. 17). More fre- unease reaction of animals during such contact may be sup- quently, however, or alarm occurs. It is pressed to such an extent that the female guarding her extremely common for animals to display alarm after nesting burrow will allow another individual to visit mutual "sniffing" of the snout and to try to avoid 1997 Asiatic Herpetological Research Vol. 7. p. 115

being licked in the sacrum region. In these instances. always the one which originally manifested alarm to the monitors "waltz": they circle, as if attempting to the greater degree, dealt a blow with his tail which catch up with each other's tail (Fig. 13d. 15b). One or invariably put his adversary to (light. The larger male both the It of animals always "shows the back". the did not necessarily emerge victorious from the fight. contactants begin to display alarm at the very start of Nor was the victor necessarily a resident of the settle- contact, then they may immediately orient themselves ment on whose territory the encounter took place. not to the facial but to the sacrum region, which inevi- The frequency of fights probably depends on a leads to tably "waltzing". number of circumstances but first of all on the social

The motivation for "sniffing" is. apparently, quite structure of the population in a given area and at a strong. Animals frequently draw together and do not given time. In other words, it depends on the predom- interrupt their contact until each contactant has licked inance of a certain type of interrelation. The social the other, even when the other evokes in each a strong structure is not an unchanging, species-specific fea- unease (ex 8). ture. Although the interrelations between monitors in the of studies from 1991 to 1993 be char- The primary goal of "sniffing" is probably the region may acterized as in the receipt of certain information about a conspecific. highly peaceful, previous period these relations were, of a rather different Familiar animals are probably capable of recognizing evidentally. nature. The of monitors for each other by some external features. In every majority caught marking in 1990, males and females alike, had fresh, instance of contact between unacquainted individuals, deep scars or wounds located in the sacrum however, sex and reproductive state were determined primarily or on the shoulders, on the side. These only by olfactory means (Tsellarius and Men'shikov region rarely scars and wounds are reminiscent of the teeth tracks 1994). Therefore, it may be possible that the urge to which are left when a monitor takes in his lick one's conspecific has as its basis the urge to something "mortal In 1991 wounds and fresh scars were a receive information about the physiological status of grip". and from 1992-1993 were noted two times in the encountered individual. rarity,' all. Apart from this, however, mutual "sniffing" appears thereby to be a required ceremony in the Ritual combat. Ritual combat is that type of agonis- course of which the social status and the personal tic interaction in which animals enter into direct con- interrelations of the contactants are determined (or tact but measures which could lead to the mutilation confirmed). The analogous significance of the cere- of an opponent are excluded. Until now. ritual combat mony of "sniffing" has been well known for socialized in the case of the desert monitor has gone undocu- species of carnivorous mammals, canids in particular mented, although it has been described for many other (Schenkel. 1947: Lorenz 1969). species of this genus (Green and King 1993: Greer. 1989; Horn et al. 1994). Fight. We designate as a fight that type of agonistic- In ritual interaction in which: a) monitors enter into direct con- every instance, combat is preceded by the tact, b) measures are taken that can lead to the mutila- ceremony of "sniffing" (exs 5, 6 and Fig. 13). Combat be broken off at the initiative of of tion or death of the contactants. c) on both sides may one the partic- at moment and in the of cases this displays of anxiety and readiness for self-defence take ipants any majority took at the first of combat, the "cross- place in the course of the interaction. Following place very stage of necks" observed one Auffenberg (1981a) and other researchers, we treat ing (ex 6). We only instance of all-out ritual blows of the tail as measures which can cause mutila- combat (Fig. 13). Every instance of

ritual combat or the to it was noted tion, although, strictly speaking, in the case of moni- attempt propose contacts between animals from the same tors they are a ritualized measure, a lesser one. in only during settlement. contrast to bites which are likely to inflict injury on an opponent. Ritual combat was recorded only in the case of males. It be however, that such combat In all, we observed three instances which may be may possible, also takes females. At the end of June qualify as fights, although with some stretching the place among 1993. we observed the tracks of an encounter between point a bit. In each of the three instances unknown or unfamiliar males from various settlements entered two females from the same settlement, Frosya, five old. and The four old. The tram- into contact. Displays of alarm and unease were years Fourth, years of sand that remained at the of their clearly expressed by both sides (ex 8, Fig. 15). Fol- pled patch sight encounter was somewhat similar to those that are left lowing the "sniffing", accompanied by the "showing after ritual combat between males. followed of the back" and "waltzing", one of the animals. Frosya The Fourth's tracks for nearly 45 m to this patch. The Asiatic Research 1997 Vol. 7. p. 116 Herpetological

with the females were obviously within each other's field of ritual behavior connected primarily display dominance and is not a ritualization of the vision and both, probably, "showed their back" from of fight. time to time. From the trampled patch the females In the case of the desert monitor and some other headed in different directions. Notably. The Fourth varanids. all-out ritual combat is extremely rare in ran for nearly 17 m and Frosya moved at an easy pace. natural conditions. The reason for this probably lies In the case of certain varanids. ritual combat has been in the fact that a certain combination of circumstances between females, and in con- noted between males, must be present for ritual combat to occur: uncer- the sexes Gaulke. ani- tacts between (Auffenberg,1981a; tainty should exist in the interrelations between 1989). mals, their social status should be about equal, and

