bluuebunny/crossref_metadata_2025 huggingface dataset:
Prior Exposure To Light and Pecking Accuracy in Chicks
Authors: Vauclair J. , Bateson P.P.G.
Published: April 2008

Two groups of day-old domestic chicks were exposed to constant white light for one hour. Chicks in one group were socially isolated but unrestrained; the others were unable to move their heads. Later the accuracy of their pecking at millet seed was compared with chicks kept in the dark up to the time of testing. The unrestrained chicks exposed to light were markedly more accurate than the dark-reared birds. The restrained chicks were intermediate in performance between the other two groups hitting seeds more frequently than the dark group but missing more and picking up and swallowing less than the unrestrained Light group. The effects of light on pecking accuracy are interpreted primarily in terms of non-specific stimulation of the visual pathways.
Individual Distance in the Hermit Crabs Clibanarius Tricolor and Clibanarius Antillensis
Authors: Hazlett Brian A.
Published: April 2008

The distances at which individual hermit crabs (Clibanarius tricolor and C. antillensis) showed agonistic behavior patterns was recorded after the animals had been held at one of two densities for a week. 1) Behavior patterns differed significantly in the average distance of separation when they were executed. 2) For almost all patterns, there was considerable variability in the distances at which they were shown. 3) Part of this variance in distances was due to the behavior of the other crab. 4) Density treatment affected the distances at which behavior patterns were shown, the crabs held at the lower density having greater distances. Apparently as a result, lower density crabs lost more interactions. 5) The distances at which behavior patterns were shown were not correlated with either absolute or relative size of the acting crab. 6) Comparison of distances in intraspecific and interspecific interactions indicated very similar behavior in the two species, except that C. antillensis was not as clearly affected by the density treatment.
Sequential and Temporal Properties of Behavior Induced By a Schedule of Periodic Food Delivery
Authors: Staddon J.E.R. , Ayres Sandra L.
Published: April 2008

I. Five hungry rats were exposed to a schedule of periodic food presentation, receiving a single pellet every 30 sec., in an apparatus that permitted drinking, running, and other activities. The development, extinction, and structure of behavior sequences under this regimen was studied in three experiments. 2. All the rats developed a stable pattern of behavior after twenty or so half-hour sessions. The modal pattern was drinking early in the interfood interval, running in the middle, and food anticipation at the end. This temporal pattern was associated with different sequential patterns in different individuals. 3. Elimination of opportunity to engage in one or more activities resulted in an increase in other activities, but the increase was not in simple proportion to their frequency under baseline conditions. 4. In the steady state the sequence of behaviors in each interval appeared to be determined by two main factors: (a) post-eating time, and (b) the "momentum" associated with an ongoing activity. Differences among individual rats appeared to be due largely to differences in the second factor.
Vocal Repertoire of the Mongoose Herpestes Auropunctatus
Authors: Mulligan B.E. , Nellis D.W.
Published: April 2008

Vocalizations of the mongoose II. auropunctatus were found to be composed of twelve categories of calls. Characteristics of each call category were established by means of acoustical analyses of a large sample of vocalizations from a number of animals. The results of these analyses were presented in detail for each category together with brief descriptions of associated behavior. It was concluded that mongoose vocalizations form a unitary system of acoustically distinctive calls that are emitted discretely. It was suggested that this system is one in which the possibilities for discrimination among temporally adjacent calls are optimized. In order to examine this conclusion further, comparisons were made of call spectra, amplitude patterns, and overall amplitude differences. It was found that the spectra of calls that are emitted successively show marked contrast, and that the sharpness of onset and offset patterns is related to the temporal proximity of calls. It was also found that the relative amplitudes of calls that occur within the same behavioral context; either dissonant, consummatory, or agonistic; may contribute to call discriminability. However, there is considerable overlap of the distributions of call amplitudes, and it appears that differences between spectra and amplitude patterns of mongoose calls may contribute more to their discriminability than differences in overall amplitudes. It was suggested that relative amplitudes of calls may reflect levels of behavioral arousal of vocalizing animals.
Self-Sustaining Activities and Reinforcement in the Nest Building Behaviour of Mice
Authors: Roper T.J.
Published: April 2008

