Showing papers in "Behaviour in 1977"

The social regulation of population density and age-sex distribution in the toque monkey

Abstract: [The relationships between behavioral, ecologicaland demographic data are examined for a wild population of nearly 450 toque monkeys, Macaca sinica, of Sri Lanka, based on 3½ years of continuous, plus 3 years of intermittent study. Under relatively stable ecological conditions troops fluctuated in size within limits, and the net growth of the population was zero (Ro = 1). Decrease in food supply caused a net decrease in population size. An abundant food supply stimulated population growth. A lifetable indicated that mortality differed markedly according to age and sex, and that this pattern was not attributable to predation or disease alone. Behavioral analysis revealed that 81.5% of all threats occurred during foraging. Threatened individuals were prevented from feeding, and their foods were usurped directly in 36% of all threat interactions. The observed frequency of threats between age-sex classes during foraging differed significantly from two progressively stronger null hypotheses. These hypotheses took into account, respectively, the age-sex distribution of the society, and the frequencies of nearest neighbor associations between animals of different age and sex. The agonistic discrimination between animals of different age and sex was mirrored by a similar affiliative discrimination. Some conclusions of this analysis were that adults dominated the juveniles which in turn dominated the infants, and among juveniles and infants males dominated their female peers. Adults likewise discriminated against the young females. The behavioral relationships during foraging influenced the foraging efficiency of animals, which was measured by the amount of time spent in foraging, feeding rates, and the quality of foods that were consumed. By these measures adult males fared best, then adult females, then juvenile males, and juvenile females fared worst. I proposed that as a consequence of these behaviorally imposed feeding efficiencies, young animals died at greater rates than adults, and infant and juvenile females died at greater rates than their male peers; behaviorally mediated access to other resources is likely to influence mortality in a similar manner. During the mating season, threatening and wounding increased markedly among adult and subadult males that competed for mates and that migrated. The peak of migration rates in males occurred during the subadult phase and coincided with the peak of mortality in males. This suggested that the rigors of migration (low priority of access to rcsources and frequent wounding) underlie the observed mortality. Mortality in adult males was (1) less than in subadult males which migrated more frenuently, and (2) greater than in adult females which do not migrate. Competition between troops, in part, determines the amount of food available per troop, and thereby contributes to setting the upper limit to troop size. The molding of the age-sex structure is then determined by social processess within a troop. I hypothesized that the effects of social behavior (mainly aggressive and affiliative behaviors) and possibly its nature, change in accordance with the age and sex distribution of the society, its density, and available resources. Social behavior determines, through socially imposed mortality, the age and sex distribution and density of the society (and hence the population) in such a way as to maximize the reproductive success of some of its members, and results in bringing the society (and population) towards an equilibrium state (Ro = 1) with the resources and non-socially imposed mortality., The relationships between behavioral, ecologicaland demographic data are examined for a wild population of nearly 450 toque monkeys, Macaca sinica, of Sri Lanka, based on 3½ years of continuous, plus 3 years of intermittent study. Under relatively stable ecological conditions troops fluctuated in size within limits, and the net growth of the population was zero (Ro = 1). Decrease in food supply caused a net decrease in population size. An abundant food supply stimulated population growth. A lifetable indicated that mortality differed markedly according to age and sex, and that this pattern was not attributable to predation or disease alone. Behavioral analysis revealed that 81.5% of all threats occurred during foraging. Threatened individuals were prevented from feeding, and their foods were usurped directly in 36% of all threat interactions. The observed frequency of threats between age-sex classes during foraging differed significantly from two progressively stronger null hypotheses. These hypotheses took into account, respectively, the age-sex distribution of the society, and the frequencies of nearest neighbor associations between animals of different age and sex. The agonistic discrimination between animals of different age and sex was mirrored by a similar affiliative discrimination. Some conclusions of this analysis were that adults dominated the juveniles which in turn dominated the infants, and among juveniles and infants males dominated their female peers. Adults likewise discriminated against the young females. The behavioral relationships during foraging influenced the foraging efficiency of animals, which was measured by the amount of time spent in foraging, feeding rates, and the quality of foods that were consumed. By these measures adult males fared best, then adult females, then juvenile males, and juvenile females fared worst. I proposed that as a consequence of these behaviorally imposed feeding efficiencies, young animals died at greater rates than adults, and infant and juvenile females died at greater rates than their male peers; behaviorally mediated access to other resources is likely to influence mortality in a similar manner. During the mating season, threatening and wounding increased markedly among adult and subadult males that competed for mates and that migrated. The peak of migration rates in males occurred during the subadult phase and coincided with the peak of mortality in males. This suggested that the rigors of migration (low priority of access to rcsources and frequent wounding) underlie the observed mortality. Mortality in adult males was (1) less than in subadult males which migrated more frenuently, and (2) greater than in adult females which do not migrate. Competition between troops, in part, determines the amount of food available per troop, and thereby contributes to setting the upper limit to troop size. The molding of the age-sex structure is then determined by social processess within a troop. I hypothesized that the effects of social behavior (mainly aggressive and affiliative behaviors) and possibly its nature, change in accordance with the age and sex distribution of the society, its density, and available resources. Social behavior determines, through socially imposed mortality, the age and sex distribution and density of the society (and hence the population) in such a way as to maximize the reproductive success of some of its members, and results in bringing the society (and population) towards an equilibrium state (Ro = 1) with the resources and non-socially imposed mortality.]

Status signaling in harris sparrows some experiments in deception

Abstract: (1) Harris Sparrows signal their social dominance status by variations in the amount of black feathering on their crowns and throat. The potential ability of individuals to cheat on such a status signaling system was experimentally investigated by dyeing and bleaching some free-ranging individuals in a flock attracted to a bait station. As discussed in detail, cheating is a theoretically important problem because survival studies have shown subordinates to be much less likely to survive over winter than dominants. If true, this should result in strong directional selection toward the dominant plumage type. (2) Subordinates dyed to mimic the highest ranking birds of the winter hierarchy were, with but one exception, persecuted by the legitimate studlies. The single exception was apparently a bird which had underestimated his status during the fall molt when the appropriate plumage signal is produced. (3) Bleached birds were forced to fight much more for their status, as dramati. cally shown by what was likely the first encounter between a bleached bird and a normal individual of just slightly lower rank. Eventually the bleached birds behaved as though all others around them were perceived as disrespectful, and despotically attacked birds at an abnormally high rate. (4) While these data strongly suggest that cheating is socially controlled, such a social organization raises some complex evolutionary issues. An alternative explanation of the apparent social control of cheating is that the unusual behavior observed in response to my manipulations merely represented normal defense of winter resources. This explanation requires that the rate of winter dominance inter-actions be controlled by (1) the risk of attack, and (2) the importance of resource defense. If this is true, the dyed birds may have appeared sick since no hormonal manipulation accompanied their dyeing; thus they may have been attacked more because perceived risk was down and potential gain high (beat the toughy while he is down). Likewise, the bleached birds may have become unusually aggressive because the closer approach of low ranked birds suggested to them that a much more active defense of resources was required. Experiments distinguishing these hypothesis have not yet been performed.

