Showing papers in "Behaviour in 1974"

Observational study of behavior: sampling methods.

Abstract: Seven major types of sampling for observational studies of social behavior have been found in the literature. These methods differ considerably in their suitability for providing unbiased data of various kinds. Below is a summary of the major recommended uses of each technique: In this paper, I have tried to point out the major strengths and weaknesses of each sampling method. Some methods are intrinsically biased with respect to many variables, others to fewer. In choosing a sampling method the main question is whether the procedure results in a biased sample of the variables under study. A method can produce a biased sample directly, as a result of intrinsic bias with respect to a study variable, or secondarily due to some degree of dependence (correlation) between the study variable and a directly-biased variable. In order to choose a sampling technique, the observer needs to consider carefully the characteristics of behavior and social interactions that are relevant to the study population and the research questions at hand. In most studies one will not have adequate empirical knowledge of the dependencies between relevant variables. Under the circumstances, the observer should avoid intrinsic biases to whatever extent possible, in particular those that direcly affect the variables under study. Finally, it will often be possible to use more than one sampling method in a study. Such samples can be taken successively or, under favorable conditions, even concurrently. For example, we have found it possible to take Instantaneous Samples of the identities and distances of nearest neighbors of a focal individual at five or ten minute intervals during Focal-Animal (behavior) Samples on that individual. Often during Focal-Animal Sampling one can also record All Occurrences of Some Behaviors, for the whole social group, for categories of conspicuous behavior, such as predation, intergroup contact, drinking, and so on. The extent to which concurrent multiple sampling is feasible will depend very much on the behavior categories and rate of occurrence, the observational conditions, etc. Where feasible, such multiple sampling can greatly aid in the efficient use of research time.

The Social Organisation of Antelope in Relation To Their Ecology

Abstract: The types of social organisation displayed by the African antelope species have been assigned in this paper to five classes, distinguished largely by the strategies used by the reproductively active males in securing mating rights, and the effects of those strategies on other social castes. The paper attempts to show that these strategies are appropriate to each class because of the effects of other, ecological, aspects of their ways of life. The paper describes different feeding styles among antelope, in terms of selection of food items and coverage of home ranges. It argues that these feeding styles bear a relationship to maximum group size of feeding animals through the influence of dispersion of food items upon group cohesion. The feeding styles also bear a relationship to body size and to habitat choice, both of which influence the antelope species' antipredator behaviour. Thus feeding style is related to anti-predator behaviour which, in many species, influences minimum group size. Group size and the pattern of movement over the annual home range affect the likelihood of females being found in a given place at a given time, and it is this likelihood which, to a large extent, determines the kind of strategy a male must employ to achieve mating rights. The effects of the different strategies employed by males can be seen in such aspects of each species' biology as sexual dimorphism, adult sex ratio, and differential distribution of the sexes.

Courtship Persistence and Female-Guarding as Male Time Investment Strategies

Abstract: Time investment strategy is defined as the optimum allocation of times spent on given activities so as to achieve maximum reproductive success. Selective pressures on males to increase time invested in encountering females would be least in sessile and communally spawning species, and maximum in mobile species which spawn at low density and those which copulate. The present paper concerns male time investment in courtship persistence and female-guarding. Staying with a given female reduces the rate at which new females are encountered. Females are often unreceptive for some time after mating. Males often court unreceptive conspecific females; they can achieve a gain if the female rejection reactions can be overcome (rape) and the ejaculate can compete in the fertilization of the ova. Courtship of unreceptive females of closely related sympatric species is also considered adaptive. Though female unreceptivity will be favoured if hybrids are disadvantageous, males may gain by attempting rape if the fitness of hybrid offspring is high enough and the time investment favourable. A model is constructed to explain how optimum persistence durations are determined. This depends on 1) how the cumulative probability of insemination changes through time invested, 2) the encounter frequency, 3) the ejaculate cost (measured as feeding time investment/ejaculate), and 4) is modified by the pattern of gain from other types of female. Females can adapt to male persistence either by acceptance, by increasing rejection effectiveness, or by dispersing into another area where it is disadvantageous for males to search. This last solution may have been especially important in sympatric speciation. Male courtship duration with potentially receptive conspecific females may also be optimized. Variation in male persistence time may be due to assessment of particular situations. Female guarding has commonly evolved as a male time investment strategy. Precopulatory guarding appears to function to stake a claim to a female (or females) until she becomes receptive. This poses two problems : at what point in the female's reproductive life does it become advantageous for the male to guard, and how is guarding time optimized? Optimum guarding duration can be determined with the same model as for courtship persistence. If males adopt a given cue for closeness to receptivity for the onset of guarding, females showing the cue become scarce and selection may favour drive for earlier and earlier cues. This could be stabilized by the opposing selective pressures of 1) chances of finding a female closer to mating high enough, 2) female distribution suitably non-random with respect to mating, and 3) guarding investment more costly than searching investment in terms of male future reproductive success. Postcopulatory guarding appears to function to prevent loss in gain to a male due to sperm competition from other males. Such behaviour could evolve in conditions of high female receptivity and high encounter rate during an adequate overlap period (time per female during which ejaculates from different males can compete for fertilization of the ova), since males which guard after mating may waste less time and sperm than non-guarders. Its advantage is increased by a male-biassed sex ratio during the overlap period. The behaviour depends on the fact that second matings can compete in the fertilization of the ova, and postcopulatory guarding has its higlest advantage when the last male to mate fertilizes most eggs. Optimum guarding duration can be determined with basically the same model as before, and depends mainly on how sperm utilization is distributed within the overlap period.

Colonial Nesting and Social Feeding as Strategies for Exploiting Food Resources in the Great Blue Heron (Ardea Herodias)

Abstract: In this paper I present data collected to test certain predictions arising from the hypothesis that colonial nesting and social feeding in birds are adaptations that enhance the efficiency of exploitation of unpredictable food supplies. The hypothesis suggests that individuals benefit from nesting in colonies because they have the opportunity to learn about good feeding areas by following other birds from the nesting colony to the feeding grounds. If a bird is unsuccessful on one foraging trip, it will observe and follow more successful birds on subsequent trips; in this way the colony acts as an 'information centre'. I collected two types of data to test this idea as applied to the Great Blue Heron (Ardea herodias). (i) I recorded flights of parent birds. (ii) I measured the rate of food intake of birds hunting for food in flocks of different sizes. The analysis of foraging flights from the colony showed the following: (a) The birds used different feeding grounds on different days; this suggests that the food supply is ephemeral. (b) The birds tended to leave the colony in groups, which would be expected if they were following each other. (c) Birds from neighbouring nests tended to use the same feeding grounds and tended to leave the colony in groups (within the overall grouping of the colony as a whole). This would be expected if birds mainly copy their near neighbours. All these results support the idea of an information centre. I did not collect any data on whether successful birds were being followed by unsuccessful ones, but the data do seem to show that birds follow one another. On the feeding grounds, I showed by use of models that herons are attracted to feed in areas where there are other birds, and that they are more attracted by a group than by a single bird. If flock feeding helps in locating good feeding places, we can expect that flock birds would do better in terms of food intake than solitary individuals. A step-wise multiple regression showed that rate of food intake of a bird (grams of fish caught per minute) is an asymptotic function of flock size. A bird in a flock of 20 gets about 5 times as much food per minute as a solitary bird. Further, the percent success (i.e. strikes resulting in a capture) is higher in flocks, and the coefficient of variation of feeding rate is lower. Thus flock birds get more food for relatively less effort and stand a smaller chance of doing very badly in terms of food intake. I discuss various possible explanations of the advantage of the flock birds, and conclude that it is not a result of searching harder, less 'nervousness' of predators or stirring up the fish to make them easy to catch. It is a consequence of the fact that flocks only build up where feeding conditions are good. I present a simple graphical model to show how this happens. In conclusion, my results support the idea that colonial nesting and social feeding are adaptations concerned with finding food, but there are also other factors involved in the evolution of sociality in ardeids and other birds.

