Showing papers in "Behaviour in 1975"

The process of species-specific song recognition by the indigo bunting, Passerina cyanea, and its relationship to the organization of avian acoustical behavior.

Abstract: Songs of the Indigo Bunting, Passerina cyanea, mostly from Kentucky and Michigan, were analyzed for species-consistent characteristics. These were compared to sampled Lazuli (P. amoena) and Painted (P. ciris) Bunting songs to identify genus-consistent characteristics and possible directions of behavioral evolution. Playback experiments tested song organization in terms of the species-recognition function. The initial three to six figures in Indigo song appear to be specialized in structure and function. Average frequency ranges and durations of song figures progressively increase at the beginning of the song, while silent intervals between figures progressively decrease. These characteristics appear to have developed at different times. Another initial specialization is the presence of "introductory" figure types that are only found in the first or second figure position in the song, while all other figure types are likely to appear at any position in the song. Introductory figures form separate identifiable peaks in distributions of figure frequency and duration. They have fewer subsegments (unidirectional frequency modulations) than other figures. A playback experiment suggested that the structural specializations of the first few figures are functional in gaining attention of the species. In addition to the initial attention process, two other separate processes apparently take place. A playback experiment showed that stimuli releasing the strong territorial defense behaviors are different from those attracting the Indigos. Since the fine detail of the figures is probably distorted across the territory, grosser structures of the song are thought to be responsible for the attraction process. These apparently involve many of the most species-consistent parameters of bunting song. Included are the frequency ranges of Indigo and Painted Bunting figures and whole songs, as well as the absolute position of the frequency range of Indigo figures. Some frequency characteristics of successive figures were found to be species-consistent in all three species of Passerina. Yet, particular figure types are not consistently found to be associated with one another in Indigo Bunting songs. Figure durations are very similar for the Painted and Lazuli Buntings, but the two individual Indigo population samples are different, even from each other. Silent intervals between Indigo Bunting figures are species-consistent and distributed into two significantly different groups: the intervals between repeated figure types and the intervals between different figure types. Lazuli Bunting intervals are not significantly different in this respect. The roles of different species-consistent factors were tested in three playback experiments. They involve figures that were different from wild Indigo figures in various respects, and yielded almost no responses from Indigo Buntings. A playback experiment demonstrated that territorial display and attack behaviors are dependent upon the fine structure of the Indigo Bunting figures. Other playback experiments in which the fine detail of Indigo figures had been manipulated, indicated that the cues which release strong territorial behavior are highly redundant. Consequently, the figure details were examined for species-consistent tendencies. These tendencies include the relationship between frequency and duration of the figure subsegments of all three Passerina species, and the number of subsegments per figure for the Indigo. Of special note is the distribution of Indigo Bunting subsegment durations, which tend to peak at 0.89 centiseconds and multiples of that value. A theoretical model of song organization, development, and evolution is based upon these species-consistent subsegment durations.

Sequential and Temporal Properties of Behavior Induced By a Schedule of Periodic Food Delivery

Abstract: I. Five hungry rats were exposed to a schedule of periodic food presentation, receiving a single pellet every 30 sec., in an apparatus that permitted drinking, running, and other activities. The development, extinction, and structure of behavior sequences under this regimen was studied in three experiments. 2. All the rats developed a stable pattern of behavior after twenty or so half-hour sessions. The modal pattern was drinking early in the interfood interval, running in the middle, and food anticipation at the end. This temporal pattern was associated with different sequential patterns in different individuals. 3. Elimination of opportunity to engage in one or more activities resulted in an increase in other activities, but the increase was not in simple proportion to their frequency under baseline conditions. 4. In the steady state the sequence of behaviors in each interval appeared to be determined by two main factors: (a) post-eating time, and (b) the "momentum" associated with an ongoing activity. Differences among individual rats appeared to be due largely to differences in the second factor.

Male Discrimination and Investment in Asellus Aquaticus (L.) and a. Meridianus Racovitsza (Crustacea : Isopoda)

Abstract: The following observations are presented :-1) A description of male: female interaction in A. aquaticus and A.meridianus. This indicates the presence of a male discrimination mechanism in that large females are selected for the passive phase before their smaller counterparts. 2) Passive phase durations in allopatric and sympatric populations of A. aquaticus and A. meridianus. No significant difference was found between species; however two populations of A. meridianus differed significantly from each other (<0.05P). The duration of passive phase is shown to be substantial (means varying from 5.3-11.2 days). Intermittent pairing was shown to occur, in particular with small females. 3) The relationships between the parameters a) female size: day the passive phase commenced for each couple and b) female size: day each female became ovigerous. That is large females were found paired and became ovigerous before their smaller counterparts. Both relationships are shown to be significant (at 0.05 level of probability or less) in four of the five populations investigated. It is suggested these observations may be interpreted in the following way: Males of both species are selecting for passive phase association those females exhibiting a cue which correlates with imminent oviposition and large brood size. This cue may be female size or another characteristic which is correlated to size. This behaviour pattern yields an increase in offspring number to those males exhibiting it.

Behaviour of red deer (cervus elaphus l.) at calving time

Abstract: Red deer on the Isle of Rhum (Inner Hebrides) show a well defined calving peak in late May and early June. Just before calving, hinds leave their usual social groups and move away from areas of high population density. Calves spend most of the day lying away from their mothers and are visited at intervals. During these visits, mothers show increased vigilance and flight distance from observers. When disturbed close to their lying calves, hinds are unwilling to approach the calf's position and may move the calf to a new area during the following 24 hours. Calves select their lying position with care, preferring to lie in long vegetation in places where they are sheltered from sight and can see the ground in front of them. All these behaviour patterns change during the first four weeks after parturition. The behaviour of hinds breeding for the first time differs little from that of experienced mothers.

Chemical Prey Preference Polymorphism in Newborn Garter Snakes Thamnophis Sir Talis

Abstract: Newborn, previously unfed garter snakes (Thamnophis sirtalis) respond with prey attack and tongue flicking to water based extracts prepared from the surface substances of normally eaten prey and presented on cotton swabs. The present experiments demonstrate reliable individual differences in preferred stimuli among members of the same litter. (I) Of 12 snakes tested on six different days with redworm extract, minnow extract, and distilled water, six responded reliably more to worm and one reliably more to minnow. Redworm was overall more effective than minnow. Using two ranking procedures, individual responsivity to redworm was not correlated with responsivity to minnow. Although distilled water was relatively ineffective, correlations of individual snake scores to extracts and water were high and often significant, in contrast to the low correlations between extracts. (2) Of an entire litter of 13 snakes tested on seven days with extracts from two species of earthworms and two species of fish, 11 responded significantly more to worm extracts and one significantly more to fish extracts. The two worm extracts gave almost identical overall scores and the same occurred for the two fish extracts, with the worm being more effective. While individual responsivities to the two worm or two fish extracts were highly correlated, responsivities across worms and fish were not. A few snakes discriminated between individual worm or fish extracts. (3) In 15 sibling newborn snakes tested on three concentrations (100%, 10%, 1%) of earthworm and fish extracts, most responded more to worm regardless of concentration, a 1% worm extract being more effective than 100% fish. The method of limits was used in both ascending and descending sequences. (4) In all three litters, the snakes could be divided into a few discrete groups based on the relative preference for fish or worm extracts. However, there was wide individual variation in attack frequency, attack latency, and tongue flicking in absence of prey attack. (5) The results are discussed in terms of a genetically based perceptual polymorphism. The phenomenon's possible role in the natural history and evolution of snakes, especially the interaction with feeding experience, is elaborated.