varanids is dominance in relation to one another unestablished. The significance of ritual combat for the case of an obvious in unclear (Greer, 1989; Horn et al.. 1994) and attempts In so doing, in inequality a (i.e. in the of cases) the of to link this type of interaction with the struggle for strength majority question have dominance is resolved the of "sniffing" and specific resource (e.g. food, territory, females) by process not been successful. In those cases where a few males direct struggle to establish seniority is unnecessary. skirmishes are competing on account of a female, In the conditions of a stable settlement, social ritual combat did not take have been observed but rearrangements, taking into account the long life Encounters near sources of food place (Carter, 1990). expectancy of monitors, are relatively rare: the ani- ritual combat but more often may lead to a form of mals know one another personally and the rank of Gaulke. proceed otherwise (Auffenberg. 1981b; each is known to all the rest. The need not only for of 1989). Territoriality for the majority varanids, combat but even for the sharp display of dominance the desert monitor, has not been established social structure is including rarely arises. In the event that the Tsellarius et al.. (Green and King, 1993; Greer, 1989; destabilized to the point that a large number of lizards In the case of the desert 1991; Tsellarius, 1994). appear that are not sufficiently well known to one stretch- monitor it is precisely these skirmishes which, another, the social rank of an animal is more likely to as territorial ing the point a bit, may be regarded (i.e. be established in a series of fights and the conditions settled male with an unknown ani- the encounter of a for ritual combat rarely take shape. mal, a female's guarding of her nesting burrow) pro- of Monitors ceeding more in the form of a fight than ritualized Examples of Behavior During interaction. Encounters with Conspecifics. with a If we examine ritual combat in the case of I . The encounter of a settled male female from varanids on the whole, then the impression is made a neighboring settlement. May 26, 1993. The Contac- that the essence of combat consists in the mutual tants: the male Mafiozi, six years old, SVL 475 mm, four old, attempt to knock over the opponent and assume the weight 1.3 kg; the female The Fourth", years 1.2 Over the course of two "victor's pose". The animal throws his front paw (or SVL 425 mm, weight kg. tracks but the front and the hind) over the back of his adversary years Mafiozi had encountered The Fourth's and tries to stand up over him. This is quite apparent until this moment probably had had no direct contact case. The Fourth had in both our photographs (Fig. 13) and in detailed with her, in this year in any into a burrow descriptions of combat among different species of been released the previous evening varanids (Auffenberg, 1981a; Davis et al., 1986; located seven meters from Mafiozi's shelter that night later than he Deraniyagala, 1958: Gaulke, 1989; Hom et al.. 1994). and in the morning came to the surface near his burrow, This grappling, the attempts of each opponent to did. On the morning Mafiozi, lying without hesita- attain the "victor's pose" while simultaneously trying spied the walking female, rose, and, female to frustrate the other, is the essence of the combat. tion or displays of unease, headed for her. The hind and Mafiozi. reached The struggle in a standing position on the legs immediately lay down having a sacrum After this he evidentally developed as an attempt to occupy more her, licked her head and region. It is the raised his head favorable position for toppling an adversary. sig- moved off a few steps to side, (Fig. from The Fourth. nificant that a struggle attained to the end has been 9) and lay down, turning away with an finished by "victor's pose" (Deraniyagala. 1958: Horn Mafiozi twice more approached the female, licked et al., 1994). interval of a few minutes between, and again her. after this did he move away. When the If this is true, then ritual combat is most closely Only with linked not with the fight for a specific object but

is a of 2 purely social interaction. Combat development A11 females mentioned in this section of article did not take

all of part in reproduction for period investigations. 1997 Asiatic Herpetological Research Vol. 7. p. 117

are male had left. The Fourth, not rising, lifted her head the males in the given settlement. The animals settlement and knew one but lowered it again as soon as Mafiozi turned towards members of the same her. After every lick of his tongue, Mafiozi lifted his another well for not less than a year before the of the conflicts between them before head high and held it this way for some time. encounter. None the one described below, or for a year and a half fol- 2. The encounter of an adult, nomadic male with a lowing it, have been noted. On the morning, Mafiozi, young, settled female. May 14. 1991. The course of around a bush, on Feodor. events was reestablished from tracks. The Contac- walking literally stepped who was basking in the sun after emerging from his tants: the male Grigory, seven to eight years old, SVL night shelter (Fig. 12). The latter jumped on him. 505 mm, weight 1.9 kg; the female Frosya, three apparently without warning, and Mafiozi jumped years old, SVL 425 mm, weight 1.6 kg. Grigory aside and took to Evidentally. for the first 15- hibernates in this region and in the summer appears flight. 20 m the monitors ran as fast as they could. For the here episodically, one or two times a month. Frosya next 15 m the of their step decreased. Feodor has lived in this area permanently for at least two length then shifted to a walk and followed Mafiozi for about years. The monitors came into contact while circling 5 m by the "threatening gait". As soon as the young a shrub from different sides (Fig. 10). Judging by the male also shifted to a walk, however, Feodor made a tracks, Frosya immediately turned sideways to the burst of speed, compelling Mafiozi to again take male and. probably, "showed her back". Grigory lay The chase continued in this fashion for more down at once. Having taken a few short steps in his flight. than 200 m. Finally, having startled Mafiozi again in direction. Frosya also lay down. After some time routine order, Feodor shifted to an easy pace and. Frosya rose and. walking around the male, left in the direction, went to one of the nearest same direction she had come before the encounter. sharply changing colonies of opimus where he began to Grigory followed her tracks for nearly 50 meters, Rhombomys hunt. Events proceed in like manner when a female is leaving powerful "zatirs", and then also moved in the chasing a monitor who has encroached upon her nest- direction he had kept to before the encounter. ing burrow. 3. The encounter of an adult, hut never impregnated, 5. Ritual combat between two settled males. June 1, settled female with a settled male. May 22, 1993. The 1993. The Contactants: Mafiozi and Edik. both 6 Contactants: the male Es the Ninth, eight years old, years old, measure SVL 475 mm, and weigh 1.3 kg. SVL 480 mm, weight 2 kg; the female Frosya, five The animals know each other well and have been years old, SVL 450 mm, weight 1.2 kg. The animals members of the same settlement for at least four have belonged to the same settlement for no less than years. At the end of 1992, the leader of the settle- four years and are well acquainted with one another. ment, the old male nicknamed Feodor, disappeared. In 1992, Es the Ninth persistently, but unsuccessfully, the remaining males Mafiozi is one of the courted Frosya. Frosya encountered Es the Ninth on Among largest and most energetic. He is active over the the morning when he was laying, half of his body entire space of the settlement and regularly goes far sticking out of his burrow, and slowly headed for him, beyond its borders. Edik's primary region of activity lowering her head and slightly inflating her throat. Es on the northeastern edge of this settlement and he the Ninth, obviously disturbed, made a movement in lays visits its central area only episodically. The encounter her direction, stooping slightly. Frosya "showed her took place on the morning. The monitors spent the back" and began to move off sideways, not letting the in the same of and 1 1 ran a night colony Rhombomys opimus male draw right up to her (Fig. ). Then she from their burrows almost It few meters away and the monitors froze. After a few emerged simultaneously. is highly probable that the animals had made contact seconds of immobility, the female slowly moved in the burrow. The lizards lay for a few minutes near away, frequently looking back. Es the Ninth remained the exit from the burrows and then Mafiozi moved in place until she was hidden from view, watching her toward Edik who, in his turn, took a few steps in his from behind in the "sitting dog" posture. Then he direction. Meeting, the monitors lay down and, lying attentively licked her track, left a zatir, and also down, licked one another first on the snout and then moved away. on the side and sacrum (Fig. 13a). Next, they crossed 4. A skirmish of two settled males that resulted from their necks, each attempting to deflect the neck of his the violation of individual distance. June 26. 1991. opponent to the side while simultaneously trying to The course of events was reestablished from tracks. seize with his paw the supporting foreleg of rival (Fig. The Contactants; Feodor, nearly 10 years old, SVL 13b). Until this moment neither of the monitors had 550 mm. weight 3.0 kg; Mafiozi, 4 years old, SVL displayed any alarm or substantial unease. Then. 430 mm, 1.5 kg. Feodor has the highest status among Asiatic Research 1997 Vol. 7, p. 118 Herpetological