The Food Searching Behaviour of Two European Thrushes. Ii: the Adaptiveness of the Search Patterns

Abstract: 1) This study describes the searching behaviour of two thrushes foraging for both naturally occurring and artificial foods. I have paid particular attention to temporal and spatial changes in searching behaviour and have attempted to answer the question of whether the changes in searching behaviour were adaptive ones. 2) When thrushes captured an earthworm and continued searching, they showed a net change in patterning of the twelve turns following capture so that they probably searched the area surrounding the capture point more thoroughly than an area covering the same number of moves units before capture (Figs 4, 5; Table 1). This confirms N. TINBERGEN'S (1967) hypothesis that path changes sometimes follow prey capture in bird predators. Since earthworms on the study meadow were aggregated in distribution, the net change in path may have been of adaptive value to the thrushes, by concentrating their search where further prey items were most likely to occur. It was not, however, possible to relate the increased searching effort quantitatively to the size of the earthworm aggregates. (3) The thrushes were then presented with populations of cryptically-coloured artificial prey in random, regular and aggregated distributions at each of two densities (Fig. 7). The movements of the thrushes (mainly blackbirds) feeding on these prey were recorded as described by SMITH (1974). (4) The overall distribution of the search paths of the thrushes showed a correspondence with the distributions of the artificial food populations (Fig. 9). The thrushes made larger turns and showed less tendency to alternate left and right turns at the higher density (Tables 8, 11), thus helping them to maintain their search paths within the smaller confines of the high density populations. (5) The capture rates of the thrushes at the two prey densities were roughly proportional to the differences in prey density (Table 4). Although there were suggestions of differing capture rates, unforeseen errors in experimental procedure did not allow firm conclusions on the effects of thrush predation on the different prey distributions within each density. (6) The presentation of the cryptic artificial prey led to an increase in the average length of moves made by blackbirds (Fig. 10; Table 5). Further increases in move length followed the cutting of the grass on the study meadow (Fig. 13) and the introduction of more conspicuous artificial prey (Figs 11, 12). It is suggested that the increases in move lengths were an adaptive reaction by the blackbirds to increases in prey detectability. (7) Captures of single artificial prey were preceded by larger than average turns and were followed by larger than average turns in the opposite direction (Table 9). (8) The presentation of the artificial food led to an overall increase in the speed of movement of the blackbirds (Table 10). (9) After the capture of prey in the low density random and aggregated populations thrushes showed a net tendency to concentrate their searching in the area surrounding the site of prey capture (Fig. 16; Table 12), similar to that shown after the capture of earthworms. This was not shown after the capture of regularly distributed prey (Figs 16, 17 ; Table 12), nor was it clearly shown after the capture of prey in the high density random and aggregated distributions (Fig. 17; Table 12). (10) The overall speed of movement was greater over the ten moves preceding capture than over the ten moves following capture in the low density regular distribution (Table 13). (11) The changes in searching behaviour following capture are discussed with reference to N. TINBERGEN'S (1967) hypothesis that predators select for 'spacing out' in prey. (12) A method is presented which allowed the measurement of the wild blackbirds' abilities to detect the artificial prey supplied (Figs 18-20). The 'risk' to the artificial prey was high when the blackbirds were within 20 cm of the prey, but fell to near zero at a distance of 120 cm. (Fig. 21). The square root of the risk was linearly related to the distance between predator and prey (Fig. 22). The measures of the detection ability of the blackbirds are discussed in relation to their movement patterns. (13) The results are discussed in light of the general problem of whether predatory animals show adaptive flexibility in response to spatial and temporal variations in food supply. I have argued that at least some aspects of the thrushes' behaviour provide evidence for such flexibility. I have emphasised that the basic 'unpredictability' of the environment, which generates the need for behavioural plasticity, also makes it unrealistic to expect to find predators making optimally adapted responses to all variations in the environment.

Electric Communication: Functions in the Social Behavior of Eigenmannia Virescens

Abstract: Eigenmannia virescens was observed in aquaria in Guyana, South America, during the non-breeding and breeding seasons. Agonistic behavior was described and correlated with electrical activity. Variations in the electric discharges play important roles in agonistic behavior as displays given during attack and retreat. Although descriptions of sexual behavior are not complete, certain electrical signals also appear to be used in courtship. The role of electrical signals in agonistic behavior of Eigemnannia were studied by (1) an analysis of the behavior of fish in dominant and subordinate roles, (2) an analysis of the simultaneous occurrence of electrical displays and motor actions, (3) an analysis of preceding actions of one fish and following actions of the other fish, and (4) analysis of responses to artificial electrical stimuli. These studies indicate that at least three classes of electric signals are important in communication among Eigenmannia: the normal discharge, Interruptions, and Rises. The normal discharge. The normal discharge of Eigenmannia virescens is species-distinctive in the area where this study was conducted. Playback of recorded signals and presentation of sinusoidal electrical stimuli, indicates that the normal discharge particularly the fundamental frequency of the normal discharge (240 to 600 Hz)- is used in species recognition. Males and females overlap extensively in their discharge frequency, and males do not appear to distinguish the electric discharges of males from those of females. Interruptions. Interruptions are brief cessations of the electric discharge. They are most often 20 to 40 msec in duration during agonistic interactions whereas they are often 60 to 80 msec when given by males during interactions with females during the breeding season. Interruptions are usually given in bouts where a bout is any group of Interruptions separated by less than 1.5 seconds. Interruptions are given almost exclusively by dominant fish. They are given at the same time as Attacks, Threats, and No Action, but rarely during Retreat. Bouts with many Interruptions are more likely to be associated with Attacks, and less likely with No Action, than are bouts containing only a few Interruptions. Interruptions correlate with motivation to Attack, and the number of Interruptions in a bout correlates with the probability of attack. Interruptions in one fish are followed by Retreat and No Action in the other fish, thus they appear to be an effective threat display. Interruptions with long durations are given at high repetition rates by male Eigenmannia in the presence of females during the breeding season, thus they may play a role in courtship. Rises. A Rise is an increase in discharge frequency followed by a decrease to the resting frequency. Rises lasting less than two seconds (Short Rises) are often given by dominant fish in agonistic interactions, most often at the same time as Attacks or Threats. They are given rarely. Long Rises (longer than two seconds) are given predominantly by subordinate fish in agonistic interactions. They are given simultaneous with Retreat and No Action and are thus an indicator of submissive behavior. Long Rises in one fish are followed by Attacks, Threats, Approaches, and by No Action in the other. During the breeding season, females, in the presence of males, often give long series of frequency modulations of unknown significance.

The Food Searching Behaviour of Two European Thrushes

Abstract: 1. The movement path of a predator will clearly be an important determinant of its ability to encounter and subsequently attack suitable prey items. Previous work on this aspect of searching behaviour has been mainly carried out on invertebrates, while this study describes the movement paths of two bird predators, the european blackbird and the song thrush (collectively referred to as 'thrushes') on a grass meadow in central Oxford. 2. The paths of foraging thrushes are divided up into natural units consisting of a series of alternating moves and pauses. A method of mapping these moves is presented (Figs 2, 3). 3. The large scale movements of the thrushes on the meadow was not uniform and this was probably related to non-uniformity in the environment, possibly including factors influencing feeding success (Figs 4, 6). 4. The durations of the moves and pauses were measured from cine film and video tape records. Only between one sixth and one tenth of the total foraging time was spent in actual movement, the remainder probably being spent largely in scanning for, or attacking, potential prey objects (Figs 7, 8). 5. Measures of the individual move lengths and angles. turned between successive moves were taken from the maps (Figs 3, 9), and the average speeds of movement were calculated for each track. Song thrushes and female blackbirds made longer moves than male blackbirds, and female blackbirds moved across the meadow at a higher overall speed than male blackbirds or song thrushes (Tables 1-4). 6. Methods are presented for describing the 'rules of movement' of the thrushes across the study meadow. When feeding mainly on earthworms, thrushes tended to make sequences of three, or possibly more, moves that were similar in length, and to make pairs, triplets, and possibly bigger groupings of alternating left and right turns. The size of each move was independent of the sign of the preceding turn and vice versa. The tendency of successive turns to alternate in sign, combined with the relatively restricted size of turns between moves, produced an ongoing search path, thus avoiding the pitfall of searching the same ground twice in a short time.