A Comparative Study of Facial Expressions of Two Species of Pinnipeds

Abstract: Fur seals Arctocephalus forsteri and walruses Odobenus rosmarus show similar facial expressions in a variety of social and non-social contexts. In non-social settings, both species modify the facial appearance by erecting the mystacial vibrissae while grooming the forequarters, while yawning, and during olfactory/tactile investigation of objects. During naso-nasal greetings, vibrissae are often erected in fur seals, and are erected and moved against the interactant's mystacial pads in walruses. Highly submissive animals show: for A. forsteri, erection of the vibrissae, wide gape, relaxed lips, posterior retraction of the corners of the mouth, wide-eyed stare; for walruses, dorsomedial drawing up of the mystacial pads and erection of the vibrissae, imparting a 'pig snout' appearance. In high intensity threat, both species show facial expressions involving: for A. forsteri, slight lateral expansion of the mystacial pads, slight to moderate opening of the mouth, direct or oblique visual orientation from a head-up posture; for O. rosinarus, lateral and dorsoventral expansion of the mystacial pads, attendant exposure and stretching of the skin of the upper lip, especially around the bases of the tusks, and inflation of the rostrum posterolateral to the nostrils. The similarities of form and context of facial expressions used by the two species suggest common causation, but a greater number of those of A. forsteri is considered communicative, in agreement with known ecological and social characteristics of the two species.

Mate selection and colour preferences in lesser snow geese.

Abstract: The assortative mating which has been found in the dimorphic Lesser Snow Goose, Anser caerulescens caerulescens, could be explained if birds chose mates according to the colour of their parents and/or sibs. Three distinct captive flocks were tested for colour preferences in terms of: 1) approach response, 2) association preferences, and 3) mate selection. 1) Approach responses. Young birds placed in a choice situation had a significant preference for birds of the parental colour. Sib colour when different from parental colour appeared to modify their choice. If parents were removed during adolescence the early colour preferences could be altered, the most recent associations determining the preferences. The pattern of response did not change in tests carried out at the age of 3 months and repeated at 11 months. The presence or absence of auditory cues did not alter the pattern of response. No differences were detected in the responses of gosling to maternal versus paternal colour. 2) Association preferences. In an open field situation, birds usually associate with their peer group at both one and two years of age. The degree of association with the peer group is less at two years than at one year. When birds associate with non-peer group birds they show a distinct tendency to associate with birds which are the same colour as their peer group. 3) Mate selection. In the flock which was raised as a single large group, with virtually no parental contact, pair formation did not depart from randomness in terms of colour, suggesting that non-random mate selection in Snow Geese is not an inherent property but is a function of their prepairing experience. In the flock which consisted of families where the foster parents were of one colour and the sibs of a different colour, and in which the foster parents were removed after one year, the pairing at two and three years of age was non-random; pair formation reflected preference based on sib/self colouring. It is concluded that familial plumage colour does influence colour preferences in terms of approach response, association preferences and mate selection. However, continuous association with birds of parental plumage colour is a prerequisite for this colour to influence mate selection. If the parent is removed (as happens in the wild) the colour preference may be altered but it is more likely that the preference will be maintained through association with birds of familial plumage colour. Thus, directly or indirectly, parental colour will influence mate selection.

Individual Characteristics in the Calls of Reindeer Calves

Abstract: In a study of the individuality in the voice of reindeer calves, sound spectrograms of calls from IO equal-aged calves were analysed. The following variables were selected and measured as to the degree of inter-individual overlapping: A) Duration of the call. B) Fundamental frequency. C-E) Frequency of the first, the second and the third formant. F-G) Difference in frequency between the first and the second and between the second and the third formant. H) The shape of the fundamental. I-K) The shape of the first, the second and the third formant. The variables were considered distinct to a calf if they were overlapped to less than 25 percent by the range of the same variable in another calf. No particular variable characterized the calves throughout, but in relation to any other calf, each was characterized by one or more variables. It is suggested that the call is characterized by interaction of different features, by the "Gestalt" of the call. Although individuality has been shown in the structure of the calls, it has not yet been investigated to what extent the separate individual characteristics are actually recognized as distinctive by the mothers.

Sexual Discrimination in the Siamese Fighting Fish (Betta Splendens Regan)

Abstract: I. We recorded the responses of male Betta splendens when presented with various stimuli behind a transparent partition. The stimuli comprised i) live male and female B. splendens; ii) lifelike (motionless) models of male and female B. splendens; and iii) six stylised model B. splendens. The stylised models consisted of three pairs, one member of which had long male-like fins and raised opercula, and the other with short female-like fins and lowered opercula. The first pair had "aggressive", the second, "submissive", and the third, "reproductive" colouration. 2. The use of two techniques for comparing responses to the different stimuli was compared. Principal component analysis of unscaled data produced more satisfactory results than did clustering by single linkage on the basis of taxonomic distances calculated on scaled data. 3. The response by a male to a stimulus consisted of two categories of behaviour: "agonistic" display and nest-oriented activities. 4. The responses towards live males and females differed only in the relative amounts of "agonistic" and nest-oriented behaviour performed to each. A greater amount of "agonistic" behaviour was performed towards males. 5. Three main influences were found affecting a male's response to a conspecific: i) a tendency to perform all components of "agonistic" display and to inhibit performance of nest-oriented behaviour; ii) and iii) tendencies to perform particular components of the "agonistic" display. Thus the "agonistic" display was found to be complex and governed by at least three separate motivations. 6. The first influence varied according to the (perceived) sex of the stimulus, being great when the stimulus was a male, and slight when it was a female. The other two influences were independent of the nature of the stimulus. 7. Responses to lifelike, motionless models were very similar to those to live fish. 8. All male models and the "aggressive" female model were treated similarly to the live male. The other models were treated similarly to the live female. 9. A mechanism for sexual discrimination was proposed, in which a male is characterised by long fins and/or raised opercula, or, an unpatterned body. A female is characterised by short fins and a patterned body. Discrimination can be accomplished solely by use of visual stimuli.

Courtship of Drosophila Melanogaster : Rejection Without Extrusion

Abstract: 1. The experiments reported were designed to study the courtship behaviour of male D. melanogaster with virgin and inseminated decapitated females, which do not extrude their genitalia in response to courtship, and do not move. 2. Two new elements of behaviour which occur during the male's courtship were described. The names suggested for these are 'grasping' and 'rubbing'. 3. A clear distinction was seen in the behaviour of males towards virgin and inseminated decapitated females. Fewer males courted the latter, and those males which did court did so for a shorter period. 4. The courtship to the inseminated females contained a relatively lower proportion of attempted copulation than that to virgin females. 5. Operations were conducted on the tarsi of the fore legs and sex combs of the males to elucidate aspects of their possible role in courtship. 6. Males lacking both tarsi and sex combs performed very little courtship either to virgin or to inseminated decapitated females. Males with tarsi removed below the sex combs, and those with the tarsi of the hind legs removed did not court significantly less than normals, but the relative frequency of attempted copulation in courtship was changed. 7. Removal of the sex combs, leaving the tarsi intact, led to the total absence of attempted copulation, although other elements of courtship occurred frequently. 8. Hypotheses are offered concerning the evolution of the behaviour of extrusion, and concerning the possible roles of the sex combs in courtship.