ran a few meters switched to an Mafiozi succeeded in budging his opponent (Fig. 13c) himself, off, easy and left. Mafiozi licked his tracks and went off and the monitors began to "waltz" (Fig. 13d) at which pace, in a different direction. time Edik (left) "showed his back", displaying obvi- side ous alarm. At some moment the monitors were 7. The encounter between a settled male and a nomad. in the same to side and their heads were directed way. May 24, 1993. The Contactants: Alitet, 5 years old. front over Edik's Mafiozi immediately threw his paw SVL 470 mm. weight 1.4 kg; Shot Glass. 10-1 1 years at once. shoulders. The latter did the exact same thing old. SVL 560 mm, weight 1.8 kg. Alitet is a settled The lizards made attempts to overturn each other, slip- resident of the settlement on whose territory the their neck. One winter ping their heads under opponent's encounter took place. Shot Glas has spent the time that Mafiozi succeeded in doing this, the moni- within the borders of this settlement for at least three on their backs and ended in their of hiberna- tors rolled over up years but about a month after coming out shifted to the previous position. The lizards gradually tion goes far east and appears here only episodically, the "face to face" position (Fig. 13e) and. continuing for two to three days, until the end of the season of to rise on their monitors had not struggle, began hindlegs. Having activity. As far as we know, these and closed their front assumed a vertical position had direct contact this year, although they regularly males con- paws on each other's backs (Fig. 130. the came across one another's tracks. The encounter took their to their saw each other tinued vigorous attempts topple oppo- place on the morning. The monitors The males fell down a few times, at of 15 nent. together practically simultaneously, a distance nearly breaking their grip in the process (Fig. 13g), but meters, and froze motionless for some time. Then. seized one another immediately jumped up and Shot Glass decisively headed toward Alitet (Fig. 14a)

was conducted ener- 1 anew. The entire skirmish very who. having allowed him to approach within .5-2.0 the getically and the positions of opponents changed m. inflated his throat and "showed his back". Shot ran to the side for 3-4 m and rapidly. Edik suddenly Glass immediately lay down (Fig. 14b) and Alitet. one another for moni- the monitors watched motionlessly stepping slowly, walked around the recumbent nearly 30 seconds. Edik then slowly moved away, tor from the side and, looking back from time to time, back. describing a zigzag and frequently looking went away. About a minute later. Shot Glass rose and, in watched him from tracks Mafiozi, remaining place, pressing his tail to the ground, licked Alitet's his head. The entire from the the trail of his behind, raising struggle, (Fig. 14c). left a zatir, and followed the adversaries crossed necks, lasted no for 34 moment conspecific. Having followed the tracks nearly from longer than two minutes. The entire encounter, m. he "sniffed" Alitet's excrement and peacefully from their burrows, the moment the monitors emerged went away, sharply changed direction. lasted 14 minutes. 8. An encounter between two unfamiliar males which 6. Encounter and ritual combat between two settled Contactants: The ended in a fight. May 31. 1993. The males. June 2, 1993. The Contactants: Rhombik, 5 1.4 Tip. 6-7 years old, SVL 460 mm, weight kg; 445 1.2 Mafiozi is 2.2 years old, SVL mm. weight kg. Dusty. 12 years old, 590 mm. weight kg. The Tip his The older and larger (see ex 5 for description). is a settled resident of the settlement on whose terri- to the same settlement and have three monitors belong tory the encounter took place. For at least years. other well since at least 1991. On the of this set- known each Dusty has spent the winter near the borders evening of June 1. 1993. without our interference, the tlement but immediately after coming out of hiberna- in the same of Rhom- monitors spent the night colony tion has traveled to places located several kilometers a bomys opimus which that day. in the morning, to the southeast. In 1993 he remained in the region of young female from a neighboring settlement. The hibernation for the summer for the first time. The visited. from their noticed Fourth, had repeatedly Emerging encounter took place early in the day. Having monitors for a burrows the next morning, the lay long The Tip at a distance of about eight meters. Dusty lay time near each other, basking in the sun and yawning for a few seconds and then headed for The Tip who the usual in turn. Their behavior was not unlike immediately turned sideways to him. The Tip dis- monitor that have from his behavior of emerged night played greater and greater alarm as Dusty approached animals shelters. After approximately 30 minutes the and the "showing of the back" became more and more and the of mutual "sniff- inflated throat, crawled together procedure apparent (15a). Dusty's lowered head, 10 minutes. It was not accom- but ing" lasted for nearly and tail pressed to the ground appear threatening of unease. Mafiozi of self-confi- panied by any apparent displays actually attest to his unease and lack to then crossed necks with Rhombik and attempted dence. After the mutual "sniffing" of the snout. Dusty Rhombik freed but the latter press him to the ground. very calmly attempted to "sniff" The Tip's sacrum 1997 Asiatic Herpetological Research Vol. 7. p. 119