Triadic differentiation: an inhibitory process protecting pair bonds in baboons.

Abstract: Field observation and pilot field experiments suggested the hypothesis that a social inhibition prevents male hamadryas baboons from encroaching on each other's females. The hypothesis was tested in a set of enclosure experiments which led to the following results : 1. When two males were simultaneously confronted with an unfamiliar female, one would become her "owner", either by defeating his rival or by the latter's withdrawal. 2. No fights occurred, however, when one male was allowed to watch a troop mate interact with a new female before he was admitted to them. He then respected the pair bond even if he was dominant over the owner. This agreed with the inhibition hypothesis. The alternative dominance hypothesis was rejected at the 0.01 level. 3. When males from different troops were used, some rivals attacked the owners and took their females. Most attacks were directed by powerful rivals against the particularly inferior males of one troop, suggesting that dominance factors can, in extreme cases, override the rival's inhibition. 4. The inhibition appeared to be restricted to the context of owning females in that it did not significantly affect the male's performance in food dominance tests. 5. A few casual interactions between the pair sufficed to inhibit the rival. The owner's overt demonstrations of possession had no additional effect in these experiments. 6. The stabilizing functions of the inhibition in the hamadryas society are discussed. 7. The inhibited rivals performed a number of redirected and conflict activities. An analysis shows that the inhibition suppresses friendly as well as aggressive approaches in the rival, thus keeping him away from the pair. 8. The owner's interactions with the rival were also inhibited, but much less than the rival's interactions with the pair. In contrast, interactions between the pair were increased and intensified by the rival's presence. 9. In one exceptional test, the female appeared in the role of the excluded rival. The formation of triads thus seems to reduce two of the component dyadic relationships while furthering the third. The possible mechanisms of such "triadic differentiation" are mentioned and its probable function in the formation of groups and subgroups is outlined.

The Effects of Other Fish On the Reproductive Behavior of the Male Cyprinodon Variegatus (Pisces: Cyprinodontidae)

Abstract: This study was conducted to investigate the effects of both inter- and intraspecific intruders on the reproductive behavior of Cyprinodon variegatus. Field observations suggested that the highly aggressive male Cyprinodon prefer to chase their own species, then Fundulus heteroclitus, followed by Lucania parva and Gambusia affinis last. In a series of laboratory experiments, in which dominant males were given various combinations of uni-specific and hetero-specific groups to chase, strong evidence was produced for the chase preferences predicted from field observations. The effects of intruders on the spawning behavior of the male were also recorded. In the field the female entered the male's territory, spawned an average of four times and then left. A female spent approximately 20 seconds in the male's territory. While other fish did interrupt spawning, only neighboring territorial males actually interfered physically. This interference occurred if the spawning pair ventured too close to the border (approximately seven cm). In the laboratory conspecific intruders significantly reduced both the number of spawns and the total duration of contacting (i.e., a side-by-side position of the pair, occurring just before spawning). These intruders also increased the probability of long spawning intervals following other long intervals. At the same time, intruders caused the pair to produce relatively more short intervals. Thus, when other Cyprinodon males were present, the pair had a tendency to perform a clustering of spawns which was separated by several long intervals. This resembled the field situation in which a female entered, spawned several times and quickly left. This study suggests that the effects of other interacting fish should be considered when analyzing reproductive behavior. The observation of laboratory fish in isolated pairs may produce misleading results as to the evolution and/or maintenance of behavior.

L'Impregnation Dans L'Ontogenese Des Comportements De Soins Aux Cocons Chez La Jeune Fourmi Rousse (Formica Polyctena Forst.)

Abstract: Young worker ants of the species Formica polyctena separated from the mother-colony on the day of hatching and reared in groups of 250 to 300 individuals will accept and care for the cocoons of a different species, even of a different genus (Formica sanguinea, F. pratensis, Camponotus vagus, and Lasius niger). If such a group of young workers has been in contact, during the first fifteen days of life, with cocoons of one or another of these species (and in the absence of cocoons of their own species) only cocoons of this same species are subsequently accepted and tended. Cocoons of their own species are not recognised as such but treated as food. Worker F. polyctena which have matured in the presence of cocoons of their own species devour those belonging to strange species. When cocoons are totally absent from their early environment the workers turn out to be incapable of tending the cocoon of any species, including their own kind. It thus appears that the first fifteen days of life constitutes a critical or sensitive period during which the stimulation received by young worker from the cocoons has a powerful influence on the behaviour which it will later manifest as an adult. This stimulation appears, indeed, to be an indispensible element in ontogenesis of the behaviour of caring for the cocoons. In the majority of the experimental colonies the "familiar" cocoons are still recognised after a six months period of hibernation, in the absence of all cocoons. It seems that the characteristics of this phenomenon, and those of a sensitive period and memorization in particular, are essentially those of Imprinting as described in various Vertebrates. An unusual aspect of the phenomenon however, which is related to the social structure existing among ants, is provided by the fact that the efficiency of the imprinting is increased by the presence of a queen amidst the cocoons during the sensitive period.

Temporal Leks as a Mating System in a Temperate Zone Dragonfly (Odonata: Anisoptera) I : Plathemis Lydia (Drury)

Abstract: The behavioral ecology of Plathemis lydia (Drury) (Odonata: Anisoptera) was studied at several ponds in northern New York State. Males and females utilized restricted areas of the ponds. Female occurrence was highest during a short time period each day, while males occurred throughout most of the day. Thus, males and females were considered to be highly predictable in time and space. Males returned daily to a traditional area which was utilized primarily for mating. Ali males on one area interacted aggressively with each other to establish a dominance hierarchy. Each individual on the area appeared to recognize and maintain the integrity of the territorial boundaries. The organizational system allowed conspecific trespassers which showed submissive behavior within the defended area. The dominant male had the advantage, relative to the subordinate conspecific at the site, in clasping and copulating with females which flew into the area. The dominance hierarchy on the traditional mating area appeared to increase the reproductive efficiency of the dominant male. Time budgets and analyses of mating behavior of males under various densities are presented and analyzed with reference to a time-energy-maturational-experiential hypothesis for the evolution of the behavior. Comparisons are made between dragonflies and birds and mammals which exhibit similar types of behavior.

Examination of the Agonistic Behaviour of the Crayfish Orconectes Virilis By Character Analysis

Abstract: The agonistic behavior of the crayfish Orconectes virilis was observed in the laboratory, with attention to the effects of size, past experience, and displays. Character analysis was utilized to quantify the relative importance of these three factors. I) In short fights, larger animals and animals which had won previous fights had a decided advantage. 2) In long fights, size and past experience seemed to have little influence on who would win. 3) Initiating an interaction gave an animal and advantage in short fights or when both were the same size. 4) Model presentations indicated that postures assumed during fights were effective visual stimuli and that the white areas on appendages are important components of displays. 5) The greatest reduction in uncertainty concerning which behavior pattern would occur at any time in a fight came from knowing the just previous act of the other crayfish. 6) The amount of information transmitted from one crayfish to another by displays increased during fights to a peak of 160 bits (53% uncertainty reduction) in the middle of fights. 7) Partitioning the data into long or short fights and into initiator-won or defender-won fights increased the apparent importance of inter-animal communication.