Snake Mobbing By California Ground Squirrels: Adaptive Variation and Ontogeny

Abstract: California ground squirrels (Spermophilus beecheyi) commonly live in association with and are the prey of snakes. Field observations indicate that encounters between the two may often include mobbing by the squirrel and defensive behavior by the snake. Our research had three goals : 1) to systematically observe and describe these mobbing interactions in both field and laboratory situations; 2) to compare in the laboratory the intensity of mobbing gopher, garter, and rattlesnakes by squirrels from two populations which encounter rattlesnakes (rattlesnake adapted), and one which does not (rattlesnake nonadapted) ; 3) to record and describe reactions to a garter snake by young snake-naive squirrels from rattlesnake adapted and nonadapted populations. We found the following. 1. Squirrels approached snakes, investigated them in elongate postures, bobbed their heads, flagged their tails, and sniffed snakes. Aggressively motivated squirrels kicked sand at the snakes, displayed lateral postures, pounced on, and bit them. 2. The stressful impact of this behavior upon the snake is documented by positive correlations between indices of mobbing intensity by squirrels and indices of defensive behavior by the snake. 3. Squirrels from both rattlesnake adapted populations mobbed snakes less intensely than the rattlesnake nonadapted squirrels. 4. The adult-like response of young snake-naive squirrels to a garter snake was significantly stronger than to a moving novel object, thus demonstrating that their response to the snake was based upon stimulus parameters other than novelty. 5. Snake-naive young from a rattlesnake adapted population mobbed less intensely than snake-naive young from a rattlesnake nonadapted population. 6. Snake-naive young mobbed more intensely than wild-caught adults. We proposed the following. 1. Snake mobbing may benefit ground squirrels by reducing the snake's hunting efforts in the area in which mobbing occurred. 2. The presence of venomous snakes increases the risk to the mobber, thereby favoring an adaptive attenuation in mobbing intensity. 3. Because young squirrels are often left at the burrow by foraging mothers, it is likely that first encounters with snakes often occur in the absence of adults. Under these conditions natural selection might favor predetermined epigenesis of the ability to recognize and respond appropriately to snakes. 4. Young snake-naive squirrels may not be as capable as adults of recognizing immobile snakes. Their enhanced response, relative to adults, to moving snakes may be an adaptive mechanism which permits the young to learn to recognize static snake form.

Individual Recognition, Intragroup Cohesion and Intergroup Spacing: Evidence From Sound Playback To Forest Monkeys

Abstract: The contexts and functions of several loud mangabey vocalizations, particularly the "whoopgobble", were investigated observationally and experimentally. Whoopgobbles are notable for their audibility and distinctiveness over long distances, their temporal pattern of delivery, and particularly their stereotypy and individual distinctiveness. On the other hand, contexts of and responses to these vocalizations are variable and sometimes nonobvious. In order to control context and more systematically investigate response, an experimental method involving playback of recorded vocalizations was developed. Although precautions against habituation were necessary, mangabey responses to playbacks were clearcut and repeatable. Answering vocalizations, changes in group movement, and changes in the dispersion of individuals within a group occurred only in response to mangabey vocalizations. Whoopgobble playbacks provoked a pattern of response, including most notably the rapid approach of one adult male (the "RA" male) from each group, which was specific to this call. Playback of whoopgobbles between 100 and 600m from mangabey groups indicated that this call does transmit information regarding the identity of the vocalizing individual and group over these distances. Test groups moved away from neighboring- and unknown-group calls, but towards those of their own males - particularly those of RA males. RA males, on the other hand, do not approach calls of other males from their own groups. Within a group, whoopgobbles may thus increase cohesion and influence the direction of movements. Characteristics of whoopgobble form and context are discussed with regard to hypothesized functions of these and other forest monkey loud calls. Responses by free-ranging mangabeys to playback of the whoopgobble confirm its role in maintaining distance between groups. Response was found to be independent of group size, despite the fact that whoopgobble rate is closely related to this variable and thus could transmit such information. Since responses were also found to be independent of location within the home range, intergroup spacing among mangabeys appears not be be "territorial", site defense does not occur. Nevertheless, the central areas in at least some mangabey groups' home ranges were never penetrated by neighbors. Playback tests with black-and-white colobus and blue monkeys, among which territorial spacing has been reported, indicate that responses to loud calls have some degree of site-specificity among these species. But the mangabey pattern of intergroup spacing appears to result from a combination of low group density, site attachment within groups, and site-independent avoidance between groups. These results emphasize that spacing "system" and "pattern" are not necessarily equivalent; a given set of spacing behaviors can result in different spacing patterns under different ecological conditions, while a given pattern may be obtained by any of several behavioral means. Evidence for site-independent spacing in other primate species is discussed.

The use of urine marking in the scavenging behavior of the red fox (Vulpes vulpes)

Abstract: The eleven different functions for which mammals use urine marking are reviewed in this paper, and the urine marking behavior of the red fox (Vulpes vulpes) is described in detail. A new hypothesis is advanced that urine marking may serve as a "book keeping system" in the red fox's scavenging behavior. Foxes consistently investigate and urine mark inedible food remnants (e.g., bones, bird wings, and dried out pieces of hide). When a fox re-investigates a marked remnant, the urine mark signals "no food present," and the fox investigates this object for only a brief period of time. This use of urine marking may increase the efficiency of its scavenging behavior, i.e. more food-items found per hour of scavenging. This efficiency may be particularly important during periods of food shortage. The hypothesis is tested in three different experiments, using free-ranging red foxes as subjects. Experiment I establishes that fox do urine mark food remnants. Experiment II shows that foxes investigate for a significantly shorter period of time (P<0.001) food remnants exhibiting both the odor of food and the odor of urine as compared to remnants exhibiting just the odor of food. Experiment III suggests that there a hierarchy of stimuli which determines different responses in the fox's scavenging behavior. The experiments also suggest that there is a degree of social behavior in the scavenging activities of red foxes. Foxes appear to use each other's urine marks to increase the efficiency of their scavenging behavior. Thus this study definitely support LEYHAUSEN'S (1965) statement that the social life of solitary animals is frequently more complex than we realize. Solitary species probably show many ingeniously adapted mechanisms for occupying niches where highly social species could not be maintained. The social evolution and ecological advantages of solitary species deserve to be the focus of future research.

Sexual Behaviour of the Female Laboratory Rat: Inventory, Patterning, and Measurement