his a the shifted to a alter drew back, "showing back" ( 15b). As result, meters off, walk and 25-30 m entered monitors described a few circles in place. Suddenly, a burrow of Rh. opimus. C-59 immediately assumed a The Tip dealt a blow of his tail and Dusty quickly normal position and. once The Tip was hidden from scurried aside. Having moved about six meters away, view, walked about the site of the encounter, inspect- he stopped and the monitors watched each other for ing burrows, and then peacefully went away. some time. Then moved Dusty slowly away, barely- 10. A friendly encounter between an old male and a back. After one or two minutes The also looking Tip young male. May 12, 1993. The Contactants: Chuck left, not even been interested his having by opponent's Norris, not less than 10 years old, SVL 520 mm, tracks. weight 1.8 kg; Egghead, 4 years old, 425 mm, weight 9. An encounter between two unfamiliar males, June 1.2 kg. The home ranges of both monitors broadly IS. 1993. The Contactants: The Tip. 6-7 years old; overlap but lay beyond the boundaries of the region C-59, approximately the same age as The Tip but a bit where regular observations were conducted and their

larger, his SVL is 480 mm and he weighs 1.5 kg. C- status and the history of their interrelations is 59's home range is situated in a zone little settled by unknown. Having caught sight of each other, both monitors between two settlements located far from monitors lay down and for a long time crawled around one another. Hence, he periodically makes excursions each other, "sniffing" their partner's snout, side, and far beyond the borders of his range. The previous base of the tail, displaying virtually no signs of evening C-59 was released into a burrow not far from unease. From time to time the animals would break The Tip's night shelter in almost the center of the lat- off their activity and for 10-15 minutes lie near to ter's settlement. C-59 was caught nearly a day before each other, occasionally closing their eyes (Fig. 17). this. Over the previous three and a half years he had After this the "sniffing" was resumed. At the end of appeared in the given region not more than two or the encounter the young male began to make "zatirs" three times. Emerging from his night shelter in the (signal marks), crawling across Chuck's back and early morning, C-59 walked for some time about the neck in doing so, after which he left. The old male colony of Rhombomys opimus and, finding the burrow immediately entered a burrow. Contact lasted for 47 where The Tip had spent the night, hid in it. About 10 minutes in all. minutes later the monitor again appeared on the sur- face from a different opening, having traveled nearly Discussion three meters underground. Emerging from the bur- On a certain stage of investigation of social structure row, C-59 looked around, licked the sand, yawned, of population the researcher will inevitably clash with and. having moved a few meters away, lay under a necessity of a studying of mechanisms of the social bush, head raised. The Tip emerged from his own reciprocal influences, that is the problem of intraspe- burrow a few minutes later and headed confidently for cific communication. C-59 who remained in the very same posture but kept In classic the of animal commu- an eye on The Tip, turning his head to follow the lat- ethology concept nication is based on the three it is ter's movements. The Tip made a circle, having postulates: a) pro- drawn close to C-59 who at that moment rose half- posed that behavioral acts, that carry socially information, must be rather exotic, in order way, inflated his throat, and "showed his back" (Fig. important that a animal will be able to sin- 16a). Later. The Tip made yet another circle and perceiving correctly a communicative out of series of non com- again returned to C-59. Both monitors assumed the gle signal municative, routine behavioral acts; b) a "sitting dog" posture (Fig. 16b) and remained motion- less for some time, located at a distance of about two communicative act must be very stereotyped, in order that a monosemantic will be meters from one another. Then The Tip again began interpretation provided; a set of to certain act must be lim- to make a circle, at the same time inspecting the bur- c) responses strictly ited to its and coordination of inter- rows of Rh. opimus as if not noticing the newcomer. provide adequacy actions. a communicative is When he came near to C-59 the latter jumped up and Thus, system being considered as the of ritualized behav- turned in his direction, having lowered his head, system discrete, inflated his throat, and flattened his trunk dorsoven- ioral acts with fixed significance (Hinde.1970; Mac- Farland. 1985). A of communication is trally. The Tip did the same and the monitors simulta- process being as the succession of which neously lunged at one another. Each having struck the regarded stereotyped acts, is founded on either innate or learned automatism of sacrum of his opponent with his nose, and each "showing his back" (Fig. 16c), they made a full revo- responding. lution after which The Tip jumped aside, ran 9-10 Research 1997 Vol. 7, p. 120 Asiatic Herpetological