Social Interactions in the Solitary Wasp Cerceris Simplex (Hymenoptera: Sphecidae) by

Abstract: The solitary wasp Cerceris simplex exhibits a variety of social interactions. In a nesting aggregation of this species females often abandoned old nests (voluntarily and involuntarily) and attempted to usurp burrows occupied by other females. These attempts were sometimes successful although they often failed forcing the searching female to hunt for still another burrow. Alternatively two or more wasps might provision the same nest for varying periods of time. It may be that nest-stealing behaviour has been, in some cases, a preliminary stage to the evolution of semi-social colonies in the Hymenoptera. This behaviour increases the probability that a female will try to enter and provision an already occupied nest; if the would-be parasite and the original occupant tolerate one another they could enjoy a variety of advantages through mutual occupation of a nest, including a reduction of the incidence of nest usurpation by other conspecifics.

Behavioural Transitions in the Reproductive Cycle of Barbary Doves (Streptopelia Risoria L.)

Abstract: The pre-oviposition phase of the reproductive cycle of the male Barbary dove is characterized by a series of behavioural transitions which lead to construction of a nest and incubation behaviour. The present study provides a detailed account of the early courtship phase of 14 pairs of male and female Barbary doves, given continuous access to one another, and analyses the temporal relationships between transitions in male and female courtship. Male aggressive courtship, consisting of chasing and bowing, declines rapidly within the first day of pairing and virtually disappears by the second or third day. In contrast, substantial levels of nest soliciting, a nest-orientated activity, continue to be displayed until the fifth day of pairing. There is, therefore, a differential rate of decline of early courtship patterns of the male such that the time spent in nest soliciting increases relative to that of aggressive courtship. A succession of further transitions takes place in the behaviour of the male. Thus, the male begins to display nest sitting at the future nest site on the second day of pairing. This behaviour reaches a peak on the third day of pairing and continues to be displayed until the seventh day of pairing; a period which is on average similar to the latency to oviposition (median, 7.0 days). The male also begins to gather nesting material on the second or third day of pairing and this continues until oviposition. Male transitions are accompanied by a series of comparable transitions in the female which are not in phase with those of the male. Thus, the female begins to display nest soliciting, similar to that of the male, on the first day of pairing, this reaches a peak on the second day of pairing and disappears on the fourth day. Female nest soliciting is replaced by nest sitting, which reaches a peak of display on the sixth day of pairing and continues until oviposition. The female also begins to build the nest on the second or third day of the interaction and accepts the greatest number of pieces of nesting material two days before oviposition. Male aggressive courtship appears to influence the female both in terms of subsequent behavioural transitions and reproductive development. Thus the duration of bowing shown during the initial interaction is positively correlated with latency to oviposition. Similarly, the latency to termination of both chasing and bowing is directly related to the onset of female nest sitting and the latency to oviposition. These correlations support the view that male aggressiveness may delay female behavioural and reproductive development.

Quantitative Observation of Behavior in Free-Ranging Macaca Mulatta: Methodology and Aggression

Abstract: Quantitative methods of data collection and analysis were used to assess patterns of aggressive interaction in rhesus macaques. Four social bands were observed for 488 hours over a twelve-month period using standardized observation techniques and behaviors and recording data on monkeys in both feeding and non-feeding contexts. The numbers of monkeys present within the prescribed observation areas, the frequencies of three aggressive behaviors and the occurrence of open wounds were recorded for three age-sex classes; adult males, adult females and juveniles. The data revealed that more monkeys were present in the observation areas during the mating season, that levels of aggression varied inversely with group size, smaller groups exhibited higher levels of aggression and that male and female aggression was higher during the mating season, while juvenile agonistic interactions reached a peak during the weaning and birth periods. There were 46% more aggressive acts in the feeding than in the non-feeding context but the seasonal and group patterns were nearly identical between the two contexts. Arguments were presented supporting the use of the interactions/hour/ possible interacting combination of monkeys as a dependent variable; the data from this study and comparisons with other reports indicate that this is a logical variable to use. Lastly, several methodological tests demonstrated that there are potential biases in the use of the traditional field-note method of data collection; only a small percentage of the total behavioral interactions are recorded with the field-note technique and there is a tendency to record a disproportionately greater number of interactions initiated by larger adult monkeys. These disadvantages of the field-note method must be weighed against the need for individual identification.

Territoriality in the Laughing Gull (L. Atricilla)

Abstract: Laughing Gulls (Larus atricilla) were studied in a tidal salt marsh located in Brigantine, New Jersey and on an island in the Gulf of Mexico to determine how nesting gulls respond to conspecific intruders. Gulls were observed in Texas and at Brigantine during the pre-egg stage. In Texas, Laughing Gulls set up pairing territories in the sand beach area next to the colony, and defended these areas against conspecifics. In New Jersey, pairing territories were often located on Spartina mats within the colony area. Twelve pairs of gulls were marked, sexed, and observed for eight to fourteen hours per day during the incubation period. An intruder was defined as any gull other than the nesting pair which landed within three meters of the nest. The interactions between the nesting pair and intruders were recorded for 1145 sequences. Eighty-five percent of all intruders were responded to with the following patterns: Long Calls (18%), Intruder Displays (45%), and Chases (22%). Long Calls and Intruder Displays were given by an incubating bird, while Chasing was performed by the mate standing nearby. Gulls flying over the nest were usually reacted to with a Long Call although Intruder Displays were sometimes given. Intruders landing within one meter of the nest were always given an Intruder Display by the incubating bird and were frequently chased by its mate. Intruders landing from one to two meters from the nest were usually given the Intruder Display: those landing two to three meters from the nest were usually chased. Gulls landing over three meters from the nest were usually ignored. The probability that an intruder was responded to decreased as the distance from the nest increased. The behavior of intruders was as follows. Fifty-three percent of the intruders landing within a meter of the nests were rapists or potential rapists. These intruders remained on the nest longer than did other intruder, and sometimes evoked pecking and attack from the incubating bird. Nest-material stealers (18%) remained on the nest for less time. Neighbors (7%) infrequently landed on the wrong nest but quickly flew to their own nest. In 22 percent of the cases the activities of the intruders could not be determined, since they were quickly repelled.

The evolution of mating systems in temperate zone dragonflies (odonata: anisoptera). ii. libellula luctuosa (burmeister).