Abstract: In this study some ethological principles were applied to a laboratory animal studied under laboratory conditions. The observations of the sexual behaviour of the female Wistar laboratory rat were performed in various behavioural contexts and under variable conditions. This made it possible to obtain detailed descriptions of some clear-cut behaviour elements, to determine the reliability of their identification, to analyze their interrelationships, and to study broader relationships of female sexual behaviour. Except for the transition from oestrus to dioestrus, attention was paid to all behavioural states of the female. Progressively, however, the study concentrated on the behaviour of females with reliable readiness to Lordotic Reaction. Observing the behaviour of such females shortly before and immediately after Lordotic Reaction resulted in the classification of the elements into three groups: Precopulatory Behaviour, Copulatory Behaviour and Postcopulatory Aversive Behaviour. The exhibition of Postcopulatory Aversive Behaviour means that the female after performing copulation is transitorily in an aversive state in which she reacts spontaneously or to the male's approach with specific defensive behaviour. Copulatory Behaviour of the female rat consists of Lordotic Reaction, usually accompanied by Ear-wiggling. The elements of Precopulatory Behaviour include Presenting Posture (usually accompanied by Ear-wiggling), Hopping (invariably terminated by Presenting Posture) and Darting (invariably terminated by Presenting Posture). In describing these elements the intensity dimension of their motoric performance was taken into account. The sufficient reliability of identification of the defined elements even in cases of their performance at low intensity, was demonstrated by means of the Kappa index. As soon as the female exhibits any Precopulatory Behaviour element her highest readiness to Lordotic Reaction can be expected. Darting can be considered as more intensive Precopulatory Behaviour than Hopping, and Hopping as more intensive than Presenting Posture. The last formulation is substantiated by three kinds of observations : (1) in the course of the natural oestrus first Presenting Posture, later Hopping and finally Darting emerge; (2) the stated order of intensity of Precopulatory Behaviour positively correlates with the amount of ovarian hormone doses injected to ovariectomized females; (3) Darting is the most effective, Hopping is moderately effective and Presenting Posture is little effective in inducing the copulatory activities of sexually inexperienced males. In addition, the following regularity should be mentioned: the more intensive Precopulatory Behaviour, the more probable is the occurrence of Postcopulatory Aversive Behaviour. Naturally as well as artificially oestrus females prefer to exhibit Precopulatory Behaviour of a certain intensity for some time. The endogenous determination apparently limits the potentialities of the external stimulation. The scaling of the sexual responsiveness into six degrees was based on this principle. The four constituent degrees are "clean" : at the Lordotic degree the female does not react to a stimulus from the part of the male by any Precopulatory Behaviour, however, she reacts by Lordotic Reaction to the male's mount. The next three degrees are defined by that element of Precopulatory Behaviour (Presenting Posture or Hopping or Darting) with which the female reacts exclusively or almost exclusively to all the stimuli produced by the approaching male. Two intermediate degrees are "mixed" (the degree of Presenting-and-Hopping and the degree of Hopping-and-Darting) : the female reacts intermittently with two elements of Precopulatory Behaviour apparently in dependency on the intensity of the external stimulation. For the assessment of the intensity of the female sexual responsiveness a testing procedure was constructed, involving a series of subtests and taken into account a broader behavioral context.

Recognition of Neighbors' Duets By Stripe-Backed Wrens Campylorhynchus Nuchalis

Abstract: Stable groups of stripe-backed wrens Campylorhynchus nuchalis occupy exclusive territories and perform stereotyped duets and choruses in the same contexts in which many individually territorial passerines sing. When duets are broadcast from a speaker just inside a group's territorial boundary, the principal pair in the subject group reacts much more strongly to playbacks of strangers' duets than neighbors' duets. In addition, they respond slightly more intensely to a neighbor's duet on the wrong side of the subject group's territory than to the same duet on the correct side of the territory. These results indicate that stripe-backed wrens can differentiate neighboring groups' duets and associate each with a customary direction. The duets of this species have nearly the same effects on territorial residents as do the advertising songs of passerines with individual territories.

A Statistical and Motivational Analysis of the Social Behaviors of the Male Laboratory Rat

Abstract: The behavior sequences of male rats during tests for isolation-induced fighting were analyzed by computer. All transitional dyads which were highly significant (probability less than .001 by chance) were listed in tables and categorized. Most highly significant transition dyads fell into five categories: exploration and scent-marking; grooming; defense and submission; offense, and approach and retreat. All of these categories were obtained for sequences within the home rat, within the intruder rat, and between the two rats except for the following: offense sequences were seen only in the home rat; approach and retreat sequences were seen only in interactions; and interaction sequences usually involved combinations of offense with defense or submission rather than simple offense sequences or simple defense-submission sequences. Further analysis of exploration and scent-marking dyads suggested that the various acts and postures all reflect a single underlying motivational mechanism which activates motor patterning mechanisms whose motor patterns are directed by continually changing orientation towards different objects in the environment. The ratios of obtained to expected frequency of transition from one act or posture to another were usually symmetrical and most of the possible dyads were observed in frequencies greater than expected by chance. Analysis of grooming dyads also suggested that these acts and postures reflect a single underlying motivational mechanism which activates motor patterning mechanisms through which directing stimuli orient grooming towards various parts of the animal's own body or the body of the opponent. Within self-grooming most of the possible dyads were observed at frequencies greater than expected by chance, and the transition ratios were symmetrical. It was suggested that these behaviors all facilitate the broadcast diffusion of odors from scent glands on the face, flank, and ano-genital region, that the motivational mechanism is activated by sensations arising from these glands which are differentially activated by way of other motivational mechanisms, and that self-grooming might also be characterized as "self-anointing". Offense behaviors of the home rat tended to follow an asymmetrical sequence: from sniff-dish and crawl-over-dish to repeated offensive sideways posture to full aggressive posture to bite-and-kick attack, with the latter act followed by a refractory period. The frequent initiation of the sequence by sniff-dish behavior was taken as evidence that an offense motivational mechanism is activated by comparison of strange rat odors with familiar home cage odors. A number of acts and postures were considered to be ambivalent or hybrids of motor patterns produced by patterning mechanisms simultaneously activated by offense and other motivational mechanisms. These include aggressive groom and rub (grooming and offense), crawl-under (exploration and offense), and offensive sidoeways posture, upright posture and boxing (both offense and defense). A detailed analysis of the many dyads from offense behavior to defense and submissive behaviors led to the following hypothesis. There are probably two different motivational mechanisms, defense and submission, which are activated by stimuli associated with attack by the opponent, dorsal tactile stimulation or an elevated approach. Both defense and submission are elicited by dorsal tactile stimulation and both are potentiated following subjection to attack. Defense, but not submission, may also be elicited by a high approach of the opponent. The motor patterns of defense are flight in a large enclosure, or high postures in a confined space. The high postures are usually of low intensity (sideways posture) if the motivating stimuli are of low intensity and if the motivational mechanism is not sensitized by previous attack. They are usually of high intensity (upright postures) if the motivating stimuli are of high intensity or if the motivational mechanisms has been sensitized by attack. The submissive postures may also be of low intensity (crouch) or high intensity (full submissive posture) depending upon intensity of motivating stimuli and sensitization by pain. Submission often includes the emission of a 25 kilo herz ultrasound cry which inhibits further attack by the opponent. An alternative hypothesis was considered: that submission and defense are sets of motor patterning mechanisms, each activated by a single motivation mechanism but differentiated by different releasing stimuli. In addition to the primary significant transitional dyads mediated by five motivational mechanisms, there were also many secondary and tertiary transitional dyads obtained as a result of the temporal correspondence of two different acts or postures each elicited as primary effects from another behavioral act or posture which preceded both of them. These secondary and tertiary effects, less significant than the primary effects, could be demonstrated by triangulation in flowcharts of the behaviors. Practically all of the 105 highly significant behavioral transition dyads in the tests could be explained as primary effects due to the action of only five basic motivational mechanisms and the secondary or tertiary effects based on these primary effects. The five motivational mechanisms were identified as: exploration and scent-marking; grooming, offense; defense; and submission. A model was presented which included these five motivational mechanisms, their critical stimulus inputs (motivational stimuli), the motor patterning mechanisms which they activate and which receive separate input from releasing and directing stimuli. Specific acts and postures could be understood as simple or complex combinations of motor patterns which were produced by motor patterning mechanisms activated by single or multiple combinations of motivational mechanisms.