These three principles are formulated by Tinber- them the most important ones are such interdependent gen and his followers in course of investigations of factors as a) initial emotional state of contactants; b) a behavior of invertebrate animals, pisces and aves. It history of interrelations of given animals; c) a social should be noted that behavior connected with repro- status of animal, i.e. personal experience of previous duction (courtship, mating, parental care) was mainly intercourse with conspecifics. examined. This behavior is directed at the of reaching When a problem of decoding of any system of sig- limited set of aims. An strictly specific investigations nals arises, it should be useful to formulate a supposi- social behavior in mam- of "everyday" (especially tion of what a kind of information is transmitted by led to accumulation of facts which har- mals) poorly this system. It should be quite correct to use an analy- basic see Panov, monize with principles (for survey sis of nonverbal communication of our own species it should be admitted that 1983a). Evidently, develop- for solution of this problem. A majority of nonverbal ment of communication on the base of other princi- behavioral signals of Man carry information about the ples or on the base of several principles emotional and/or motivational state of an individual. simultaneously is possible. Direct information about the intents of an individual A contradistinction of exotic behavioral acts of the or his external circumstances is not contained in the desert monitor and non-exotic ones is very relative majority of behavioral acts. Nonverbal behavioral about circumstances and quite useless both for ascertaining of communica- signals carry information and/or individual so far as a tive significance of these acts and for analysis of their the intentions of given particular a forming and origin. In the point of view of a external circumstance frequently provokes particu- state in a researcher, who observes the monitors during all peri- lar emotional state and this emotional is. a base of a action. A ods of their activity, the "confident gait" is an element particular situation, particular of common, routine behavior, and the "showing of the human's response to behavioral signal may be very the his emotional back" is a bright, exotic posture. But in monitor's diverse and depends upon situation, It is evident that point of view the "showing of the back" or "stooping" state and his personal experience. is are far more usual acts than "confident gait", since communicative systems of other mammals orga- monitor observed his conspecifics during contacts nized in a similar way (Schenkel. 1947; Ladygyna- have not reasons only. Only the monitor's "point of view" is important Kots, 1958; Lorenz, 1969). We any for formation and evolution of his communicative sys- to expect some things of a fundamentally different tem. A coincidence of researcher's and monitor's nature in other higher vertebrates. about exoticness of the should be "points" posture It is strictly imagined that the majority of behav- in the case if a monitor would be aware possible only ioral acts of the desert monitor clearly reflect the emo- behavior with of his behavior and identify his own tional state of an animal and are in this regard that of a As far as we can conspecific. judge by perfectly unambiguous. But displays of even diamet- behavior of monitors contacts, all features of identical behav- during rically opposed states may contain behavior and are .exotic non-exotic, equally important ioral elements. In addition, the intensity of every for communication. emotional state may be various and, accordingly, the various too. Emotional A large majority of behavioral acts of desert moni- intensity of display may be exist tors may be expressed in varying degrees: they may states are not discrete and, between them, there It concerns the mani- be very distinctive or hardly noticeable. Many differ- an entire gamut of transitions. ent acts may smoothly turn one into another. Some festation of these states also. elements of behavior, of the throat signaling inflating It seems to us that, without an understanding of in which have for example, take part many displays, the dynamics of the motivational and emotional states It was noticed in distinctly different significance. of animals engaged in social interaction, a correct Panov and many species (Auffenberg,1981a; Zykova. interpretation of the course of these interactions and and. it is not an 1986; Hikida, 1989) evidently, excep- their result is often complicated or altogether impossi- tion, but a rule. ble. The data from our observations conforms poorly A human perceives the behavior of a conspecific to the of lizards as animals that widespread perception as a stream of integrated mental pictures. Separate behavior based sim- display relatively primitive upon elementary behavioral acts, as a rule, are not per- reactions. A behavior of the monitor ple stereotypical ceived individually. This stream of nonverbal signals encounter with is not an during conspecific definitely first of all influence the emotional state of the per- automatic to the behavior of Behav- response partner. ceiver, and do not act upon behavior immediately. ior is conditioned circumstances, by many among Adjustment of behavior is being realized by indirect 1997 Asiatic Herpetological Research Vol. 7, p. 121