Abstract: The behavioral ecology of Libellula luctuosa (Burmeister) (Odonata: Anisoptera) was studied at several ponds in northern New York State, U.S.A. The male Libellula maintained territories which were slightly overlapping on each pond. As many as six males utilized each territorial sector of the pond concurrently. Conspecifics showing submissive behavior were allowed on the mating site, and all males on the territory recognized and maintained the boundaries. These communal sites were primarily mating/ovipositing areas. Aggressive interactions among co-occurring males resulted in the establishment of a dominance hierarchy on each territory. The dominance hierarchy increased the reproductive efficiency of the dominant male probably by reducing interference with mating. Subordinate males occasionally mated. The relative advantage of dominance in mating attempts is quantified. The average number of males at the pond changed little during the day and males did not localize their behavior to specific parts of the pond. An individual male returned to the pond an average of 5 different days. While at the water, males either flew over a territory or perched adjacent to the pond. Individuals frequently left the pond and returned during the day. The amount of time spent in each activity depended on the time of day and number of conspecific competitors. Site attachment was low and males commonly flew to different territorial sectors. The dominance status of individual males often changed quite rapidly, especially when changing sectors or upon returning to the pond. Female Libellula occurred at low average daily density and showed no preference for specific areas of the pond or for certain times of day. Time budgets and analyses of mating behavior of Libellula luctuosa are considered with regard to the males' response to the availability and predictability of females and mating/ ovipositing sites. The behavioral patterns are analyzed with reference to a time-energymaturational-experiential hypothesis for the evolution of the behavior. Extensive comparisons are made between Libellula luctuosa (Burmeister) and Plathemis lydia (Drury).

The Effects of Dummy Size and Color On Behavioral Interaction in the Jewel Cichlid, Hemichromis Bimaculatus Gill

Abstract: The response of isolated, adult male H. bimaculatus to stationary dummies varies between individuals and, to a lesser extent, within individuals over a time period of several days or weeks. This is due, presumably, to differences in the relative activation of motivational systems that occur between individuals and to shifts in such activation within an individual, respectively. Certain activities that occur during dummy presentation - biting, quivering, fluttering and finrest - and which are considered to be associated with separate motivational systems of attack, sexual and escape behavior (ROWLAND, 1975) were utilized to study system interaction. An attempt was made to manipulate the different systems by presenting subjects with dummies of varying size and color. All of the activities listed above could be elicited, although in some cases only rarely, by each of the different size and color dummies. However, a dummy's effectiveness in eliciting a particular response depended both on its size and color. Males that attacked both red and green dummies often showed a higher bite frequency to the former. Biting in such males also tended to increase with increasing dummy size, but in most males a limit was reached, after which further increase in dummy size led to a decrease in biting. Indications that fluttering and/or finrest were increasing when biting decreased suggests that this drop resulted from interference of expression of the attack system caused by activation of escape. In several cases males attacked a green dummy but appeared to be inhibited from attacking the same size red dummy. It is suggested that this is because the red dummy strongly stimulates sexual behavior, which in turn, interferes with activities, such as biting, associated with the attack system. Moreover, males that had previously courted red dummies could be induced to attack them by allowing these males to pair and spawn with a live female (this effect was observed even several days after the female was removed) suggesting that deactivatian of the sexual system and/or activation of parental behavior will facilitate the expression of attack. Courting males showed much higher levels of quivering to red dummies than to green ones; quivering to green dummies was only occasionally observed. Quivering to red dummies also tended to increase with increasing dummy size, a result which could be due to increased conflict between attack and escape systems, increased activation of the sexual system, or both. There was some indication that fluttering was higher to red dummies, but this was not statistically significant. Fluttering and/or finrest tended to be higher in the presence of larger dummies than in the presence of smaller ones, at least in attacking males that showed some tendency to perform these activities. It appears that increasing size of a dummy tends to increase its effectiveness in activating behavior via a less specific arousal mechanism while the increased effectiveness of red coloration is due to a more specific mechanism. The results are viewed in terms of interaction among systems of attack, escape and sexual behavior and the role of such interaction in the causation and ritualization of courtship behavior is briefly discussed.

Défense Du Territoire Et Reconnaissance Individuelle Chez Xiphophorus (Pisces, Poeciliidae)

Abstract: On sait que chez les poissons du genre Xiphophorus, l'etablissement d'une relation hierarchique peut etre determine par les effets de la priorite de residence: les poissons qui ont ete isoles dans un nouvel environnement reagissent agressivement a l'intrusion d'un congenere et dominent le plus souvent des intrus de meme taille. L'objet de ce travail etait de savoir si la reconnaissance individuelle etait susceptible d'inhiber l'effet de la priorite de residence sur l'agressivite et la dominance des Xiphophorus ♂ ♂. Nous avons realise deux experiences differentes (exp. i, exp. 2), dont le schema experimental etait identique. Apres une phase pre-experimentale, au cours de laquelle un membre de chaque paire etait dominant (α) envers l'autre, les poissons domines de chaque paire (ω) etaient separes de leur despote et isoles pendant 3 heures. Ensuite, les anciens poissons α etaient introduits dans les aquariums qui etaient occupes par des anciens poissons ω. Dans les paires du groupe Experimental (E), les residents et les intrus s'etaient connus lors de la phase pre-experimentale; dans les paires du groupe Controle (C), les intrus etaient transferes dans l'aquarium d'un resident inconnu, qui avait ete domine par un autre poisson α au cours de la phase pre-experimentale. De la sorte, l'experience sociale immediate etait comparable pour les poissons des paires E et pour ceux des paires C ; les differences de taille entre les membres des paires E et C n'etaient jamais statistiquement significatives, et les membres des paires E et C etaient de morphologie semblable. Les resultats de la phase pre-experimentale ont demontre que l'agressivite et la dominance des poissons ne presentaient aucune difference significative avant l'application de la variable independante. Dans les paires de l'exp. 1 (48 paires), la duree de la phase pre-experimentale etait de 24 heures, alors que pour les paires de l'exp. 2 (60 paires), la duree de ce contact social etait de seulement 3 heures. Les resultats de la variable dependante ont fait apparaitre que les poissons des paires E et C presentaient des differences significatives dans la frequence de leurs comportements agressifs et de leur dominance. - Dans les paires de l'exp. i, les residents ont effectue beaucoup plus frequemment les premiers comportements agressifs (nages de menace, attaques) devant un intrus inconnu (paires C) que devant leur ancien dominant (paires E). Ces resultats ne sont pas apparus pour l'exp. 2. - Dans les paires de l'exp. I, le nombre des nages de menace reciproques etait significativement plus eleve entre les poissons des paires C qu'entre les poissons des paires E. Ce resultat ne s'est pas confirme pour l'exp. 2. - Dans l'exp. i comme dans l'exp. 2, la dominance des residents fut beaucoup plus frequente au sein des paires C qu'au sein des paires E. Dans la grande majorite des paires E, les intrus furent les poissons dominants; dans les paires C, au contraire, les residents ont domine deux fois plus souvent environ que les intrus inconnus. - Apres l'apparition d'une relation hierarchique nette, les poissons dominants de l'exp. i ont effectue un nombre total de comportements agressifs significativement plus eleve a l'egard d'un congenere inconnu qu'a l'egard d'un domine connu. Dans les paires de l'exp. 2, les dominants ont attaque davantage un congenere inconnu qu'un congenere connu. Au contraire, les approches des poissons dominants furent plus nombreuses au sein des paires E qu'au sein des paires C; par rapport au nombre de leurs attaques, les dominants de l'exp. 2 ont plus frequemment effectue des nages de menace devant un congenere connu que devant un congenere inconnu. Les resultats de nos deux experiences permettent donc de conclure que la reconnaissance individuelle inhibe les reactions aggressives et la dominance des poissons avantages par la priorite de residence. En consequence, la reconnaissance individuelle constitue un facteur plus important que la defense d'un territoire individuel dans la determination de la dominance chez Xiphophorus. Les resultats des paires C demontrent que l'effet de la priorite de residence sur la dominance est determinant apres un isolement de seulement 3 heures; les resultats des paires E demontrent que la reconnaissance d'un congenere individuel persiste apres un isolement de 3 heures. Dans notre discusson generale, nous envisageons les relations qui existent entre la priorite de residence et la territorialite; le fait que la reconnaissance individuelle favorise la stabilite temporelle des hierarchies au sein des paircs de Xiphophorus suggere qu'une veritable territorialite est absente chez nos poissons et chez d'autres Poecilides.