Search Behaviour: a Study of Three Caterpillar Species

Abstract: 1 The searching behaviour of three species of caterpillar-Pievis rapae L, Plusia californica Speyer, and Plutella maculipennis (Curt)-has been described and the descriptions incorporated into simulation models 2 Canadian P rapae were studied in most detail Their behaviour changes with hunger When replete, a larva moves slowly, turns often, and 'head-waves' frequently As it becomes hungrier, it speeds up, straightens out, and stops head-waving At the same time, the distance from which it can perceive a host plant decreases All these changes can be temporarily reversed by allowing the caterpillar to contact (but not necessarily feed on) a host plant The rate at which the changes occur is temperature-dependent 3 Simulation of these search patterns shows that the replete behaviour (called 'conservative search') is appropriate to searching within a small clump of plants, whereas the later behaviour ('radical search') is appropriate to random or uniform distributions and low plant densities 4 Australian P rapae showed the same pattern of behaviour, but the changes were less pronounced They neither began their search as conservatively, nor adopted such radical search patterns later 5 Neither Plusia californica nor Plutella maculipennis show substantial changes in behaviour as they starve Plusia always travels rapidly and with a moderate amount of head-waving It turns infrequently and has a tendency to zig-zag Thus it uses radical search from the beginning Plutella is just the opposite It moves slowly, head-waves frequently, and turns often; it maintains this conservative search pattern throughout 6 The relationship of these species' behaviour to the distribution of their host plants is discussed P rapae and Plutella both feed on cruciferous plants, which tend to occur in small clumps where conservative search is appropriate behaviour (Plutella's failure to change its behaviour if unsuccessful may be related to its relatively low voracity and to the timing of its life cycle) Plusia is polyphagous, so its resources are distributed less contagiously, and radical search is appropriate behaviour 7 Other circumstances where the different types of search are appropriate behaviour are discussed

Copulatory Behavior of Golden Hamsters (Mesocricet Us Auratus)

Abstract: Several experiments were performed in order to provide quantitative and qualitative descriptions of the copulatory behavior of syrian golden hamsters (Mesocricetits auratus) observed under laboratory conditions. The results of these studies indicate that: I. The male copulatory pattern may be generally classified as a multiple intromission, multiple ejaculation pattern with no copulatory lock and an absence of thrusting during intromission. The exception to this is the appearance of "long" intromissions, involving multiple intravaginal thrusting, as the male approaches satiety. The function of the long intromission appears to be to increase penile stimulation in the male. Significance of the long intromission for the female is unknown. 2. Behavioral criteria which allow ejaculations to be distinguished from other complete intromissions were identified. The most valid criterion was an increase in rate of preinsertion thrusting prior to ejaculation. It was also possible to use behavioral measures to identify the post ejaculatory interval. 3. Data from standard latency and frequency measures were quite similar with those of BEACH & RABEDEAU (1959). There was, however, an increase in ejaculation latencies and interintromission intervals as the male approached the satiety criterion. 4. The duration of intromissions during which ejaculations occurred was reliably, but not strikingly, longer than that of non-ejaculatory "regular" intromissions. The durations of "long" intromissions, during which no ejaculations were ever found to occur, generally exceeded the duration of both ejaculations and regular intromissions, but some overlap existed. "Long" intromissions could, however, be identified by multiple intravaginal thrusting behavior. In the first copulatory of a test, the first intromission was of longer duration than later intromissions. 5. Male golden hamsters exhibit renewed copulatory behavior after reaching satiation if another, previously unmated female is introduced into the test situation (Coolidge Effect). Female contributions to the regulation of satiety effects appeared to be extensive but were not analyzed in the present study. 6. In contrast to many other rodents, male behavior of golden hamsters is exceptionally channelized toward copulatory behavior during the ejaculation latency period. Also, in contrast to many other rodents, the duration of lordosis in female golden hamsters is very long. Other species typical differences were also observed.

The Behaviour of Mongolian Gerbils in a Semi-Natural Environment, With Special Reference To Ventral Marking, Dominance and Sociability

Abstract: We observed the behaviour of a colony of Mongolian gerbils (Meriones unguiculatlts) for 18 weeks, in an enclosure provided with facilities for burrowing, nest-building, foraging, wheel-running and other behaviour. Records were taken of both social and individual activities, and in particular of activities occurring during encounters between pairs of individuals. I. The colony originally consisted of eight animals, but severe fighting rapidly reduced the numbers to two males and two females. The colony then remained stable until week 18, when an adult male attacked the offspring of one of the females. Fighting was never observed between animals of opposite sex. The fighting was probably due to overcrowding, and suggests that in natural conditions gerbils do not nest in groups of more than a few adults. 2. Routine encounters between individuals revealed a number of sex differences, but few conspicuous individual differences. Agonistic behaviour was rare, and the observations gave little evidence for the existence of a dominance order. 3. When a female was in oestrus one male consistently attacked and chased the other, and consequently gained almost exclusive access to the female. The sequence of mating responses is described, and it is suggested that genital sniffing by the male enhances the receptivity of the female. Ventral marking by the female and drumming by the male occurred at unusually high levels during mating. 4. Each female produced two litters, but only the first two survived. The litters were dropped and the young housed in a nest-box outside the normal colony burrow, the entrance to which was kept blocked. Both litters were carried to another nest-box in the second week after parturition, and carried back again prior to the birth of the second litters, but the reasons for this behaviour were unclear. The males assisted in nest-building activities, but never entered the maternal nest-box. We suggest that the failure of the females to care for their second litters was due to overcrowding. 5. Ventral marking occurred at a high rate, and in conjunction with various activities. Marks were deposited over the entire enclosure and on a variety of substrates, but were concentrated at four main sites on mounds of earth near the burrow. There were no sex differences in total number of marks, but the males tended to distribute their marks more widely. Individual differences in amount of marking were correlated with differences in gland size, and with the outcome of aggressive encounters during mating and the occasional fighting. There was a strong tendency for fresh marks to elicit counter-marking by the same or another animal, but novel clean objects were also marked within a short time of being placed in the colony. There was no evidence that marked objects or areas were avoided by other animals or defended by the marker, and we suggest that marking is not primarily territorial in function. 6. Mutual marking, mutual grooming and sandbathing all occurred at the four most heavily marked sites near the burrow. We suggest that these activities, and the tendency for animals to counter-mark at specific sites, might serve to distribute a colony odour consisting of the odors of the individuals, and that this might reduce intra-colony aggression. We found no evidence that mutual marking or grooming reflected a dominance order. Drumming of the substrate occurred as an alarm response, but we saw no evidence of its use as an alarm signal. 7. The most frequent individual activity was digging. The burrow, which was inhabited by all the adults, consisted of from two to eight tunnels leading in towards a central nest of shredded paper, straw and leaves. The tunnels were repeatedly cleared and enlarged, and were often destroyed by digging at other locations. Freshly dug earth was often marked by the digger, and this seemed to elicit marking and digging by other animals. 8. Wheel running occurred only at a low rate, and did not develop a stereotyped character, but was performed by all animals. Contrary to expectations based on laboratory studies the majority of running occurred during the light phase of the cycle, and this was when the animals were most often active in the general sense. We suggest that gerbils are probably active day and night in natural conditions, and that the enhanced nocturnality shown in laboratory studies may be due to the lack of a dark burrow. 9. Other stereotyped activities such as shredding paper, gnawing and scrabbling were rare. 10. The results are summarized and discussed in relation to theories of dominance, ventral marking and sociability, and attention is drawn to the need for more field studies of behaviour in this species.