way through a change of subjective feeling of situa- ,1968: Simonov. 1970). Probably emotions are a very tion and emotional estimation of it. It is quite proba- ancient mechanism of estimating the influence of ble that the mechanism of the animal's perception of internal and external irritants, which developed long of new cortex. and neu- conspecific's behavior is the same. If this suggestion before arising Morphological for of emotions is right, we arrive at a picture of nonverbal communi- rophysiological ground forming prob- arose cation as a "process of tuning each of communicants ably arose as long ago as the anamnia into the behavior of its partner" (Panov, 1983a). A (MacLean, 1949; Dethier and Stellar 1967). A pres- mechanism of this tuning is influence of animals the ence of afferent tone is the indispensable component emotional and motivational state of each other of conditioning reaction, without it a forming of feed- through the exchange of information about the alter- back mechanism is impossible (Wiener. 1958). ation of these states. Communication of this sort asks Essential resemblance of the behavior of lizards for to our own of analogy highly developed systems and mammals (MacLean, 1978; Regal, 1978; Tsellar- nonverbal such as music, dance, etc. communication, ius and Men'shikov 1994), unstereotyped course of During many decades amidst ethologists it was interactions, universality and non-discrete nature of considering as an indisputable tenet that animal's sub- the majority of lizard's signals (Auffenberg, 1981a; jective feelings (including emotions) are unable to be 1981b; 1983; Carpenter and Ferguson 1977; Gaulk, rather subject of scientific analysis. Actually it meant that 1989; Panov and Zykova, 1986), high ability existence of subjective feelings in animals is denied for education (Brattstrom, 1978; Krushinsky, 1977) since a veto upon the use of this idea for explanation make quite permissible the supposition that reptiles of mechanisms of behavior was imposed. But till now have rather developed forms of psychological activity. no one succeeded in creating a general theory of behavior within the bounds of behavioral approach. Acknowledgments and Psychologists neurophysiologists, having The work was financed by the Uzbek Zoological Farm looked at the matter the other round, a way propose and the USSR State Committee for Nature Protection of evolution of the psyche of vertebrate ani- concept and, following the disintegration of the Soviet Union, mals and influence of on their behavior. This psyche through contributions by the firm ALGA-ECO (Direc- well conforms to facts (Anokhin, 1968; Del- concept tor, S. V. Tsvetkov) and the Joint-Stock Company 1987; and Petrov, gado, 1969; Shepherd, Vartanyan "The LIKO Firm" (President, S. V. Vlasov). and at the 1989). a of emotion, one generally Using concept author's own expense. The authors are deeply grateful to obtain the harmonic, economical explana- managed to the volunteers who took part in the field work: M. tion of observed behavior. were Suppositions warily V. Borovkova, Dr. V. A. Cherlin. S. G. Davtyan. Yu. declared that not emotions, but also the higher only Derbyshev, A. Kuznetsov. N. Grefner, Dr. A. V. Gro- kinds of those are termed a psychological processes, mov. T. Makarova, Yu. G. Men'shikov. K. Mil'to. A. "mind" in to Man, are characteristic of ani- respect M. Murashev, A. Naryshkin, E. Yu. Portnov, Yu. Vos- mals 1985; MacFarland, 1985; (Gallup, Sevastyanov, trukhina and Dr. A. M.Zakharov. Without their help 1989). The existence of emotions is not called to the completion of this research would not have been question in respect to mammals with a developed possible. We would like to express our gratitude to brain. The analogy of basic and some secondary emo- Dr. N. B. Ananjeva (St. Petersburg), Dr. 1. S. Darevsky tions of Man and other mammals is not refused also. (St.Petersburg) and Dr. A. D. Poyarkov (Moscow) for But in to a use of the of emo- respect reptiles, concept their advice, Dr Kh. I. Atamuradov (Ashkhabad). Dr. tion is unusual for the of How- majority zoologists. T K. Kadyrov (Kyzylkum Preserve), Dr. S. A. Shepi- if we denied the existence of a border ever, sharp lov (Tashkent), Dr. A. E. Subbotin (Moscow) and Dr between the psyche of Man and that of other mam- O. I. Tsaruk (Tashkent) for their help in organizing the mals, we find ourselves before the necessity to seri- studies. I. A. Mukhin and E. Petukhov for their help in ously warrant a placing of such boundary-line in any processing the film, S. V. Chistyakova for her help in other case. preparing of manuscript of this article. Douglas Emotions are an internal regulator of psychologi- Greenfield and Betsy Lauppe (USA) for their help in cal activity and behavior, and are a universal measure translation of the article into English. On behalf of all of values that have a great adaptive importance. the participants in the field work, we would like to Under the shortage of prognostic information or thank K. N. Jhankaraev, A. Annagel'dyev, and the absence of possibility of processing of it the emo- other local residents who provided fresh water, provi- tional estimate of situation allows one to quickly find sions, and mail for our camp every month even when one's hearings and to make one's choice (Anokhin we were unable to pay for its transportation. Asiatic Research 1997 Vol. 7. p. 122 Herpetological

V .S. 1974. Passions. Emo- Literature Cited Deryabin. [Feelings. tions]. Nauka. Leningrad. 258 pp. (In Russian). Anokhin, P K. 1968. [Biology and neurophysiology Dethier. V G. and E .Stellar. 1961. Animal behavior: conditioned Medicina. Moscow. 547 of the reflex]. Prentice-Hall. its evolutionary and neurological basis. (In Russian). pp. New York. (Cit. after Russian edition, 1967. Nauka, W. 1981a. Combat behavior in Varamis Auffenberg. Leningrad. 140 pp.). Natural bengalensis. Journal Bombay History Society other Gallup. G. G. 1985. Do minds exist in species 78(l):54-72. then our own? Neuroscience and biobehavioral of the Auffenberg, W. 1981b. The behavioral ecology reviews 9:63 1-641. Komodo monitor. University of Florida Press, Gaulke. M. 1989. Zur Biologie des Bindenwaranes, Gainesville. 406 pp. unter Berucksichtigung der palaogeographiscchen W. 1983. behavior in Varanus Auffenberg, Courtship Verbreitung und der phylogene tischen Entwicklung In A .G. Rhodin and K. bengalensis. Pp. 535-551. der Varanidae. Courier Forschungsinstitut Sencken- Advances in and evolution- Miyata (eds). herpetology berg 112:1-242. Cam- ary biology. Museum of Comparative Zoology. Green, B. and D. King. 1993. Goanna (The biology Massachusetts. bridge, of varanid lizards). New South Wales University W. 1988. monitor lizard. Univer- Auffenberg, Gray's Press, Kensington. 102 pp. of Florida Press, Gainesville. 419 pp. sity Greer. A. E. 1989. The biology and evolution of Aus- H. 1978. studies in lizards. Brattslrom. B. Learning tralian lizards. Surrey Beatty and Sun PTY Ltd. 264 173-181. In N. Greenberg and P. D. McLean Pp. pp. lizards. National (eds). Behavior and neurology of Hikida. T. 1989. A behavioral study of the Japanese Institute of Mental Health, USA. five-lined skink, Eumeces latiscutatus. Pp. 449-458. C. and G. W. 1977. Variation Carpenter. C. Ferguson. In Current Herpetology in Eastern Asia. Herpetology and evolution of behavior in reptiles. Pp. stereotyped Society of Japan, Kyoto. 335.554. In C. Gans and D. W. Tinkle (eds). Biology Hinde. R. A. 1970. Animal behavior. McGraw-Hill of the Vol. 7. Academic Press, New York. Reptilia, Book Company, London. (Cit. after Russian edition, London. 1975. Mir, Moscow. 855 pp.). Carter. D. B. 1990. Courtship and mating in wild Horn. H. G.. M. Gaulke and W. Bohme. 1994. New Varanus varius. Memoirs of the Queensland Museum data on ritualized combats in monitor lizards (Sauria, 29(Pt. 2):333-338. Varanidae), with remarks on their function and phylo- and I. S. and N. L. Orlov. 1988. [Rare Garten N. F Darevsky. genetic implications. Zoologische and endangered animals. Amphibians reptiles.] 64(51:265-280. Shkola. Moscow. 463 pp. (In Russian). Vysshaya Khodzhaev. A .F 1989. [Present state and perspec- Darwin. C. 1872. The of the emotions in monitor in expression tive of preservation of desert Uzbekistan]. man and the animals. John London. (Cit. of 7-th Murray. Pp .270-271. In The problems Herpetology. after Russian edition. 1896: Ch. Darwin. Sobranie Kiev. 26-29 USSR Herpetological conference. sept. T. 2. sotchineniy, St.Petersburg). 1989. [Abstr.]. (In Russian). R.. R and A. 1986. Ritu- base of the Davis. Darling Darlington. Krushinsky, L. V. 1977. [Biological in Dumeril's monitors. Varanus Mos- alized combat captive mind]. Izdatel'stvo Moskowskogo Universiteta, dumerili. review 17(41:85-86. Herpetological cow. 272 p. (In Russian).