The Organization of Dustbathing Components in Bobwhite Quail (Colinus Virginianus)

Abstract: The components of dustbathing in 12 male and 12 female Bobwhite quail (Colinus virginianus) were described. These components form a sequence of entering the dust, pecking and scratching in the dust while standing, squatting in the dust, pecking and scratching in the dust while squatting, movements of the wings and feet to toss dust onto the ruffed plumage (dust toss), rubbing the head and side in the dust (head rub and side rub), rising, ruffling the feathers and vigorously shaking the dust out of the plumage (ruffle-shake), exiting the dust, and engaging in other behavior such as eating and drinking. Two tests were conducted at 1 day of deprivation of dust (to assess the reliability of both frequencies and sequences of components) and one test at 5 days of deprivation (to assess changes in these measures with increases in deprivation). The frequencies of seven of these components and the sequence in which the components first occurred had statistically significant reliability coefficients at both levels of deprivation. The frequencies of the components involved in driving dust into the plumage (dust toss, head rub, side rub) were significantly correlated. A statistic to measure the stability of these correlations was introduced. The frequencies of eight of the components showed significant increases with greater deprivation of dust. Male birds showed more of an increase with deprivation in the frequencies of the head and side rub components than did female birds. The sequence in which the components occurred was analyzed. The first occurrences of the dust toss, head rub, and side rub components were invariably in this order, for all of the birds tested at each deprivation level. The order of the first occurrences of the remaining components was variable. Individual components were generally repeated many times throughout a sequence; the order of each occurrence of each of the components was extremely variable between birds and tests. These results are discussed in terms of a lipid regulation model which suggests that dustbathing serves to remove lipid substances from the plumage.

Territoriality and scent marking by Centris males (Hymenoptera, anthophoridae) in Jamaica.

Abstract: 1. The behaviour of males of the three Jamaican Centris (Centris) species searching for females showed a gradation. (a) C. fasciata hovered often around food plants, but did not deposit scent. (b) C. decolorata hovered less often and scented less often a little in territories near nests. (c) C. dirrhoda hovered little and scented often in territories away from nests and food plants. 2. The scent used was detected in the males' mandibular glands and the sizes of these glands were directly proportional to the frequency of scent deposition. 3. A dominance hierarchy existed among C. decolorata males. 4. Males of a fourth species, C. (Hemisiella) crassipes, marked their territories with a secretion, probably derived from the hind femoral glands.

A description and analysis of agonistic behavior patterns in an opisthobranch mollusc, Hermissenda crassicornis.

Abstract: Observation of the encounters which occurred among pairs of Hermissenda crassicornis demonstrated the following: 1. Twenty percent of the encounters are agonistic, involving lunging or biting or both. 2. Agonistic behavior more often follows when the animals meet anterior-to-anterior than when they meet in any other configuration. 3. Initiators of encounters are more likely to win than non-initiators. They are larger than non-initiators and enter encounters head-first more frequently. Knowledge of either the position of the animals or the initiator allows relatively accurate predictions of the eventual winner. Additional knowledge of the size difference does not contribute to improved predictability. 4. The behavior patterns were recorded using I.5 second sampling periods. The sequence of behavior patterns is consistent with a first order Markovian model; this is primarily due to the strong tendency to repeat a pattern just displayed. One can predict the following behavior pattern with an accuracy of 1/3 to 1/4. 5. After removal of the repeated behavior patterns, the transitions between patterns are still consistent with a first order Markovian model. One can now predict the following behavior pattern with an accuracy of 1/5 to 1/6. There exists a greater possibility than before that higher orders of dependency might contribute to the sequence of behavior patterns. 6. The sequence of behavior patterns of agonistic encounters are more rigidly organized than the sequence of non-agonistic encounters. 7. It appears that winners and losers of encounters react in a similar manner to a given behavior pattern of the other.

Scent Marking With Urine in Two Races of the Bank Vole (Clethrionomys Glareolus)

Abstract: Male bank voles were observed to exhibit a high frequency of urination while exploring a novel area, but only a small amount of urine was released each time. It is suggested that this behaviour is a form of scent marking. Two geographically isolated races of the vole were investigated; these were Clethrionomys glareolus skomerensis from the island of Skomer, Wales, and C. g. britannicus from the mainland of Britain. It was found that Skomer males tended to leave trails of small drops of urine whereas mainland males typically released a smaller quantity of urine at each urination, often in the form of a finely drawn out trace. The frequency of urination was higher in mainland voles than in Skomer voles. The pattern of urination was found to be sexually dimorphic; females were less likely to urinate than the males and when they did so they tended to release single large drops. Urination observed during these tests did not usually result in the bladder being emptied in either males or females. Animals that did not urinate, or did so relatively infrequently, were also usually found to have urine in their bladders. In mainland males, and females of either race, there was no change in the frequency of urination as the animals became familiar with the test box. Skomer males, however, showed a decrease in the frequency of urination with repeated testing. Compared with urination, there was little difference between races or between sexes in the frequency of defaecation. The adaptive advantage of a modified pattern of urination, where urination constitutes a form of scent marking, is discussed, and the possible significance of the differences between the two races is considered.