An Analysis of the Temporal Patterning of Pecking in Chicks

Abstract: In this paper aspects of the temporal and sequential patterning of pecks in the domestic chick are examined. To this end experiments were done in which young chicks were allowed to peck at pairs of coloured stimuli - the time of each peck being recorded automatically by a small computer. A particularly striking feature of the chicks' behaviour was the tendency of the pecks to occur in rapid bursts. Such bouts have been described (and quantified) for behaviours in a number of species, but the bout itself has proven to be a particularly difficult unit to define empirically. Accordingly a model is proposed which describes the order independent features of the intervals between pecks, and also objectively defines a bout criterion interval. This model assumes that not only do pecks tend to cluster into bouts but that the bouts themselves occur in clusters. Consequently two types of between bout intervals will be generated: "not pecking" intervals, whose mean length is long, and which separate bout clusters; and intervals of medium average length, separating bouts within a cluster. It is assumed that these between bout intervals are generated by two random (Poisson) processes of sharply differing rate constants. To test this model an Algol procedure was written which describes the survivorship curve of intervals between pecks in terms of components that can be adequately characterized as negative exponential. It is found that with large sample sizes three distributions are consistently delineated; the "not pecking" intervals are characterized by an exponential with a rate constant of order 10 -3 , the intervals within a cluster by one of 10 -2 and the within bout intervals by one of 10 -1 (if the latter generating process is assumed to have a dead time). In addition, a stable bout criterion ranging from 1.9 to 2.3 secs is defined. It is also argued that degeneracies in this model can occur when sample sizes are small - in particular that the intervals of medium length are either not distinguished from those belonging to the outer state of long intervals, or fail to be completely delineated from the two other components. Part II of this paper examines additional features of the pecking behaviour within the framework of this model. The question of how a colour is preferred is explored and it is found that preferred colours in these experiments receive from 1.6 to 3.2 times as many bouts, which are on average 1.1 to 1.3 times as long as those directed at the less preferred colour. Some information on sequencing of bouts is presented in which it is shown that there is a probability of about .60 of continuing to "bout" at the same position when the two stimuli are the same colour. This finding is combined with a measure of overall colour preference to allow fairly consistent predictions of the transition probabilities between bouts when the stimuli differ in colour. Upon examining the intervals within a bout it is found that although they peak strongly at .3 secs they can range between .1 and 2.3 secs. Through indirect evidence it is argued that the number of pecks within a bout also varies substantially. However, it is found that the distribution of intervals within a bout remains nearly invariant regardless of what colours the chicks are pecking. It is suggested that this invariance provides some objective verification for the concept of a "bout unit". However, upon closer examination, differences in the distribution of within bout intervals are found. These differences are interpreted as resulting from the rather surprising occurrence of mixed bouts, that is bouts during which pecks were elicited by both stimuli. Intervals within such mixed bouts were on average longer than those occurring in bouts where all pecks were directed at the same stimulus and consequently effected shifts in the mean and increased the spread in some of the within bout interval distributions. It is tentatively suggested that such mixed bouts are elicited when the chicks attend to cues upon which the stimuli cannot be distinguished. An important assumption of the model is that the interval distributions arising from the three generating processes overlap and that while a stable and obj ective bout criterion can be defined it does not provide a neat means of classifying intervals into either within or between bout intervals. Some intervals less than the bout criterion are assumed to belong to the processes generating between bout intervals. For this reason the total number of bouts defined by the criterion interval will underestimate the true number of bouts occurring - some bouts will be merged together when one of these very short between bout intervals occurs. The occurrence of mixed bouts, along with the substantial proportion of undetectable between bout intervals is shown to hinder extensive examination of the properties of the bouts defined by the criterion interval; it is argued that considerable ambiguity exists in the bouts so defined. The origin of this ambiguity is discussed within the framework of current studies in which bouts of behaviour, defined by a criterion interval, are used as a basic analytical unit.

Social and Individual Behaviors in Captive Slow Lorises

Abstract: Two groups of wild-born slow lorises were housed together in a semi-natural laboratory environment for 20 weeks. The animals are nocturnal and were observed under dim red illumination by means of a low-light TV camera. The behavior of each animal was videotaped for 5 consecutive minutes 3 times a week. Then, written records were obtained of everything that the animal did or had done to it, moment by moment, as well as the time spent on each activity. Analyses were carried out to determine: which behaviors accounted for the majority of time and frequency scores, how behavior changed over time, and what were the dynamics of within-group interaction. The most striking finding was the degree of sociability found to exist among adult slow lorises. Once they had become familiar with one another, they approached each other often but seldom left during an ongoing interaction, spent much time sitting in proximity to one or more others or in passive contact, social groomed and play-fought. Agonistic behavior was infrequent and did not have serious consequences. The tendency to interact in predominantly friendly ways with others was true of all individuals in a group. These findings were surprising because nocturnal prosimians once were believed to be relatively solitary. However, the present results are in keeping with those of recent field reports on other, related species. It is apparent that the old view of nocturnal prosimians is in need of some revision.

Wolf spider sociobiology: I. Agonistic display and dominance-subordinance relations in adult male Schizocosa crassipes.

Abstract: 1. Agonistic display among adult male Schizocosa crassipes (Walckenaer), the brush-legged wolf spider, was described. These stereotyped displays are observed exclusively during male-male encounters. 2. The presence of conspicuous black tibial brushes on the males' forelegs, coupled with movements and/or postures of the forelegs, suggests a visually-mediated communication system. 3. R-type factor analysis of the agonistic behaviors treated as variables resulted in four factors which accounted for 74.3% of the variance. These factors were interpreted as "Approach/Signal", "Vigorous Pursuit", "Run/Retreat" and "Non-Linking" behaviors. A transition probability matrix of inter-individual behavior sequences allowed determination of which behaviors followed one another beyond chance levels. 4. Agonistic displays were graded on an Approach-Avoidance continuum and weighted from + 1 to +5 for approach behaviors and -1 to -5 for avoidance behaviors. The factor analysis of the behaviors and transition probability matrix served as guides for determining intensity weights for each agonistic behavior, and a Dominance Index (DI) was calculated for each spider with every partner. 5. Each spider was classed as Dominant, Intermediate or Subordinate on the basis of its DI and the number of spiders present in the test group, and a stable, linear dominance hierarchy was observed over 10 days. 6. Q-type factor analysis of the subjects treated as variables resulted in four factors accounting for 90.0% of the variance. The first two factors explained 83.3% of the variance, and were interpreted as "Subordinance" and "Dominance" on the basis of the DI's of those spiders comprising each factor. 7. Multiple stepwise discriminant analysis verified the three dominance categories and revealed differences among the groups on the basis of the kinds and frequencies of agonistic display. Dominant spiders exhibited Approach/Signal and Vigorous Pursuit behaviors; Subordinate spiders exhibited Run/Retreat behaviors; and Intermediate spiders exhibited Run, Retreat, Contact, Tapping, and approach-oriented behaviors. 8. Agonistic display in S. crassipes is a complex male-male communication system which may serve as a behavioral mechanism for preserving personal space among con-specifics, and for maximizing the chances of Dominant males mating.