Some studies on the use of "standard opponents" in intermale aggression testing in TT albino mice.

Abstract: An investigation involving the use of young, naive, grouped male mice as "standard opponents" in intermale aggression tests was carried out. Castrated "standard opponents" were less effective in eliciting fighting behavior from mature, isolated male test animals than intact opponents on the second day of testing. When changes in a number of aggression test parameters were considered with respect to fighting experience, it was found that the most obvious change in behavior was evident between the first and second tests. It seems likely, in the light of studies which compare the "round robin" test and the "standard opponent" test that the latter test is a means of precluding much of the conditioning evident in the "round robin" as well as being a much faster procedure.

Agonistic Behavior of the Blue Crab, Callinect Us Sapid Us Rathbun

Abstract: 1 Behavior patterns of blue crabs (Callinectes safridus) were observed in both field and laboratory Most agonistic acts employ the chelipeds, which can serve as organs of expression as well as weapons They are spread in threat, used to ward off or grasp an opponent, or folded in "crouching", which appears to be a submissive gesture These acts serve to halt the approach of other individuals or to cause them to withdraw Vigorous combat was seen only when they failed to deter crabs that were attracted to food or a sexually receptive female held by another individual 2 Differences were found in the distances between crabs at which various agonistic acts occurred The responses by crabs to individuals that were approaching differed with their own orientation and with that of the approaching animal The frequency distribution of the various acts also differed with the size and sex of the crabs, and with the presence of food or a receptive female 3 Presentation of a model of an adult male crab to captive animals showed that agonistic responses differed with the speed of approach, orientation, cheliped posture and distance of the model, and with the sex and size of the crabs Animals responded to the model more often when it approached rapidly, frontally or with extended chelipeds than when it approached slowly, laterally or with folded chelipeds Females responded to the model more often than did males, and smaller individuals similarly responded more often than did larger ones In cases where animals responded more frequently, they typically extended their chelipeds, crouched or withdrew from the model

The Vocalizations of Some Hybrid Treefrogs: Acoustic and Behavioral Analyses

Abstract: The vocalizations of natural hybrids between various species of treefrogs (Hylidae) are compared with the vocalizations of the parental species : 1. In most respects, the calls of two males of H. avivoca X H. chrysoscelis and of six males of H. cinerea X H. gratiosa are intermediate. 2. The vocalizations of three males of H. femoralis X H. clarysoscelis tend to be similar to those of males of H. chrysoscelis. 3. The calls of each of the hybrids are composed, however, of some features which are intermediate, some which are similar to one of the parental species, and others which are unique to hybrid calls. Differentiation of the calls of males of H. avivoca, H. chrysoscelis, H. femoralis, and hybrids in this group is mainly in the temporal domain. Females of H. chrysoscelis and H. femoralis responded only to the calls of males of their own species in discrimination experiments where hybrid calls were alternative stimuli. The calls of males of H. cinerea, H. gratiosa and hybrids between these two differ primarily in their spectral composition : the two spectral peaks have different locations in each kind of call. In discrimination experiments, females of H. gratiosa responded only to conspecific calls when the calls of hybrids were equally accessible. Females of H. cinerea showed partial discrimination against the calls of hybrids. Females of both kinds often responded to the calls of hybrids when conspecific signals were unavailable. In general, the closer the spectrum of a natural call resembled that of conspecific calls, the more attractive was the acoustic signal.

The Development of Sociosexual Behaviours in Japanese Macaques Macaca Fuscata

Abstract: Sociosexual behaviours were observed over a two-year period in a natural troop of about 100 Japanese macaques (Macaca fuscata) confined in a two-acre corral. The development and mature expression of integrated patterns of mounting, presenting, thrusting, and related behaviours were examined. The frequency and type of mounting varied dramatically with the season of the year. Male-female, female-male, and female-female mounting were most frequent during the 6-month breeding season when males 4½ years and older can ejaculate and females 3½ years and older can conceive. Ejaculation generally occurred only after a series of mounts. Mountings in series by and on either sex were largely confined to the breeding season. Female presenting and male thrusting and certain other behaviours accompanied mounting more often at that time of year also. In the nonbreeding season, heterosexual interactions decreased but male-male mounting increased though it never reached breeding season levels for male-female mounting. Nonbreeding season mount events between both sexes and all ages typically involved only a single mount, but most were accompanied by thrusts. The type of interaction between pair members also differed; most mounting occurred during play. In males, mounting and thrusting were integrated gradually according to the season and sex of partner. By six months of age, males oriented to a partner's buttocks and used a double-foot-clasp posture on most mounts. At 1½ males mounted females more frequently than males and by 2½ showed the seasonal cycles in mount frequency and partner choice. They reached peaks in mount event frequency at 4½, but the most efficient and stable patterns were seen in males over 7 years of age. Although females showed thrusting movements early in life, they seldom mounted except on males during breeding season and occasionally during play or agonistic situations. They were most active as mount partners and actors after 3½ years of age. Their subsequent activity varied with the individual and her reproductive state. Several conclusions can be drawn from this and other studies on the development of sociosexual behaviours in primates. 1. Rearing conditions are crucial to the development and integration of postures, thrusting, intromission, and ejaculation. The most important element for normal development is the mother; however, the presence of other adult and encouraging females helps a young male to integrate the various elements. Peer males and females also facilitate or allow the expression of a variety of patterns and probably provide a source of enduring attachments and mature partner preferences. The role of the adult males in development is both positive and negative depending on the male, the group, and the species. 2. The most important aspect of normal sociosexual development is the differentiation and integration of elements such as mounting, presenting, thrusting, intromission into two patterns : the primarily copulatory and the primarily contacting. Intromission seems to be a key element in the differentiation process. Factors that facilitate intromission speed the process; factors that inhibit intromission delay the development of the young primate male's ability to distinguish correctly between postures, partners, and situations. The copulatory patterns of females seem less affected by unsatisfactory rearing conditions, but the sociosexual patterns of contact may be disturbed. 3. Mature sociosexual patterns develop from close physical contact with the mother or mother substitutes. Erection and thrusting appear independently but soon become linked to ventral clinging, embracing, riding, and mounting. Mount and present postures develop quickly and vary according to species and pairings and contexts. The most stereotyped posturing and patterns appear in the copulatory context: the sociosexual patterns retain their variability in form and variety of expression in different contexts, mainly affiliative and more rarely, agonistic,