Evolutionary Aspects of Communication in the Courtship Behavior of Four Species of Anomuran Crabs (Petrolisthes)

Abstract: Communication during courtship was investigated for exchanges of acts between male and female crabs of four species of the genus Petrolisthes (P. cabrilloi, P. cinctipes, P. eriomerus, P. manimaculis). Acts with a communicatory function can be derived from non-communicatory acts such as feeding, locomotion and tactile investigation of the environment. The communicatory acts are repetitive, conspicuous, and oriented toward other crabs. Several aspects of courtship were similar for all four species: the male crabs held a territory during courtship; courted female crabs performed movements of walking and stretching before copulation; and, just before copulation, the male nudged the female with his chelae and maneuvered her into the mating position with his walking legs. The courtship of P. manimaculis and P. eriomerus was similar in two ways : a pair of animals began courtship behavior an hour or two before copulation; the courting male performed maxilliped oscillations in exchange with the female's movements of walking and stretching. Although the males of these two species performed the same acts, the courting P. manimaculis performed many more communicatory acts than did the P. criomerus male. During the 30 min before the molt of the female one exchange of acts differed between the species for the courting pairs. Antennal taps of the P. manimaculis male were inhibitive of female's movements, but the same was not true for P. eriomerus. Acts which initiated and terminated courtship sequences also differed most significantly during this time for both species. If females perform the discriminating role in mate selection, then P. manimaculus and P. eriomerus females may distinguish the overall differences in frequency of the performance of the male's courtship acts, differences in the acts exchanged, and patterning of acts in sequences during courtship. The courtship of P. cinctipes and P. cabrilloi was also similar in two ways : a pair of crabs could begin courtship anytime between a day and a few seconds before copulation; the courting male performed the act of chelae rocking and the female performed movements of walking and stretching. Because of the variable duration of courtship it was impossible to demonstrate the exchange of male and female acts for the latter two species. The non-communicatory acts of feeding and swimming of Petrolisthes are anomuran in nature. However, those communicatory acts of Petrolisthes employing the chelipeds resembled acts performed by brachyurans having non-predatory feeding habits and chelipeds modified for display.

Les Cycles D'Activite D'Une Couvee Naturelle De Poussins Et Leur Coordination

Abstract: [Pendant les premieres semaines apres l'eclosion les couvees naturelles de poussins domestiques presentent le jour une alternance de phase d'activite exploratoire et de phases de repos pendant lesquelles les petits se blottissent sous la poule assise. Les ecarts temporels entre les axes des deux phases successives de meme nature presentent une regularite remarquable meme dans les conditions naturelles exterieures: en moyenne 30 minutes. Cette periodicite de la distribution temporelle d'activite existe chez l'adulte mâle et femelle, chez la couveuse au nid et chez les poussins isoles naifs ou experimentes. Elle persiste donc dans les couvees ou la synchronisation est assuree par des stimulations tactiles, visuelles et auditives reciproques. L'analyse de la structure interne des cycles, i.e. les parts respectives de l'exploration active et du repos, revele: - la duree moyenne quotidienne des phases actives augmente de 6-7 minutes (2-eme jour apres l'eclosion) a 18-20 minutes (apres une semaine). - la duree moyenne quotidienne des phases de repos diminue correlativement de 20 minutes a 8-10 minutes. Le premier jour d'exploration hors du nid, alors que les cycles coincident pour tous les poussins, les premiers eclos (donc les plus âges) sont les plus mobiles et explorent plus longtemps que les derniers nes. Une difference notable de l'experience precoce acquise dans cette periode vient donc aggraver naturellement la difference minime initiale dans l'âge reel (quelques heures). La qualite du substrat joue aussi un role sur la structure interne des cycles. Dans un milieu pauvre, stimulant peu l'activite exploratoire, la duree des phases actives tend rapidement vers des valeurs minimum (8-10 min.) quel que soit l'âge des poussins. La periodicite normale de 30 minutes peut etre modifee en profondeur par l'exposition prolongee a un synchroniseur social (vocalisations) de periode double. Une disharmonie provoquee par la substitution de poussins amene de graves repercussions sur la coordination des cycles entre les petits adoptifs et la couveuse ; celle-ci se montre incapable de s'adapter d'emblee a des poussins plus jeunes. Cependant la structure interne des cycles individuels peut etre aussi modifee par les interactions reciproques qui reajustent les deux parties en quelques jours., Pendant les premieres semaines apres l'eclosion les couvees naturelles de poussins domestiques presentent le jour une alternance de phase d'activite exploratoire et de phases de repos pendant lesquelles les petits se blottissent sous la poule assise. Les ecarts temporels entre les axes des deux phases successives de meme nature presentent une regularite remarquable meme dans les conditions naturelles exterieures: en moyenne 30 minutes. Cette periodicite de la distribution temporelle d'activite existe chez l'adulte mâle et femelle, chez la couveuse au nid et chez les poussins isoles naifs ou experimentes. Elle persiste donc dans les couvees ou la synchronisation est assuree par des stimulations tactiles, visuelles et auditives reciproques. L'analyse de la structure interne des cycles, i.e. les parts respectives de l'exploration active et du repos, revele: - la duree moyenne quotidienne des phases actives augmente de 6-7 minutes (2-eme jour apres l'eclosion) a 18-20 minutes (apres une semaine). - la duree moyenne quotidienne des phases de repos diminue correlativement de 20 minutes a 8-10 minutes. Le premier jour d'exploration hors du nid, alors que les cycles coincident pour tous les poussins, les premiers eclos (donc les plus âges) sont les plus mobiles et explorent plus longtemps que les derniers nes. Une difference notable de l'experience precoce acquise dans cette periode vient donc aggraver naturellement la difference minime initiale dans l'âge reel (quelques heures). La qualite du substrat joue aussi un role sur la structure interne des cycles. Dans un milieu pauvre, stimulant peu l'activite exploratoire, la duree des phases actives tend rapidement vers des valeurs minimum (8-10 min.) quel que soit l'âge des poussins. La periodicite normale de 30 minutes peut etre modifee en profondeur par l'exposition prolongee a un synchroniseur social (vocalisations) de periode double. Une disharmonie provoquee par la substitution de poussins amene de graves repercussions sur la coordination des cycles entre les petits adoptifs et la couveuse ; celle-ci se montre incapable de s'adapter d'emblee a des poussins plus jeunes. Cependant la structure interne des cycles individuels peut etre aussi modifee par les interactions reciproques qui reajustent les deux parties en quelques jours.]

An experimental analysis of the use of location calls by japanese quail, coturnix coturnix japonica

Abstract: Three experiments were undertaken to study location calls used by Japanese quail. The first experiment was carried out to examine differences in emission of structurally similar locaton calls by Japanese quail, Coturnix coturnix japonica, in different contexts. Such comparisons may reveal the possible course of evolution of one call from another. Comparison between the unmated male Japanese quail's crow and the mated male's separation crow indicates the following similarities and differences: a. The same physical unit, the three part crow, is being used in both instances. The same inter-individual differences between crows of unmated males are also found between their separation crows. b. A staccato call normally accompanies separation crowing whereas this is not the case in crowing of unmated males. The individual notes of the staccato call closely resemble those emitted by the male while tidbitting. c. The crow emitted by unmated males is louder and less variable in intensity than is the separation crow. d. Separation crows occur in temporal groups or bouts whereas the crows of the unmated male usually occur individually. Initial crows within a bout are relatively faint. The second experiment was undertaken to study the function of the separation crow, the staccato call, and the cricket call. In this experiment, pairs of quail were successively housed in a series of interconnected compartments. Separation and contact maintenance were controlled by the animals own movements. The calls emitted by the animals were tape recorded and their positions were recorded every 5 seconds. Three lines of evidence for the three calls serving as location calls were examined: 1. The call is emitted primarily when visual contact between animals is attenuated or absent. 2. The call is answered with another call that is a known location call. 3. The call causes locomotor behavior in the receiver that results in contact maintenance or establishment. The data show that the cricket and separation crow serve as location calls and provide evidence for the staccato call serving as a location call as well. The effect of increased ambient noise level upon the emission of the separation crow when separation is due to movements of the male and female was also assessed. Significantly more separation crows and instances of separation crowing occurred during the high ambient noise level condition. Analysis of the positional data indicate that the differences are not due to differences in visual contact. The effect of ambient noise level on separation crowing was explained in terms of 2 factors: a. A direct stimulatory effect upon the male perhaps due to masking of the fainter staccato call as well as the separation crows emitted by the male. Previous work by the author supports this conclusion. b. An indirect effect upon the male caused by masking of noises and vocalizations emitted by the female. Data from a third experiment in which male separation crowing was measured under conditions of visual and visual and acoustical isolation from the female support this conclusion.