Mixed Song, Interspecific Competition and Hybridisation in the Reed and Marsh Warblers (Acrocephalus Scirpaceus and Palustris)

Abstract: [1) Three Reed Warblers (Acrocephalus scirpaceus) with a mixed scirpaceus-palustris song, settled into the dry habitat of a Marsh Warbler (A. palustris) colony in the Liege Province of eastern Belgium in 1974 and 1975. One was established in a mixed population of Reed and Marsh Warblers, and the other two, whose songs were extensively tape-recorded, defended territories inside a large population of Marsh Warblers. 2) The mixed songs consisted of a succession of rather short fragments of song of both species, directly juxtaposed. The palustris phrases contrasted with the scirpaceus phrases not only by their highly mimetic nature, but also in their more liquid timbre, more rapid delivery and rhythmic characteristics. In both mixed singers established in the large Marsh Warbler colony, the palustris song occupied longer sequences and was thus predominant over the scirpaceus element. 3) Observation and playback experiments showed that the mixed songs provoked reactions by individuals of both species, and the Reed Warbler mixed singers reacted to the normal song of both species. But Reed and Marsh Warblers with normal songs reacted only to the song of their own species. Various considerations suggest that the mixed singers had probably learnt the song of the Marsh Warbler during their postfledging period. 4) A Reed Warbler mixed singer, established in the colony in 1975, paired with a female Marsh Warbler. The breeding cycle of the mixed pair proceeded normally until both parents abandoned the nestlings at six days old. This was apparently the result of food shortage during a period of very unfavourable weather, which also affected a large proportion of the breeding pairs of Marsh Warbler. 5) Hybridisation is most easily explained by assuming that the female was as attracted by the mixed song as by the normal song of her own species, given that the territorial male Marsh Warblers reacted strongly to it. The close similarities in the breeding behaviour of both species are discussed, as well as the considerable overlap in ecological requirements. Comparative studies of mixed breeding populations are needed to evaluate the degree of inter-specific competition, and to detect more possible cases of mixed song and hybridisation., 1) Three Reed Warblers (Acrocephalus scirpaceus) with a mixed scirpaceus-palustris song, settled into the dry habitat of a Marsh Warbler (A. palustris) colony in the Liege Province of eastern Belgium in 1974 and 1975. One was established in a mixed population of Reed and Marsh Warblers, and the other two, whose songs were extensively tape-recorded, defended territories inside a large population of Marsh Warblers. 2) The mixed songs consisted of a succession of rather short fragments of song of both species, directly juxtaposed. The palustris phrases contrasted with the scirpaceus phrases not only by their highly mimetic nature, but also in their more liquid timbre, more rapid delivery and rhythmic characteristics. In both mixed singers established in the large Marsh Warbler colony, the palustris song occupied longer sequences and was thus predominant over the scirpaceus element. 3) Observation and playback experiments showed that the mixed songs provoked reactions by individuals of both species, and the Reed Warbler mixed singers reacted to the normal song of both species. But Reed and Marsh Warblers with normal songs reacted only to the song of their own species. Various considerations suggest that the mixed singers had probably learnt the song of the Marsh Warbler during their postfledging period. 4) A Reed Warbler mixed singer, established in the colony in 1975, paired with a female Marsh Warbler. The breeding cycle of the mixed pair proceeded normally until both parents abandoned the nestlings at six days old. This was apparently the result of food shortage during a period of very unfavourable weather, which also affected a large proportion of the breeding pairs of Marsh Warbler. 5) Hybridisation is most easily explained by assuming that the female was as attracted by the mixed song as by the normal song of her own species, given that the territorial male Marsh Warblers reacted strongly to it. The close similarities in the breeding behaviour of both species are discussed, as well as the considerable overlap in ecological requirements. Comparative studies of mixed breeding populations are needed to evaluate the degree of inter-specific competition, and to detect more possible cases of mixed song and hybridisation.]

The Solution of Patterned String Problems By Birds

Abstract: 1. Three budgerigars quickly learned to pull to their cage a 15 cm long black string to which a small food container was attached. Then two strings of the same length but of different colour were offered, one of which was cosmected with a food container. One budgerigar learned successively with significant percentages of correct choices to pull the string with the container when both strings were arranged in one of 7 different patterns (Fig. 2 A-G). The bird mastered 2 of these arrangements spontaneously. Finally the budgerigar chose correctly in significant percentages of choices when 4 of these tasks were offered in predetermined irregular sequence in series of 30 trials. In these cases also the colours of the strings, the position of the correct string to the right or to the left, and the normal or the reflected arrangement changed in predetermined, irregular succession. These continuously changing situations always required different associative processes and new decisions. A second budgerigar mastered such tasks only when not more than string patterns were offered in irregular sequence. A third budgerigar learned to choose the correct string only when one of the simple string patterns A, B or C was offered in a series of trials. An Indian starling (Acridotheres tristis) and a jackdaw (Coloeus monedula) quickly learned to pull a string with a food container, but proved to be inappropriate for experiments with two strings because the handling of the strings in itself appeared rewarding to them. 2. The results of these experiments confirm that the brain achievements of birds are not inferior to those of mammals, although their forebrain lacks a cortex with several layers of neurons. They support the hypothesis that the specific configuration of forebrain regions is less important for more difficult brain achievements than the number and differentiation of neurons and the number of synapses.

A Longditudinal Study of Mother-Young Interaction in the Rat: the Effects of Infantile Stimulation, Diurnal Rhythms, and Pup Maturation

Abstract: Rat litters had either pups and mother handled (LH), mother only handled (MH), or were left undisturbed (NH), in two sessions per day from birth to weaning. They were observed throughout this period. Recordings were made hourly, and also at 3 minute intervals for an hour before and an hour after each treatment. Diurnal rhythms and maturational changes were catalogued. Treatment interacted with these factors; overall it had deleterious consequences for the quality of maternal care as measured by nursing behaviour, nest building, and the quality of the pup environment. Some changes, notably in nest building, were specific to LH, but generally LH and MH showed similar trends with more marked effects in MH. As adult open-field testing showed LH offspring to ambulate significantly more than MH or NH no clear support is found for maternal mediation of infantile stimulation.

The Patterning of Preening and Other Comfort Behaviour in a Herring Gull

Abstract: The patterning of body-care behaviour in the Herring Gull has been studied by means of: (a) qualitative observations on four individuals, and (b) application of six quantitative analytical methods on the behaviour recordings of the dominant gull (which was least influenced by other individuals). The qualitative observations led to the conclusion that in a body-care sequence a number of sharp behaviour switches occur in a fixed order; between successive switches the following "main components" could occur: bathing, shaking, oiling, and preening. The quantitative methods with their results can be recapitulated as follows: 1. An analysis of frequencies of the different behaviour elements suggested that within the "main components" these frequencies tended to change gradually over time. 2. The distributions of the behaviour elements were further studied by means of the temporal relations between events of the same element. This analysis revealed that each element occurred in "bouts", which could be interspersed with events of other elements. 3. It was also studied whether different elements had similar distributions over the observation time. This method was concentrated on the behaviour during short intervals between events of the same element; its results indicated that different elements had different distributions over time, although these distributions could be partially overlapping. 4. The sequential patterning of these different frequency distributions was studied in detail by measuring the interval durations between events of different elements. The results of these four analytical methods could be explained by postulating a programme for sequencing and/or timing of smooth changes in the probabilities of occurrence of the different behaviour elements within each "main component". 5. By means of transition analysis it was investigated whether apart from the slow frequency changes, rapid processes also played a role. Because of differences between reciprocal transitions, it was concluded that those rapid processes were important too. 6. From the frequencies of the combinations between movements and the places to which they were directed, a certain amount of dependence between the components of separate behaviour events could be proved. The results of this study have been discussed in relation to Van lersel & Bol's study on preening in terns. It was argued that their threshold model was too simple for a satisfactory explanation of the patterning of body-care behaviour. The discussion of the present results in relation to hierachical models was more successful. The mechanism underlying body-care behaviour can be considered as a programme with a main routine (order of main components) and several sub-routines. The role of state variables in this programme has been illustrated in two diagrams.