Arousal and the Causation of Behaviour

Abstract: A. A number of very different meanings have been given to the term "arousal". These have here been distinguished as follows: (1a) Responsiveness. The likelihood at a particular moment that any one of a number of different stimuli will evoke the response appropriate to it if presented. (ib) Behavioural intensity. A variable which affects the vigour and completeness of whichever response is elicited. (2) Activation. A variable, systematic changes in which determine the kind of response which is possible (e.g. grooming or copulation). (3) Arousal as drive. A variable which explains the association together in time of a group of responses, which may be held to include alert responses, cardiac acceleration, increase in postural tonus and a variety of "emotional" responses. (4) Level of sensory input. A variable which regulates the level of sensory input. Mechanisms of selective attention are often included. (5) Property of a functional system in the CNS. The syndrome resulting from increased activity in the ascending activating system. Some or all of these meanings are commonly confused together, which greatly reduces their value in description and analysis. Further it is usually assumed, but with little little firm evidence, that changes in all these variables are continuous and similar in nature from deep sleep to states of extreme wakefulness. These latter states have rarely been clearly characterised. B. For a number of studies the use made of arousal as an explanatory concept is discussed. (1) Changes in responsiveness are important in behaviour, and deserve wider study and theoretical discussion. Data on behavioural intensity are scanty. (2a) Activation models can be used to explain changes in the likelihood of different acts through the course of normal behavioural cycles from one period of sleep to the next. However, except for grooming which tends to occur before and after drowsiness, most acts appear to be affected by a general progressive increase in responsiveness following awakening. The existence of a number of groups of acts, each associated with a particular range of activation (arousal) remains to be proved. (2b) Experimental manipulation of drowsiness in the chick by the administration of hexoses either into the crop or directly into the hypothalamus and other areas of the brain, has at least three relatively independent effects on behaviour. Drowsy periods interfere directly with other responses. At the same time approach to drowsiness is accompanied by a loss of inhibition in responses such as pecking. This is probably due to reduced forebrain activity since it can be reproduced by spreading depression due to KCl. Finally, familiar surroundings are treated as novel immediately after waking. The second and third effects cannot be handled by activation models. (2c) Attempts to vary activation by startling and painful stimuli have shown that some responses may be markedly and unexpectedly facilitated (e.g. copulation by electric shock). However, other startling stimuli may have no effect at all, and recovery from the stimulus does not show the sequential facilitation of a number of different acts which an activation model would predict. (3) Various cardiovascular, respiratory, thermoregulatory and other reflexes, which represent feedforward regulation of the physiological consequences of a predicted increase in exertion, have been held to be indices of heightened arousal. Their use as such is complicated by the fact that the sustained activation of such reflexes in the absence of exertion is inevitably disturbed by feedback regulation of the disturbances which result. Further, a novel stimulus can also produce preparations for immobility (e.g. cardiac deceleration), if the animal examines it carefully rather than at once responding. Attempts to explain changes in these two complexes of reflexes in terms of arousal changes have become so confusing that they are best abandoned. The pattern of alert responses shown at waking is commonly taken as the behavioural counterpart of cortical arousal. However, once waking has occurred it is not possible to identify further patterns of alert responses which can be used to characterise a series of states of progressively increasing arousal. Instead at least two phases of attention, scanning and focussed, can be distinguished over a wide range of states of responsiveness or autonomic arousal. (4) Estimates of the rate of intake or of passage of information are extremely difficult. They are complicated by the fact that studies of selective attention have shown that preliminary recognition of stimuli proceeds in channels other than that in primary use, so that any definition of arousal in terms of information passage must also consider the extent to which attention is confined to the primary channel. Evidence for the homeostatic regulation of arousal, so defined, is indirect and scanty. (5) At least two brain mechanisms are primarily responsible for different phenomena which have been ascribed to arousal. The ascending activating system (AAS) is involved in the appearance of alert responses in a previously drowsy animal, whilst the central mesencephalic grey (CMG) and its diencephalic connections appear to mediate both preparations for exertion and such "emotional" responses as piloerection. The relationship between the two systems and, in particular, the effects of sustained activation of the AAS in the absence of effects on the CMG require further study uncomplicated by prior assumptions about the nature of arousal. It is probable that other of the phenomena discussed here are also primarily mediated by relatively independent brain structures (e.g. focussed attention and the hippocampus).

Juvenile Play of the Common Seal Phoca Vit Ulina Vit Ulina With Comparative Notes On the Grey Seal Halichoerus Grypus

Abstract: Juveniles of the common seal, Phoca vitulina, have two kinds of aquatic play : (1) Dyadic play, in which muzzle-to-body and body contact between two animals is combined with exuberant somersaulting movements. The somersaulting behaviour is usually preceded by a contact phase with very little movement. A play bout may end with a period of sustained, almost static contact. (2) Group play, which resembles the normal social haul-out activities, but each activity is repeated several times in a playful manner. Although several animals may be leaping and splashing simultaneously, each animal temporarily orients his play towards one other, whom it may contact briefly. All play by juveniles of the grey seal, Halichoerus grypus, is preceded by each animal of the dyad giving a stereotyped invitation signal, which must be repeated continually by both animals throughout play : each animal in turn lays its head over its partner's back. For the initial phase of play which takes place on the beach, the two animals lie beside one another, each lunging gently at the other's head, in between head-over-back signals. Adolescents may occasionally rear up and lunge at each other in a manner similar to the fighting of adult males. After playing on the beach, the pair may enter the water, where their play is similar to the dyadic play of the common seal. The aquatic somersaulting over one another by two animals in continuous body contact seems to be a pattern not found in these two species in other functional contexts. Common seal group play serves to (i) integrate the individuals into a unified group, and (ii) acquaint individuals. Although grey seals apparently do not have group play, behaviour which is probably functionally analogous was observed, in which the seals became acquainted over a 3-week period in early autumn before any play occurred.

Individual Chick Recognition and Family Integrity in the Ring-Billed Gull

Abstract: In field experiments designed to determine the nature and chronological development of chick recognition by natural-breeding Ring-billed Gulls, adults tending broods for a variable number of days were given recognition tests by replacing their own young with chicks from other nests. Introduced chicks of the same age as the resident brood were nearly always accepted during the first 5 days posthatching and usually rejected after the 7th day whether or not a resident chick remained on the territory. Adults with 7-day-old chicks presented with substitute 2-day-old broods either pecked or abandoned the younger chicks in almost all cases. Adults repeatedly presented with normally advancing-age substitute chicks each morning for the first eight days posthatching showed no signs of rejecting substitute chicks at any point. The pattern of parental activity shown by these birds resembled that of controls allowed to associate continuously with their own chicks. To examine the perceptual basis of recognition, a series of resident chicks 12-20 days old were surgically devocalized, and another series were marked with black ink to alter their individualistic plumage and facial patterns. No changes were observed in the behavior of parents toward muted or near-muted chicks, but over half of the parents attacked the visibly altered chicks. These attacks diminished within a few hours as the chicks persisted in showing positive approach responses to the attacking parent. In similar tests with 3- to 4-day-old chicks marked in the same way there were no rejections, suggesting that the markings did not, in themselves, constitute releasers for aggressive attack. The major findings of the study are interpreted as follows: a. Parent Ring-billed Gulls are able to recognize their own chicks after about 7 to 9 days posthatching, the stage at which increasing mobility terminates the family isolating mechanism provided by territorial boundaries. b. In identifying their own chicks, parent gulls can use individual variations in physical appearance. They may also respond positively to the relaxed comportment characteristic of chicks in familiar physical and social surroundings. c. In the social congestion that prevails in a gull breeding colony, individual recognition between parent and offspring provides the basis for a system of exclusive family units. This system, along with territorialism during the egg and early chick stages, permits a breeding bird to channel its reproductive energy to its own offspring exclusively, thereby promoting its own genes in contention with competing-gene carriers in the colony.

An experimental study of aggression in captive European rabbits, Oryctolagus cuniculus (L.).