J. M. R. 1969. control of the of Delgado. Physical Ladygina-Kots, N. N. 1958. [Development psyche mind. and Row Publishers, New York. Lon- Harper in process of evolution of organisms]. Sovetskaya Russian edition. 1971. Mir. Moscow. don. (Cit. after Nauka. Moscow. 239 pp. (In Russian). 264 pp.). Lorenz, K. Z. 1969. Man meets dog. Penguin Izda- Dembowski. J. 1959. [Animal psychology]. Books. London. (Cit. after Russian edition. 1971. Moscow. 386 pp. (In tel'stvo Inostrannoy Literatury, Mir. Moscow. 164 pp.). Russian). MacFarland. D. 1985. Animal behavior. Pitman R. Y 1958. Pseudo-combat of the Russian edition. Deraniyagala, Publishing Ltd. London. (Cit. after lizard Varanus monitor bengalensis. Spolia Zeylanica 1988. Mir, Moscow. 519 pp.). 28(pt. 2): 159-160. Vol. 123 1997 Asiatic Herpetological Research 7. p.

183-202. In N. MacLean, P. D. 1949. Psychosomatic disease and the mental capabilities. Pp. Greenberg Behavior and of "visceral brain". Psychosomatic Medicine 11:338- and P. D. MacLean (eds). neurology 353. lizards. National Institute of Mental Health. USA. R. 1947. studies of wolves. MacLean. P. D. 1978. Why brain research on lizards.' Schenkel, Expression Behavior 1:81-129. Pp. 1-10. In N.Greenberg and P.D.MacLean (eds). and of lizards. National Institute Behavior neurology Sevastyanov, O .F. 1989. [Species-specific mecha- of Mental Health, USA. nisms of intercourse]. Pp. 141-164. In The behavior Mertens. R. 1946. Die Warn- und Droh-Reaktionen of the animal and Man: similarity and differences. Pushtchino. (In Russian). der Reptilien. Abhandlungen der Senckenbergischen Gesellschaft. Frankfurt a. M. Naturforschenden Shepherd. G. 1987. Neurobiology. T 2. Mir, Mos- 471:1-108. cow. 368 pp. H. 1933. The Noble. G. K. and T Bradley. mating Simonov, P. V. 1970. [Theory of reflection and psy- its on the of sexual behavior of lizards; bearing theory chophysiology of emotions]. Nauka, Moscow. 141 selection. Annals New York of Sciences Academy pp. (In Russian). 35:24-100. Stamps. J. A. 1977. Social behavior and spacing pat- N. G. and Ya K. Badridze. 1989. Ovsyanikov. [The terns in lizards. Pp. 265-334. In C. Cans and D. W. of comfort in of concept psychological interpretation Tinkle (eds). Biology of the reptilia. Vol. 7. Academic- motive powers of behavior]. Doklady Akademii Nauk Press, New York, London. SSSR 306(41:1015-1018. (In Russian). Tsellarius, A. Yu. 1994. [Behavior and mode of life in Panov. E.N. 1983a. [Methodological problems of desert monitor in sand deserts]. Priroda social investigations of communication and animal 1994(5):26-35. (In Russian). behavior]. Pp. 5-70. In Itogi nauki i tekhniki; ser. Zoo- Tsellarius, A. Yu. and V. A. Cherlin. 1991 . Individual T. 12. VINITI. Moscow. (In logia pozvonochnykh, identification and new method of marking of Varanus Russian). griseus in field conditions. Pp. 104-1 18. In Herpeto- Panov. E. N. 1983b. behavior and [Animal etiologi- logical researches, issue 1. LISS. Leningrad. cal structure of Nauka. Moscow. 423 populations]. Tsellarius. A. Yu„ V. A. Cherlin and Yu. G. pp. (In Russian). Men'shikov. 1991. [Preliminary report on the study N. L. Yu. 1985. Panov. E. and Zykova. [Comparative of biology of Varanus griseus in Middle Asia]. Pp. of and cauca- biology Agama sanguinolenta Agama 61-103. In Herpetological researches, issue 1. LISS. sica in Sumbar (Western drainage-basin Kopetdag)]. Leningrad. (In Russian). 185-204. In N. T. Nechaeva (ed). Plant and ani- Pp. Tsellarius A. Yu. and Yu. G. Men'shikov. 1994. Indi- mal communities of the Western Kopetdag. Ylym, rect communication and its role in the formation of Ashgabat. (In Russian). social structure in Varanus griseus. Russian Journal E. N. and L. Yu. 1986. on Panov. Zykova. [Notes of Herpetology 1(2): 121-132. behavior of sanguinolenta: everyday and com- Agama Tsellarius. A. Yu. and Yu. G. Men'shikov. 1995. municative behavior]. Zoologichesky zhurnal [Construction of nest burrows and clutch protection Russian). 65(2):235-246. (In zhur- by females of Varanus griseus]. Zoologichesky 1990. of biosocial Plyusnin, Yu. M. [The problem nal 74(1 ):1 19-129. (In Russian). evolution]. Nauka. Novosibirsk. 239 pp. (In Rus- Vartanyan. G. A. and E. S. Petrov. 1989. [Emotions sian). and behavior]. Nauka, Leningrad. 145 pp. (In Rus- V. 1990. role of hierarchic Polynova, G. [Functional sian). system of interrelations in lizard populations!. Zhur- Wiener. N. 1958. Cybernetics, or control and com- nal Biologii 5 1 (3 1:338-352. (In Russian). Obshchey munication in the animal and the machine. (Cit. after Polynova. G. V. and S. N. Panyushkin. 1982. [Terri- Russian edition. 1958. Sovetskoe radio, Moscow. 215 torial in Eremias relationships grammica]. Zoolog- pp.). ichesky zhurnal 61(31:385-394. (In Russian).