The Ontogeny of Predatory Behaviour in the Golden Hamster (Mesocricetus a. Auratus)

Abstract: The study set out to examine the ontogeny of the predatory response in golden hamsters (M. a. auratus) towards nymphs of Locusta migratoria. Qualitative and quantitative observations were reported. Qualitative observations showed that ambivalence characterized the behaviour of a naive hamster during the initial encounters with prey. Repeated bouts of prey exploration followed by rapid withdrawal occurred. Eventually with repeated prey presentations ambivalence waned and capture was attempted by nipping, seizing and grasping with the forepaws. Occasionally the prey was pouched after capture or 'carried' for a short duration. Consumption of the prey following capture invariably occurred. Quantitative data was collected from four age groups ranging from 30 to 90 days of age. The basic methodology consisted of introducing prey into the home cage of a naive subject and manually recording the following behaviours: latency to capture, and the frequency of prey exploration, withdrawal from the prey, nip at the prey and unsuccessful capture. Repeated tests for prey capture were administered and the main findings showed: 1. Older hamsters were more likely to capture; 2. Hamsters became more efficient captors after experiencing several successful captures; 3. Marginal differences between the sexes; 4. An increase in (a) the amount of prey eaten, (b) the frequency of pouching after capture, (c) carrying after capture with repeated testing. The mechanisms postulated to account for the increase in probability and efficiency of capture were: a. Fear attenuation through the process of habituation. b. Practice of the prey-capture technique. c. Development of a learnt appetite for the prey. It was concluded that prey-capture in the hamster was a species-typical behaviour founded upon innate predispositions.

On Assessing the Bases of Partner Preferences

Abstract: If individual X spends more time with A than with B, is it because X approaches A more than he approaches B, or because he avoids A less than he avoids B, or because A approaches X more than B approaches X, or A avoids X less than B avoids X? Or is it due to some combination of these possibilities ? A method for discriminating between these possibilities is presented and discussed.

Play and Socio-Sexual Behaviour in a Captive Chimpanzee (Pan Troglodytes) Group

Abstract: 1. Play and socio-sexual behaviors were studied in a captive chimpanzee group composed of three mothers and their offspring. 2. Mother-other infant relationships were more extensive and varied than those reported among wild chimpanzees. These relationships did not affect the motherinf ant bond. 3. Socio-sexual behaviors were regularly directed toward infants by all group members, including other infants. It is suggested that infant socio-sexuality should be viewed not only as a developmental phenomenon, but as an important factor in group interaction patterns. 4. Group play centered around the oldest male infant and two mothers played more with other infants than with their own infants. 5. Patterns of interaction among group members were shown to be heavily dependent on age-sex status. 6. Young infants initially tried to behave toward one another much as they behaved toward their own mothers. The way in which this tendency produced entirely new behavior patterns is discussed.

Variable and Constant Structures in Greenfinch Songs (Chloris Chloris) in Different Locations

Abstract: For greenfinches, songs from different places in Europe have been studied. It has been determined which characteristics are constant (typical for all songs) and which are variable (typical for one place only). The song of greenfinches is not stereotyped: a given song element may be followed alternately by different element types. Within a breeding area most males sing the same element types. The following general features are characteristic for all songs studied: 1) size of the repertoire (30 - 35 different element types); 2) the general shape of the elements (four basic patterns, the four classes of element types, were found in all locations; 3) syntax feature (length and temporal pattern of "tour"). The exact shape of the elements is variable. These details are modified by learning. Song elements from different breeding areas show different rising or falling frequencies. The divergence in the morphology of the elements does not increase with increasing distance. Thus the capacity to alter the basic element pattern is very limited.

Changes in the Relationships of Captive Rhesus Monkeys On Giving Birth

Abstract: I) Relationships between captive adult female rhesus monkeys were assessed for 6 weeks before and 20 weeks after birth in terms of proximity, approaches and leavings, grooming and agonistic interactions. 2) Before the births, the mothers-to-be spent more time with (and more time grooming with) related than with unrelated individuals. Responsibility for proximity with unrelated adult females to whom the mother was dominant lay primarily with the mother, but where the other female was subordinate it might lie with either party. Mothers-to-be tended to groom adult females dominant to themselves more than they were groomed by them, and vice versa. 3) Differences between the times that mothers-to-be spent near members of different age/sex/rank classes could not be accounted for in terms of generalizations describing preferences of the mothers for members of those classes nor relative preferences of them for her. 4) After the births, members of all age/sex/rank classes tended to be near (and to groom) mothers more when the infants were on the mothers than when they were off but near her, and to be near the mother more when the infants were off but near than when the infants were off and distant from the mother. Proximity between mother and others tended to become more independent of the position of the baby as it developed. 5) Differences between age/sex/rank classes in time spent near the mother after birth were generally similar to those found before birth. The index for the mother's role in maintaining proximity was predominantly negative. 6) All age/sex/rank categories tended to be near the mother less after the birth than before, especially when the infant was off its mother. The differences disappeared with time. Adult males tended to groom the mother less, and adult females to groom her more, than before birth. 7) Changes in proximity between mother and other from before to after birth can be understood in terms of an increase in the attraction of others to mother and a decrease in mothers' affinity for others.

Catatonic behaviour in the Norway rat.

Abstract: Different forms of catatonic behaviour occurring spontaneously as fright reactions in wild and laboratory Norway rat are described. In wild rats, the catatonic reaction appears in form of stupour. The frequency of this phenomenon in the 5th generation of out-bred vivarium population of wild rats is 20%, the stupour being represented by a "rearing" (10%) or "hanging" (10%) form. The threshold of this reaction is especially low in females. Predisposition to the stupour is hereditary; the mode of inheritance of this feature seems to be complex. In laboratory albino strains of rats, such akinetic form of catatonic reaction is rare (no more than 1%), but hyperkinetic phenomena in form of pendulum movements are common. These pendulum movements show a positive genotypical correlation with the predisposition to audiogenic seizures and a negative genotypical correlation with the vegetative component of emotionality. No influence of sex on the expression of pendulum movements was found. A hybridological analysis demonstrated that the predisposition to pendulum movements is linked to the inhibition of eumelanine synthesis in cc or pp homozygotes. In AUG/WAG or AUG/SD hybrids with normal eumelanine synthesis there are neither pendulum movements nor the stupour like that in wild rats; however, about 30% of them show an expressed akinetic reaction in form of freezing when placed into a strange environment. The relation of catatonic reactions to normal and pathological behaviour, and the possibility of using catatonic strains of rats as ethological models of schizophrenia are discussed.