Abstract: Aggression in wild and domestic New Zealand White European rabbits, Oryctolagus cuniculus, has been studied in the laboratory. The experimental procedure was to introduce a strange animal into the pen of another "home" rabbit. All possible combinations of sex and type of breed were made in the 580 tests each lasting 150 seconds. Attention was paid to the occurrence of chasing, biting, ripping and mounting. The outcome of the confrontation was classified in terms of win, lose or draw. The data collected has been subjected to statistical analysis. All rabbits, irrespective of type or sex, were found to be able to fight and to be prepared to defend their own home. The incidence of victory of home animals over introduced ones was highly statistically significant (P<0.001) for all combinations of contesting animals with the exception of those in which New Zealand White does were confronted with introduced New Zealand White males. The reversal of home and introduced positions of two individuals reversed the outcome of the contest. Aggression was found to be equally prevalent in both sexes and inter-sexual fighting occurred just as frequently as fighting between members of the same sex. New Zealand White rabbits engaged in mounting more frequently than the wild animals but on the whole domestication did not eliminate their ability to fight. Domestic females paired together and domestic males paired with introduced wild animals of both sexes fought less frequently and less viciously amongst themselves than the other pairings. Rabbits introduced into foreign pens stamped more frequently than home animals. It seems that depending on circumstances stamping may be a part of different behaviour patterns and not necessarily a component of agonistic behaviour. The behaviour of "home" rabbits towards anaesthetised ones placed in their pens was studied and the results suggested that the lack of movement and resistance lessened the severity of the attacks by the home animals. The home individuals frequently chinned, licked and scratched the introduced anaesthetised rabbits although these forms of activity were absent during the confrontations with untreated animals. In the Appendix by M. L. DUDZINSKI & C. B. H. EDWARDS the data is analysed by the principal components method. This method of analysing multivariate data allows the geometrical demonstration of congregations - "clustering" - of separate behavioural components which is useful in revealing the relation between different categories of behaviour as well as the behavioural characteristics of separate groups of animals.

A Comparative Ethological Study of Strombid Gastropods

Abstract: The behavior of ten species of strombid gastropods (Strombus and Lambis spp.) was studied in the Marshall, Hawaiian and Line Islands. Measurements were made in both the laboratory and the field of the MAP's comprising feeding, locomotion, righting of overturned shells, and escape from predators, which reflect significant ecological and morphological determinents of behavior in the Strombacea. All species feed by grazing with the proboscis under the protection of the shell. All Strombids use the MAP Leap during locomotion. The rate of locomotion varies as a hyperbolic function of length; increasing with greater size in the genus Strombus and decreasing in the genus Lambis. Larger animals travel a greater distance with each leap but make fewer leaps/minute. Species of Strombus right their overturned shells by a Kick at the substratum with the operculum, but species of Lambis use the MAP Pull and turn the animal over with the operculum wedged under the shell. Only one attempt is needed in the species of Lambis, but more are used by the faster moving species of Strombus. Intention movements are performed during righting. Species of both genera escape from molluscivorous cones using the MAP's Tentacle Wave, Flip and Run. In the species of Strombus, Flip causes a backward movement of the shell off the substratum, but in species of Lambis the shell restricts the movements and the animal merely turns to one side. Escape locomotion is much faster than normal locomotion, due to the greater distances travelled with each flip by the smaller species of Strombus and the greater number of leaps/minute made by all species. The flip escape response appears particularly adapted for escape from dart-shooting predators. A review of the literature on strombid behavior shows that the behavior of all species within the Strombacea is remarkably similar even though there is great disparity in shell shapes. Because of similarities in soft body parts and behavior, the Xenophoridae should be retained within the Strombacea. It is suggested that the species within the Strombacea evolved in parallel from a common aporrhaid-like stock and the behavior has diverged less than shell form and is therefore a more conservative character in the group's phylogeny than is shell shape. The behavior of a snail can be greatly modified by its shell. Differences in behavior between Strombus and Lambis are attributed to restrictions imposed by the shell and not differences in body movements. Behavior must be adapted to the shell shape and both, of course, reflect the animal's ecological setting.

The Comfort Behaviour of Adélie and Other Penguins

Abstract: [Comfort movements include the behaviours of shaking, stretching, cleaning, preening, and washing. These were described and analyzed for Adelie Penguins. The function for some movements such as oil-preening was difficult to determine and could only be hypothesized. Cleaning, preening, washing, head-shaking, and sneezing function in the care of body surfaces and are responses to the presence of irritants or foreign material on surfaces. Stretching and other shaking movements may function to help prepare muscles and peripheral circulation for activity. Ruffle-shakes may function to dissipate heat and arrange plumage. Some movements of oil-preening and some areas of the body preened are performed in a predictable sequence ordered according to functional relationships among the different movements. Some movements are normally performed only after certain others have been performed. Bathing in penguins is a socially facillitated behaviour. The pattern of Adelie bathing is determined largely as an anti-predator strategy. Adelie, African, and Humboldt Penguins perform the same repertoire of comfort movements. The one exception is that both spheniscids allopreen but Adelies do not. The motor patterns of all other movements except for two are the same for the three species. The two spheniscids perform the jaw-stretch and the both-wings-stretch differently than does the pygoscelid. The comfort movement repertoires of several other penguin species were compared to these. Their repertoires were all very similar. Head-shaking is performed in Adelies during disturbance as a response to an increase in secretion rate of the salt gland. The increase in salt fluid secretion is probably a result of a change in autonomic activity. Head-shaking and social displays which include a form of head-shaking have been reported for several seabird species during disturbance or social interaction. In Adelie Penguins and albatrosses the increased head-shaking during these circumstances is a response to increased salt gland secretion. It is hypothesized that some of the head-shaking and head-shaking displays of other seabirds are caused in the same way. Head-shakes and other vigorous shakes and stretch movements probably have signal function during social interaction., Comfort movements include the behaviours of shaking, stretching, cleaning, preening, and washing. These were described and analyzed for Adelie Penguins. The function for some movements such as oil-preening was difficult to determine and could only be hypothesized. Cleaning, preening, washing, head-shaking, and sneezing function in the care of body surfaces and are responses to the presence of irritants or foreign material on surfaces. Stretching and other shaking movements may function to help prepare muscles and peripheral circulation for activity. Ruffle-shakes may function to dissipate heat and arrange plumage. Some movements of oil-preening and some areas of the body preened are performed in a predictable sequence ordered according to functional relationships among the different movements. Some movements are normally performed only after certain others have been performed. Bathing in penguins is a socially facillitated behaviour. The pattern of Adelie bathing is determined largely as an anti-predator strategy. Adelie, African, and Humboldt Penguins perform the same repertoire of comfort movements. The one exception is that both spheniscids allopreen but Adelies do not. The motor patterns of all other movements except for two are the same for the three species. The two spheniscids perform the jaw-stretch and the both-wings-stretch differently than does the pygoscelid. The comfort movement repertoires of several other penguin species were compared to these. Their repertoires were all very similar. Head-shaking is performed in Adelies during disturbance as a response to an increase in secretion rate of the salt gland. The increase in salt fluid secretion is probably a result of a change in autonomic activity. Head-shaking and social displays which include a form of head-shaking have been reported for several seabird species during disturbance or social interaction. In Adelie Penguins and albatrosses the increased head-shaking during these circumstances is a response to increased salt gland secretion. It is hypothesized that some of the head-shaking and head-shaking displays of other seabirds are caused in the same way. Head-shakes and other vigorous shakes and stretch movements probably have signal function during social interaction.]