Aggressive communication by Larus glaucescens. III. Description of the displays related to territorial protection.

Abstract: This paper is a description of the aggressive activities of the Glaucous-winged Gull, Larus glaucescens. It provides a descriptive basis for the interpretation of experiments designed to elucidate the aggressive communication of this species (STOUT & BRASS, 1969; STOUT, WILCOX & CREITZ, 1969; and in progress). The descriptions of the aggressive behavior of L. glaucescens were based on the analysis of 12,000 feet of motion picture film, and on the physical analysis of a large number of sound spectrograms (sonograms) of each of the aggressive calls. The behavior observed was classified with respect to its association with attack, escape, or other aggressive interactions, and also with respect to its production by territorial defender or intruder. The Aggressive Upright, Moving Aggressive Upright, Intimidated Upright, Trumpeting, Mew, Grass-pulling, Jabbing, and Choking displays were described. The Forward display, as described for other larids, was not seen. The physical analysis of the aggressive calls of the Glaucous-winged Gull demonstrated great similarity between the Trumpeting and Yelp Calls. The Courtship, Parent-young, and Aggressive Mews were demonstrated to have consistent physical differences. It was suggested that they could each have a different function. The Choking and Alarm Calls are similar in that they have a more complex harmonic structure than the other calls. However, a differential function has already been demonstrated for these two calls (STOUT, WILCOX & CREITZ, 1969). It was hypothesized that each of these aggressive displays communicates distinct levels of threat. The combination of head level (posture), call, orientation, and movement were considered as possible factors resulting in the distinction between displays. It was suggested that the Upright Threat, Trumpeting, Mew, and Choking displays communicate increasing levels of threat in that order. This model was evaluated in relationship to experiments performed on aggressive communication by L. glaucescens.

A Comparison of Feeding, Spacing, and Aggression in Color Morphs of the Midas Cichlid. I. Food Continuously Present

Abstract: The Midas cichlid (Cichlasoma citrincllum) is an abundant fish in the lakes of Nicaragua. Many populations are polychromatic, about 7 to 10% of the adults being variously white, yellow, orange, or red, and without the species-typical markings. These are termed 'golds' because the most frequent color is yellow-orange. The common cryptically colored morphs are called 'normals'. In the experiment, 6 equal sized small fish had to approach a feeder guarded by a Midas cichlid twice their mean weight. In the experimental groups, 3 of the small Midas cichlids were gold and 3 were normal (mixed color groups). The control groups were of two types, one with all 6 small fish gold, the other with all 6 normal (pure-color groups). In half of all trials, the large fish was gold, and in the other half normal in color. Data were gathered on Days I and 3. I) Differences in the behavior of large fish toward the small ones were not statistically significant. However, the large gold attacked the small fish more often than did the large normal, although the rate of attacking was remarkably low. The large gold fish also fed on average much more often (9.7/hr.) than did the large normal (0.7/hr.), whose mean rate was about half that for all small fish. 2) There was little difference in rate of feeding among the small fish. However, on Day 3, only, the small fish fed significantly less in the presence of a large fish whose color they shared. 3) The spread in weights within each group of small fish increased 1.4 to 2.4-fold during the four days of the experiment (growth depensation). 4) The distribution of the fish within the arena was recorded at 30-sec. intervals, and analyzed with regard to Near (to the feeder), Mid, and Far Regions, adjusting the data to fish per m2 per hr. There were no significant differences in distribution in relation to fish coloration. The small fish occurred at about the same rate in the Near and Mid Regions, but more frequently in the Far. The shelters in the Far Region had an effect equivalent to adding more space. 5) Across all experiments and groups of small fish, the rate of attacking was, in the Near, Mid, and Far Regions, respectively, 9.1, 19.4, and 14.7 per m2 per hr. When these data were modified to take into consideration the fish available for attack in the same region, the scores became 10.5, 22.4, and 15.0 per m2 per hr., respectively. Small fish, therefore, were about half as likely to attack in the Near Region, with the feeder and the large fish, as in the Mid Region. 6) The small fish attacked significantly less those small fish that shared the color of the large fish. 7) Small golds, in mixed color groups, were attacked less than were small normals. 8) Attacks by golds on normals were compared to those on golds by region and by day. Likewise, the attacks by normals on golds were compared to their attacks on fellow normals. In total, there were 24 such pairs of comparisons for the mixed color groups. Of these, 50% were significantly different. In 11 of these 12 cases, golds were attacked less than were normals. And 9 of these 11 cases had the large fish gold. Thus sharing the color of the large fish conferred some immunity from attack. When both the small and large fish were gold the effects summated in the favor of small golds to produce significant differences. Conversely, when the large fish was normal the effects of gold coloration and that of not sharing the color of the large fish cancelled one another. 9) All the small golds had had prior experience with normal colored siblings, but most of the small normals had never been with golds before. The attack suppressing effect of gold color on normals was pronounced on Day I but weak on Day 3. This suggests that the effect of gold coloration is enhanced by infrequent exposure. If so, golds should experience a lessened advantage in aggressive interactions in direct proportion to their abundance in a population. 10) We hypothesize that gold coloration decreases the readiness to attack in the perceiver by stimulating incompatible fear responses.

Aggressive Behaviour in the Zebra Finch Taeniopygia GuttataI. Fighting Provoked By Male and Female Social Partners

Abstract: In the domesticated Zebra Finch, unpaired males behaved sociably towards one another, but could be provoked to fight by the sight of a female nearby; the amount of fighting shown depended on the distance to the female. Qualitatively similar aggressive behaviour was provoked between males by the sight of a male, and between a male and female by the sight of another female. However, males were less effective than females in provoking fighting between females, and pair-bonded females were more effective than non-bonded females in provoking fighting in mixed or male dyads. Homosexual pair bonds had a similar effect to heterosexual ones in stimulating attacks on a male, but had not effect on aggressive behaviour towards a female. The aggressive behaviour seen could not be due to redirection of aggression, since the stimulus properties which were necessary to provoke attack on another individual were those relevant to sexual behaviour, and were different from those necessary to elicit attack on the individual itself. It is shown that in other cases of apparent redirection of aggression in sexual contexts, a similar conclusion can be drawn, indicating a link between the motivational systems controlling sexual and aggressive behaviour. Since stimuli from an individual may both sensitize a bird to respond aggressively to stimuli from other individuals, and elicit attack by the bird on the individual itself, a distinction between these modes of action (similar to TINBERGEN'S distinction between releasing and motivational effects) is necessary.