Wolf Spider Sociobiology: Ii. Density Parameters Influencing Agonistic Behavior in Schizocosa Crassipes

Abstract: 1. The influences of social, spatial and population density parameters on agonistic behavior in the adult male wolf spider Schizocosa crassipes were analyzed. Social density varied the number of spiders present (N = 2, 3 or 5) in different spatial densities (U =90, 180, 270 or 450 cm 2 ). Population density varied the amount of space available per animal, irrespective of social and spatial density. 2. Multiple stepwise discriminant analysis revealed differences among the social, spatial and population density groups on the basis of the number and kinds of agonistic behaviors displayed. 3. As social density increased, the number of agonistic interactions increased. Although the spiders did not interact more frequently with any one partner over 10 days, they continued to respond differentially to one another with regard to established dominance-subordinance relations. 4. Within each spatial density, the amount of space had no effect on the total number of agonistic interactions. However, within each social density, the number of agonistic interactions varied according to the amount of space available. In less restricted spatial densities, agonistic interactions increased with the number of spiders. 5. The absolute distance maintained between spiders increased proportionally with spatial density. However, when distances were expressed as a percentage of the maximum possible distance between any two animals, spiders tested in the largest spatial density exhibited decreasing inter-individual distances over time, while those tested in the smallest spatial density exhibited increasing distances. These findings suggested social attraction among the spiders when sufficient space was available. 6. As population density increased the number of agonistic interactions increased. However, no differences in the number of interactions between specific partners occurred. 7. By comparing Equal and Low population density groups, an estimate of the personal space of male S. crassipes was calculated to be 5.35 cm, which agreed with field and laboratory observations. 8. When spiders are grouped within certain spatial limits, various types of agonistic behaviors serve to space the animals according to their personal distance. High population density may interfere with communicatory behavior patterns which in turn may weaken dominance-subordinance relationships.

Brood and Crèche Stability in the Common Eider of the St. Lawrence Estuary

Abstract: [The nature and duration of the parental bond in the Common Eider (Somateria mollissima) of the St. Lawrence estuary was studied using 1400 individually tagged females. Several degrees of broodiness were recognized in birds tending broods and/or creches. Four behavioural categories (B-, A-, V- and N) based on this variability were substituted in lieu of the vague term "aunts" used in previous literature. Eiders of the St. Lawrence estuary did develop a stable and exclusive parental-type bond with all the ducklings they accompanied. Even groups (creches) of 15-35 ducklings led by one, or sometimes two B-status females did function as family groups (one B-female and 3-5 ducklings) and displayed great cohesiveness after the ducklings reached a certain age (about one week). The minimum duration of the parental-type bond was estimated at 40 days. Some European workers have suggested that creching is of greater survival value for adult females than for ducklings, allowing females exhausted by incubation to move rapidly to better feeding grounds. Consequently, the link between any female and a creche was seen as transitory. These views are rejected on the basis of evidence collected in the present work., The nature and duration of the parental bond in the Common Eider (Somateria mollissima) of the St. Lawrence estuary was studied using 1400 individually tagged females. Several degrees of broodiness were recognized in birds tending broods and/or creches. Four behavioural categories (B-, A-, V- and N) based on this variability were substituted in lieu of the vague term "aunts" used in previous literature. Eiders of the St. Lawrence estuary did develop a stable and exclusive parental-type bond with all the ducklings they accompanied. Even groups (creches) of 15-35 ducklings led by one, or sometimes two B-status females did function as family groups (one B-female and 3-5 ducklings) and displayed great cohesiveness after the ducklings reached a certain age (about one week). The minimum duration of the parental-type bond was estimated at 40 days. Some European workers have suggested that creching is of greater survival value for adult females than for ducklings, allowing females exhausted by incubation to move rapidly to better feeding grounds. Consequently, the link between any female and a creche was seen as transitory. These views are rejected on the basis of evidence collected in the present work.]

Markovian Versus Rhomboidal Patterning in the Song of Swainson's Thrush

Abstract: 1. This paper examines a claim of NELSON (1973) of rhomboidal patterning in the songs of Swainson's Thrushes reflecting supposed holistic control of the sequences. 2. The subjects were six Swainson's Thrushes recorded in the wild in Quebec. Samples from the six birds ranged from 40 to 346 songs. 3. We used a Ubiquitous Spectrum Analyzer, and Sonagraph to produce frequency-time displays, and the former to produce also amplitude-frequency spectra. 4. The songs consist of 5 to 7 consecutive syllables given in fixed sequence, except for occasional errors. Each bird had 3 to 7 song types, or particular sequences of syllables, also sung in fixed order. 5. Similar syllables may occur in different songs of individual birds. No convincing evidence of "recombination units" of syllable pairs was found. 6. Evidence essential to support the claim of rhomboidal pattern was found wanting. In particular a) the frequencies (pitches) of successive syllables do not fit a pentatonic scale; b) the validity of a keynote is doubted; c) the definition of rhomboidal patterning is so vague that even pseudorandom numbers yield results similar to those claimed for the thrushes. 7. Alternatively the Markovian model of sequences of events appears more suited to the songs of Swainson's Thrushes, based on the evidence of sequences of syllables and songs, and errors in these sequences.

Sex Differences in Behavior in a Group of Captive Juvenile Talapoin Monkeys (Miopithecus Talapoin)

Abstract: Previous laboratory studies have indicated that adult talapoin monkeys show sex differences in behavior which contrast with those observed in most other species of Cercopithecinae. The present study examines sex differences in a group of seven captive juvenile talapoins. Juvenile males were more active, less affiliative, more assertive, and more playful than females. They initiated and participated in all major types of social play, were avoided, and were alone more often than females. Juvenile females were more evasive, less playful, more affiliative, and showed more pronounced preferences for partners of their own sex than did males. Females avoided more often than males and avoided males more often than females. They groomed, were in proximity, and in contact more often than males, and performed these behaviors more frequently with females than with males. These characteristics have also been demonstrated in other juvenile monkeys. They occur in species with high degrees of adult morphological dimorphism where they are in accord with adult behavioral differences. They are also found in squirrel monkeys with low dimorphism and adult differences similar to those in talapoins, and in human beings. Thus they are not necessarily predictive of adult behavioral sexual dimorphism.

Social and Individual Behaviors in Captive Greater Galagos

Abstract: Two groups of wild-born greater galagos were housed in a semi-natural laboratory environment for 20 weeks. The animals are nocturnal and were observed under dim red illumination by means of a low-light TV camera. The behavior of each animal was videotaped for five consecutive minutes three times a week. Then written records were obtained of everything that the animal did or had done to it, moment by moment, as well as the time spent on each activity. Analyses were carried out to determine: which behaviors accounted for the majority of time and frequency scores, how behavior changed over time, and what were the dynamics of within-group interaction. Adult greater galagos were found to have only a limited capacity for establishing social bonds with strangers. Serious fights were infrequent after the first week, but throughout the study animals tended to spend the majority of their waking time away from others, often left immediately when approached, and ignored most solicitations for play and social grooming. In each group, most of the active friendly interactions were between the adult male and one particular female. Interactions between the male and the other female were hostile, while those between the two females were friendly but passive. These results are in keeping with the generally-held view that nocturnal prosimians are relatively unsociable but they are in striking contrast to those of an earlier study (EHRLICH & MUSICANT, 1977) in which a related species, the slow loris, was observed in the identical laboratory environment and was found to be highly sociable. It would seem, then, that a wide range of behavioral variability exists among nocturnal prosimians - even when species are compared that share a common behavioral repertoire.

Determinants of Response of Wolf Pups To Auditory Signals

Abstract: Two naive wolf pups (Canis lupus) were presented a variety of sound stimuli, including standardized recordings of natural and synthetic adult howls. The greatest and most consistent vocal response was elicited by the "real" howls. The nature of the response depended in part upon the i) type of stimulus, 2) number of stimulus presentations, 3) associated manipulations of context, and 4) individual differences in vocal responsiveness. Neither specific ongoing behaviors nor general activity levels of the pups appears to have mediated their vocal behavior. Differential responses demonstrated their ability to distinguish between recorded howls of adult wolves. Manipulation of the context, through presentation of either a human observer, live dog, or live mice increased the pups' vocalizations to the recordings. The results are discussed in terms of both extrinsic and intrinsic determinants of an animal's response to communication signals.