Schallsignale Der Hausmaus (Mus Musculus)

Abstract: a) Es wurden 8 verschiedene Laute der weisen Labormaus (Mus musculus, Stamm NMRI) nach Struktur und Auslosbarkeit untersucht und ihre mogliche Bedeutung fur die innerartliche Verstandigung diskutiert. b) Mit Hilfe von Sonagrammen, Spektrogrammen und Linienspektren konnen die Laute folgendermasen charakterisiert werden: 1. Schmerzlaut erwachsener Mause : Intensitatsmaximum bei 4 KHz, Aufbau harmonisch, Dauer 120 ± 40 msec. 2. Schmerzlaut von Jungmausen : Intensitatsmaximum bei 12 KHz und 30 KHz, Aufbau harmonisch, Dauer 120 ± 40 msec. 3. Ultraschallaute von Jungmausen : Intensitatsmaximum bei 60 KHz, Aufbau nicht harmonisch, Dauer 80 ± 20 msec. 4. Laute beim Drangen von Jungmausen im Nest: Intensitatsmaximum bei 6KHz, Aufbau harmonisch, Dauer 120 ± 40 msec. 5. Laute von Neugeborenen : Intensitatsplateau von 4-40 KHz, Gerausch mit harmonischen Anteilen, Dauer 140 ± 50 msec. 6. Schmatzlaut von Jungmausen : Intensitatsmaximum bei 2 KHz, Aufbau nicht harmonisch, Dauer 4 ± 1 msec. 7. Verwirrungslaut erwachsener Weibchen: Intensitatsmaximum bei 70 KHz, Aufbau nicht harmonisch, Dauer 40 ± 20 msec. 8. Abwehrlaut erwachsener Weibchen : Intensitatsmaximum bei 4 KHz und 40 KHz, Aufbau bis 10 KHz harmonisch, Dauer 100 ± 20 msec. c) Die Laute wurden aufgrund der Analyse zu drei in ihrer moglichen Funktion verschiedenen Typen zusammengefast : Type I (3, 7) signalisiert Verwirrung und Unbehagen. Typ II (2, 5, 8) soll Aggressionshemmung bei anderen Mausen bewirken. Typ III (1, 4) ist Zeichen eigener Aktivitat bis zur Aggression. Der Schmatzlaut ist in diese Typen nicht einzuordnen. d) Fur die altersabhangige Veranderung des Schmerzlautes wurden zwei Hypothesen diskutiert: Stimmbruch oder Anderung der Motivationslage. e) Die Intensitatsverteilung der Laute wurde mit der Empfindlichkeitscharakteristik des Gehors von Mus muscuclus verglichen. Alle Laute sind fur erwachsene Mause horbar. Die Maxima der Intensitatsverteilung und der Gehorempfindlichkeit stimmen weitgehend uberein.

Field and Laboratory Studies of the Vocalizations of Talapoin Monkeys (Miopithecus Talapoin)

Abstract: The vocal repertoire of talapoin monkeys consists of eleven basic vocal types within which 31 different sounds are described, including all intermediates, "lip-smacking" and branch noises (linked with cohesion calls). Calls are of short duration (1/20s to a few seconds). Some of them have a daily rhythm of emission. Their intensity is variable, the call range varying accordingly from a few to several (more) hundred meters. Talapoin calls are composed either of low-pitched structures, of high-pitched ones, or an association of the two. Seven calls, of the eleven basic types possess low-pitched components (pitch = 0.5 to 1KHz) giving them a common quality, constituting what may be called the "talapoin voice". Two graded systems have been described. One, the most graded, is composed of the aggression-flight vocal types; the second is linked with group cohesion. The important level of gradation within the vocal repertoire of this forest species contradicts the classical concepts which ascribe a "discret" repertoire to monkeys living in a closed milieu. The gradation of the vocal system of a species may be related more to an abundance of social contacts than to the structure of the milieu (multimodality of signals exchanged over short distances). During ontogeny, the vocal repertoire changes in both type and frequency of use. The structural modifications are either continuous, with the growth of individuals, or discontinuous with the sexual maturity of males. Under conditions of average excitation, differential call distribution and their relative frequency according to different individual classes lead us to generalize that the vocal behaviour of a particular class in a group (age, sex and social status) always differ qualitatively and quantitatively from that of other classes. Under conditions of high excitation, differential call distribution and their relative frequency according to different individual classes, lead us to generalize that any individual can give any call type when submitted to adequate stimulation. This difference between the real potentiality of a given individual and actual use in the wild is essentially related to the change of stimulating context as the monkeys grows older. In order to vocalize, the talapoin must receive stimulation which increases its excitation level and directs its response. Furthermore the excitation level does not directly determine a particular vocal type. The vocal response varies according to the situation and is adapted to the stimulus context. We distinguish between stimuli which propagate calls within a social group from those initiating calls. The former are essentially calls of congeners, the latter are more often visual, visual auditory, auditory then tactile. The majority of talapoin calls control the spatial distribution of the troop members in relation to external events (cohesion calls system, aggression-flight calls, mother-young contact calls). Choruses however have a more complex social role which is not completely understood. With a maximal energy concentrated arotmd 0.9KHz, the "lost" calls of young seem to be adapted to penetrate the forest milieu. The presence in certain calls of high-pitched components appears to be linked principally to the rise of the excitation level of the vocalizers. With eleven vocal types, the talapoin has a repertoire comparable to that of other monkeys. It is sympatric with Cercopithecus nictitans, C. cephus, C. pogonias and C. neglectus with which it shares a number of functional categories of calls, features probably imposed by forest conditions (poor visibility, winged predators, ...) examples are the cohesion system, dispersion calls, aggressive alarm to birds). Conversely, the physical structure of calls of genus Miopithecus and Cercopithecus have little in common. The frequent choruses in talapoin seem to be related to a more complex social life than that of the Cercopithecines. The talapoin is differentiated strongly from the sympatric species in the absence of loud calls, the specific characters of call structures and their more graded nature. A similar degree of differentiation is found in the morphological, physiological and eco-ethological traits characterizing the talapoin (GAUTIER-HION, 1970, 1971 a, b). Although some talapoin calls are higher-pitched than those of macaques, there are affinities between the vocalizations of talapoin and macaques : both have graded call systems arising in aggression-flight behaviour and there are similarities in calls with tonal structure: types 2 of talapoin; clear calls of M. mulatta (ROWELL & HINDE, 1962); "coos" and "high-pitched musical notes" of M. nemestrina (GRIMM, (1967); "coos" of M. speriosa (BERTRAND, 1969); "coo sounds" of M. fuscata (GREEN, in press). Finally, there is a close structural resemblance between the "lost" calls of infants talapoin and rhesus.

Examination of Agonistic Behavior By Character Analysis I. the Spider Crab Microphrys Bicornutus

Abstract: 1) The influence of several classes of factors on the agonistic behavior of the spider Microphrys bicornutus were analyzed by character analysis. 2) Static factors (sex, size, color phase, hunger state) were found to have much less influence on the behavior patterns shown in a fight than the behaviors executed by the other animal. 3) The amount of communication between crabs during a fight ranged from 1.00 bits (act 2 to 3) up to 1.57 bits (act 4 to 5). The uncertainty about a given act was reduced by knowledge of the previous act (by the other animal) anywhere from 31% (act 2 to 3) up to 81% (next-to-last-to-last act).

Social Dominance Relationships Between Previously Unacquainte Male and Female Squirrel Monkey

Abstract: The present experiment had two major goals: to determine the social dominance structure among previously unacquainted adult squirrel monkeys of both sexes, and to examine the changes from nonsocial behavioral levels produced by social partners of differing sex and dominance status. Five male and five female squirrel monkeys, housed individually, were first given a series of nonsocial adaptation trials in a novel drinking situation. Their latencies of first drink and of accumulation of 15-sec. of drinking, as well as total drinking and locomotion frequencies and durations, were recorded during these trials. A series of social dominance trials, in which all 45 possible pairs of monkeys were observed, was then administered in the same drinking situation. During these social trials the previously adapted monkeys were scored under the condition of competition for a water incentive. The dominance status of each animal was determined by noting the monkey in each

The interaction of endocrine and experiential factors in the regulation of sexual behaviour in the female guppy Poecilia reticulata.