Regal. P. J. 1978. Behavioral differences between

reptiles and mammals: an analysis of activity and Vol. 7. p. 124 Asiatic Herpetological Research 1997

Appendix I

Figures 1-17

Figure 1 . Landscape of the region of operations, (photo by Yu. G. Men'shikov)

Figure 2. The carriage of a peacefully moving monitor, (photo by A.Yu.Tsellarius) 1W7 Asiatic Herpetological Research Vol. 7, p. 125

3. the monitor Figure Concealing himself, presses his body tightly to the ground (3a, above left) and remains motionless. The animal's eyes remained open in every instance of this that we were able to make out. Convinced that he has not been noticed, the monitor moves away from the site of the encounter after a short time, creeping the such that his elbows and along ground knees frequently rise higher than the level of his back (3b, above right). The animal from the observer in this moving away fashion uses shrubs and elements of relief so skillfully as cover

4. The of in Figure carriage the monitor flight. The animal is fleeing the observer, (photo by Yu. G. Men'shikov)

Figure 5. The male drags his body along the ground, flattening the substratum in his wake (signaling marks, below transliterated from the Russian as "zatirs") in the area which a female from his settlement (The Fourth) and males from a neighboring settle- ment (Rhombik and Mafiozi) had visited not long before. This took place on June 5, 1993 in a region where the borders of neighboring settlements touch and animals from both settlements visit, (photo by A.Yu.Tsellarius) Vol. 7. p. 126 Asiatic Herpetological Research 1997

Figure 6. The "sitting dog" posture. When the moni- tor is moving away from a site where he had encoun- tered danger, the more frequent display of the reference reaction "What's going on?" is quite appar- /W -- ent. The lizard periodically sometimes every few - steps sharply "falls" on his rear, raises his head and the frontal section of his body on erect forelegs, and looks around, (photo by A.Yu.Tsellarius)

Figure 7. The display of readiness for active self- defense characteristic of the monitor lizard facing a threat from a human or another large animal (7a, at left, top). If an opponent does not start an active oper- ations the monitor, continuing the display of readiness for defence, slowly retreats (7b. at left, bottom), (photo by A.Yu.Tsellarius)

Ul -a*

Figure 8. Finding himself in an unavoidable position, the monitor opens his mouth widely in the direction of the danger (8a. above left). An attack very frequently follows this and the monitor seizes his enemy in a "mortal grip" (8b, above right), (photo by A.Yu.Tsellarius) 1997 Asiatic Herpetological Research Vol. 7, p. 127

Figure 9. The male lifts a head moving away from the female which assumes the posture of submission (for detail see description of encounter in section "Exam-

>'."" ' of /-.' ples behavior...", ex 1). (photo by A.Yu.Tsellarius) imi!&m\ "

- Figure 10. Diagram of trails of encounter between male and female (for detail see ex 2). 1 male's trail and place - - - of lying; 2 zatir of mail; 3 female's trail and place of lying, 4 shrub.

Figure 1 1 . Female "shows the back" to familiar male which goes out of burrow (see ex 3). (photo by A.Yu.Tsellar- ius) Vol. 7. p. 12* Asiatic Herpetological Research 1997

- - Figure 12. Diagram of trails of encounter between two males (see ex 4). 1 trail of young male (a the step, b - - - - the run); 2 trail of old male (a place of basking, b the run. c "threatening gait").

*, >y»U- fl «, «

4 %. *3fe* r 4 m * F_ U"

ft 13a Figure Figure 13b

Figure 13c Figure 13d 1997 Asiatic Herpetological Research Vol. 7. p. 129

V* _ ».» - Z^JU^mM Figure 13e Figure 13f

Figure 13 (a-g). Ritual combat between males (for - - detail see ex 5). a mutual "sniffing'; b, c wrestling by necks; d - "waltz" with "showing of the backs"; e - tran-

• sition to standing position on the hind legs; f wres- - tling in vertical position; g loss of equilibrium, (photo by A.Yu.Tsellarius)

Figure 13g

14a Figure Figure 14b

Figure 14. The encounter of a settled male with a

- nomad (see ex 7). a the nomad heads for the settler

- by "confident gait"; b the nomad assumed a posture of appeasement; c - the nomad "sniffs" the track of the settler, (photo by A.Yu.Tsellarius)

Figure 14c 1997 Vol. 7. p. 130 Asiatic Herpetological Research

Figure 15b Figure 15a

- Figure 15. The encounter of a settled male with a new settler (see ex 8). a stooping new settler approaches to - the "host": b new settler (above right) attempts to "sniff" the sacrum of "host", (photo by A.Yu.Tsellarius)