Les Relations Sociales Chez Le Cobaye Domestique MaleI. Etude De La Hierarchie Sociale

Abstract: I. La hierarchie sociale etablie entre les mâles de plusieurs groupes de Cobayes domestiques a ete etudiee. Un indice hierarchique base sur le rapport du nombre des agressions exercees et subies par un meme animal permet de determiner avec precision le rang de chaque individu. 2. La hierarchie observee est strictement lineaire et sa stabilite est bonne. Toutefois les periodes d'activite sexuelle correspondant a l'oestrus des femelles peuvent etre a l'origine de renversements hierarchiques entre mâles proches. 3. quantitative precise montre un maximum d'agressivite chez les mâles a et , ce dernier etant aussi le plus agresse. Les mâles les plus inferieurs sont peu agressifs et moins agresses que l'on pouvait le supposer. La hierarchie tend a s'estomper a leur niveau. De plus, chaque mâle agresse de maniere privilegiee son subordonne immediat. Les postures ambivalentes sont observees seulement entre a et entre lesquels la competition s'etablit a son maximum. 4. Les sequences de comportements montrent une ritualisation importante des postures utilisees mais varient selon les couples de mâles qui s'opposent. Ceci permet de penser que les mâles d'un groupe ont une certaine connaissance de la situation hierarchique de chacun d'eux. 5. Cette modulation des patterns comportementaux apporte confirmation du role de la situation dans les sequences de communication et de l'adaptation des reponses en fonction de l'experience passee et de l'environnement immediat.

Les Relations Sociales Chez Le Cobaye Domestique Male

Abstract: [Nous avons etudie les reactions comportementales de Cobayes mâles dominants places en presence d'un etranger, sur le territoire de ce dernier ou sur leurs propres territoires. 1. Il est possible de decomposer les affrontements en trois phases: - Une phase d'approche et de prise de contact. - Une phase d'affrontement pendant laquelle les animaux vont etablir des relations de dominance. - Une phase finale ou les relations preetablies se confirment, chaque animal subissant en quelque sorte son propre statut. 2. L'analyse de la deuxieme phase permet d'obtenir de longues sequences comportementales. Il apparait que le dominant presente dix fois plus de SAS offensifs que defensifs alors que le domine possede une balance comportementale equilibree. 3. Le comportement d'un animal apparait determine de maniere statistique par: - Le comportement de l'adversaire, - Le comportement anterieur de l'individu lui meme. Premierement, les actions offensives entrainent preferentiellement une reponse defensive, chez les deux animaux, les actions defensives du domine entrainent les reponses offensives du dominant. Neanmoins, les postures ambivalentes offensives provoquent generalement des reponses offensives de meme type. Deuxiemement, en plus de ce determinisme externe, une tendance generale a l'escalade aggressive se manifeste chez les deux opposants, ainsi qu'une tendance a l'escalade defensive chez le domine seulement. Il se confirme ainsi que l'affrontement est l'expression d'un conflit agression-fuite dont le point d'equilibre est constitue chez le Cobaye par la Posture Offensive Oblique. 4. La comparaison entre la hierarchie de groupe et les affrontements permet de penser que ceux-ci sont un moyen de resolution du conflit et d'etablir des relations de dominance par selection des reponses adaptees a la situation c'est-a-dire en definitive aux reactions de l'adversaire. L'ontogenese sociale et l'affrontement parviendraient ainsi au meme resultat par des moyens fort differents. Le comportement, loin d'etre stereotype, serait alors l'expression d'une situation instantanee (sequences interindividuelles) et de la memoire de l'animal (experiences prealables, comportements anterieurs). Cette derniere serait susceptible au niveau du systeme nerveux de provoquer une modification adaptative des reponses observees. 5. Enfin, la nature des deux combattants apparait predominante sur le lieu de la rencontre, ce qui laisse supposer l'existence d'une variabilite agressive individuelle dont l'origine est encore imprecisee., Nous avons etudie les reactions comportementales de Cobayes mâles dominants places en presence d'un etranger, sur le territoire de ce dernier ou sur leurs propres territoires. 1. Il est possible de decomposer les affrontements en trois phases: - Une phase d'approche et de prise de contact. - Une phase d'affrontement pendant laquelle les animaux vont etablir des relations de dominance. - Une phase finale ou les relations preetablies se confirment, chaque animal subissant en quelque sorte son propre statut. 2. L'analyse de la deuxieme phase permet d'obtenir de longues sequences comportementales. Il apparait que le dominant presente dix fois plus de SAS offensifs que defensifs alors que le domine possede une balance comportementale equilibree. 3. Le comportement d'un animal apparait determine de maniere statistique par: - Le comportement de l'adversaire, - Le comportement anterieur de l'individu lui meme. Premierement, les actions offensives entrainent preferentiellement une reponse defensive, chez les deux animaux, les actions defensives du domine entrainent les reponses offensives du dominant. Neanmoins, les postures ambivalentes offensives provoquent generalement des reponses offensives de meme type. Deuxiemement, en plus de ce determinisme externe, une tendance generale a l'escalade aggressive se manifeste chez les deux opposants, ainsi qu'une tendance a l'escalade defensive chez le domine seulement. Il se confirme ainsi que l'affrontement est l'expression d'un conflit agression-fuite dont le point d'equilibre est constitue chez le Cobaye par la Posture Offensive Oblique. 4. La comparaison entre la hierarchie de groupe et les affrontements permet de penser que ceux-ci sont un moyen de resolution du conflit et d'etablir des relations de dominance par selection des reponses adaptees a la situation c'est-a-dire en definitive aux reactions de l'adversaire. L'ontogenese sociale et l'affrontement parviendraient ainsi au meme resultat par des moyens fort differents. Le comportement, loin d'etre stereotype, serait alors l'expression d'une situation instantanee (sequences interindividuelles) et de la memoire de l'animal (experiences prealables, comportements anterieurs). Cette derniere serait susceptible au niveau du systeme nerveux de provoquer une modification adaptative des reponses observees. 5. Enfin, la nature des deux combattants apparait predominante sur le lieu de la rencontre, ce qui laisse supposer l'existence d'une variabilite agressive individuelle dont l'origine est encore imprecisee.]

Individual Distance in the Hermit Crabs Clibanarius Tricolor and Clibanarius Antillensis

Abstract: The distances at which individual hermit crabs (Clibanarius tricolor and C. antillensis) showed agonistic behavior patterns was recorded after the animals had been held at one of two densities for a week. 1) Behavior patterns differed significantly in the average distance of separation when they were executed. 2) For almost all patterns, there was considerable variability in the distances at which they were shown. 3) Part of this variance in distances was due to the behavior of the other crab. 4) Density treatment affected the distances at which behavior patterns were shown, the crabs held at the lower density having greater distances. Apparently as a result, lower density crabs lost more interactions. 5) The distances at which behavior patterns were shown were not correlated with either absolute or relative size of the acting crab. 6) Comparison of distances in intraspecific and interspecific interactions indicated very similar behavior in the two species, except that C. antillensis was not as clearly affected by the density treatment.