Abstract: 1. A large proportion of virgin female guppies, Poecilia reticulata, are highly responsive when first placed with actively courting males. This responsiveness wanes over several days if a female is repeatedly exposed to male courtship in a standard test situation (15 mins./day on alternate days). The decline in response occurs even though copulation is prevented by presenting males which have been gonopodectomized (gonopodium removed). Many females become responsive again for a short period(s) some time after the initial period of receptivity at the start of testing. Examination of individual records of females tested for up to 6 weeks suggests that there are cycles in responsiveness which correspond closely to the 20-21 day cycle in receptivity demonstrated in nonvirgin fish (Liley, 1966). The data indicate that a virgin female is likely to be initially highly responsive whatever the stage of her endogenous cycle, hut after involvement in courtship a cycle in responsiveness becomes apparent. 2. Naive virgin females were highly responsive when first tested 2, 10 or 24 days after ovariectomy (Experiment 2). However in contrast to intact fish there was no reappearance of receptive behaviour after sexual activity observed at the start of testing had waned. 3. The rate of decline in responsiveness of naive virgin females is to some extent dependent upon the courtship testing regime (Experiment 3). Most females tested with gonopodectomized males for 20 minutes per day had become unresponsive by the 6th or 7th day; receptivity of females tested at 3 and 6 day intervals declined more slowly but eventually reached the same level as fish tested every day. Testing females with intact males on the first three days resulted in a more rapid drop in female responsiveness. Ovariectomized females were less responsive and their receptively waned more rapidly than intact females. 4. In experiment 4, an attempt was made to determine whether the high initial responsiveness of virgin females was due to the fact that they had been deprived of social stimulation provided by males. Virgin females were tested with gonopodectomized males on 8 consecutive days during which their receptivity declined to a low level. Females were then isolated from males individually or in groups for 1, 2, 3, 4 or 6 weeks before being retested with gonopodectomized males. There was no recovery of responsiveness to a level typical of naive virgin fish in the previously isolated females. Any recovery of responsiveness which did occur was that which might be expected on the basis of each female having the potential to undergo a cycle in receptivity related to an endogenous cycle of approximately 20 days. 5. It is concluded that there is a cycle in receptivity in virgin females which reflects an endocrine cycle in ovarian activity. In addition naive fish show an initially high level of response which is not dependent on the immediate ovarian hormone state and masks the cycle regulated by the ovary. The responsiveness of naive fish habituates as a result of exposure to male courtship. It is suggested that the interaction between the decremental effects (habituation) induced by courtship and the incremental effects of ovarian hormone and short-term incremental effects of courtship may interact in a manner which adjust female receptivity to the social environment, terminating sexual responsiveness once insemination has occurred a number of times.

Le Role De La Reconnaissance Individuelle Dans La Stabilite Des Relations Hierarchiques Chez Xiphophorus (Pisces, Poeciliidae)

Abstract: L'objet de ce travail etait d'etablir experimentalement que la reconnaissance individuelle entre deux poissons pouvait determiner la stabilite; de leurs relations hierarchiques en milieu inconnu. Nous avons utilise 45 paires de Xiphophorus ♂ ♂ (Poeciliidae). Apres une phase pre-experimentale de 24 heures, le poisson dominant () et le poisson domine () de chaque paire etaient transferes ensemble une premiere fois dans un milieu inconnu, ou leurs comportements agressifs etaient enregistres (phase exp. 1). Ensuite (phase exp. 2), les poissons et du groupe Experimental etaient transferes ensemble dans un autre milieu inconnu, alors que les poissons et du groupe controle y etaient transferes avec un congenere inconnu de meme taille, de meme morphologie et de meme experience sociale que leur ancien congenere. 1) Les resultats obtenus au cours de la phase exp. 2 mettent deja en evidence que les poissons et les poissons reagissent de maniere significativement differente dans les paires E et dans les paires C. Les temps de latence des 1ers comportements agressifs et les temps de latence des 1ers comportements de dominance sont plus courts chez les poissons des paires E que chez ceux des paires C. Les poissons des paires E presentent les 1ers comportements agressifs, et les 1eres attaques d'une maniere significativement plus frequente que les poissons des paires C. Les attaques des poissons envers un congenere sont plus frequentes au sein des paires E qu'au sein des paires C. Les comportements agressifs des poissons , et surtout leurs attaques, apparaissent plus frequemment au sein des paires C qu'au sein des paires E; on trouve le meme resultat pour les comportements agressifs de rivalite entre les poissons et les poissons . 2) La mesure de la variable dependante consistait a comparer dans les deux groupes le nombre de comportements effectues par les poissons et par les poissons entre la phase exp. 1 et la phase exp. 2; les resultats obtenus dans les paires C presentent des differences quantitatives extremes par rapport a la stabilite hierarchique qui apparait entre les poissons et des paires E. On trouve ces differences pour: le nombre des attaques, le nombre des nages de menace, le nombre des postures de menace, le nombre des approches des poissons , ainsi que pour le nombre total de leurs comportements agressifs. Le nombre total des comportements agressifs des poissons et des poissons , en tenant egalement compte de leurs comportements de rivalite. Le nombre total de tous les comportements, agressifs et sexuels. effectues par les poissons a et dans chacune des paires E et C. L'experience permet de conclure que deux membres d'une paire se reconnaissent individuellement dans un nouveau milieu, en reagissant tres vite a des differences individuelles qui sont relatives a la morphologie et au comportement d'un congenere. La discussion generale porte sur le role et la fonction ethologique de la reconnaissance individuelle dans la stabilite des relations hierarchiques qu'elle determine chez les Teleosteens.

Electric organ discharge activity of resting and stimulated Gnathonemus petersii (Mormyridae).

Abstract: 1. The electric organ discharge (EOD) activity of 12 isolated Gnathonemus petersii was analyzed by means of interpulse interval histograms (IIH), joint interval histograms (JIIH) as well as by measurements of the instanaeous frequency of consecutive intervals. 2. The IIH of 10 resting fish was characterized by three modes and in two fish by two modes. The higher frequency mode (25-62 Hz) corresponds to burst-like frequency increases (BA) of the EOD, the lower are due to inter-burst activity (IBA). 3. Frequency ranges of modes are remarkably constant during following days and even months. Because of the individual specific position of modes, the IIH renders it possible to distinguish individuals from one another. 4. JIIH computation of the EOD of resting G. petersii reveals that besides a random activity, two types of correlation exist between consecutive intervals (regularization). The first, type I regularization, is characterized by consecutive intervals of nearly equal duration. It occurs in the BA of "trimodal" and "bimodal" fish, and also in the IBA range of "bimodal" fish. The second, type 2 regularization, is characterized by alternating long and short intervals, corresponding to the second and third mode, which are displayed during the IBA of "trimodal" fish. 5. The transition from IBA to BA and vice versa is brief and distinct. The analyses of long periods of activity reveal that the resting G. petersii displays its entire activity spectrum (BA and IBA) in a sequence of about 200 intervals. 6. When stimulated by the discharges of a conspecific or another mormyrid, the EOD activity of G. petersii becomes more regular. Trains of up to 330 equal intervals (type I regularization) were observed. The preferred frequency range for this emission is individual specific and is situated in the minimum between BA and IBA. Its appearence is also characteristic for mechanically stimulated G. petersii. 7. The results described here give evidence that G. petersii emits at least at 6 preferred ranges of frequency.

Mating Speed and Courtship Behaviour of Inbred Strains of Drosophila Melanogaster

Abstract: Three inbred wildtype strains of Drosophila melanogaster, Amherst, Novosibirsk and Pacific differ in mating speed. An analysis of courtship behaviour reveals significant differences between genotypes in the latency and duration of courtship, attributable to differences in sexual response thresholds between males and levels of receptivity between females. There are significant interstrain differences in the proportions of time spent in, and bout lengths of, the principal elements of courtship behaviour of males with virgin females. Virgin females differ from fertilised females in their repertoire of courtship rejection responses and there are significant strain differences in the rates of rejection response. However, rate of rejection was not found to be a good indicator of the female's receptivity. Extrusion forms the characteristic rejection movement of fertilised females and has consequences which are genotype dependent, serving to inhibit further courtship by the male in some strains and to avoid copulation in others. Preening appears to serve as a displacement activity in males which are persistently rejected by females.