EIBL-EIBESFELDT (1961) and THORPE (1963) have suggested that nest-building in various species is reinforced by stimuli associated with the acquisition of a finished nest. HINDE & STEVENSON (1969, 1970) have proposed, by contrast, that individual nest building activities may persist and act as reinforcers regardless of whether or not they lead to nest formation. Evidence for these views is discussed. Five experiments designed to test HINDE and STEVENSON'S view arc described. In Experiments I and 2, naive female mice were given access to hoppers of paper strips for 14 days. Carrying of strips into the nest box declined rapidly to zero as the nests reached completion, but gathering of strips from the hoppers continued at the original level. It is concluded that carrying and subsequent events associated with nest acquisition are not necessary for the initiation and maintenance of gathering. In Experiments 3 and 4, access to paper strips was made contingent upon performance of an arbitrary operant (key pressing). The majority of subjects continued to key press and gather paper after the cessation of carrying, but at a reduced level. Furthermore, key pressing to gather only occurred if the operant-reinforcer distance was very small. It is concluded that gathering per se is less reinforcing than gathering plus carrying and building. In Experiment 5, amount of gathering per reinforcement was varied by using different widths of paper. Number of reinforcements per session was positively related to paper width, providing further evidence that gathering is reinforcing. It is concluded that gathering is at least to some extent autonomously controlled, and that it is a weak positive reinforcer. However the results also suggest that other reinforcing events are present at a later stage in the nest building sequence. Some theories concerning the causation of selfsustaining activities, and their implications for unitary drive theories, are discussed.
The Relationship Between Social Behaviour and the Use of Space in the Benthic Fish Chasmodes Bosq Uianus Lacepede (Teleostei, Bleniidae)
Authors: Phillips Robert R.
Published: April 2008

Chasmodes bosquianus is a bottom-dwelling, blenniid fish. The males of this species utilize and defend enclosed nest sites during the breeding season. This species was selected as an appropriate subject for a study of habitat selection and shelter choice among hole-nesting animals. Two experimental pools were prepared containing different arrangements of two types of objects. These objects were enclosures and open shelters. The former were designed to represent an idealized shelter of the type used for nesting purposes in the field. The latter, which were arranged in rows, were vertical rectangles representing topographical irregularities of the bottom. Placement of the objects resulted in four general types of space in the experimental pools: that adjacent to open shelters, that within enclosures, open space, and that next to the walls of the pool. The blennies utilized the space next to open shelters significantly more and open space significantly less than would be expected on the basis of randomly-oriented movement. In addition, the fish followed routes that passed near the objects, as opposed to crossing open space, as they moved about in the pools. There was a tendency to use enclosures more than could be accounted for by an explanation based on random movement. When the four general regions were compared to one another with respect to use by the fish, somewhat similar results were seen. Space adjacent to open shelters was used significantly more than was open space. Edges were also more heavily utilized than was open space. During short-term (one hour) observations, the fish were found to approach the enclosure (E2) at the junction of two paths more frequently than they did the enclosure (E1) located on a single path. According to one measure, they demonstrated a greater interest in E2 also. However, an explanation for this greater interest based solely on the number of times that the fish approached E2 seems reasonable. During long-term (three-day) observations, the fish were found to utilize enclosures on various paths more than they did an enclosure in open space. No preference among the enclosures on paths of differing complexity was seen.
Determinants of Response of Wolf Pups To Auditory Signals
Authors: Shalter M.D. , Fentress J.C. , Young G.W.
Published: April 2008

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.
The Ontogeny of Ultrasonic Vocalization in Microtus Montanus
Authors: De Ghett V.J.
Published: April 2008

Developmental changes in parameters of ultrasound production were investigated in M. montanus young. The rate of ultrasonic vocalization reached a peak on Day 2 of postnatal ontogeny and declined to zero on Day 15. A similar developmental pattern has been found in several other rodent species. However, the comparatively early peak rate is indicative of a degree of ontogenic precociousness. Other developmental changes, both behavioural and morphological, tend to confirm that M. montanus young are relatively precocious. The duration of ultrasonic vocalizations did not show a significant change across early development. The mean duration for each vocalization sampled was 22.92 msec. The distribution of these vocalizations showed that a considerable number of vocalizations were of very short duration (<30 msec). The developmental changes in the percentage of young emitting ultrasounds began to decline following Day 8 and reached zero percent on Day 15. This decline in the percentage of young vocalizing corresponded to changes in maternal behaviour. Both the rate of ultrasonic vocalization and the percentage of young vocalizing were significantly correlated with the age of the young. Being correlated with age, these parameters of ultrasound production have the possibility of having great communicative value for the purposes of maternal care.
The Ontogeny of Predatory Behaviour in the Golden Hamster (Mesocricetus a. Auratus)
Authors: Polsky Richard H.
Published: April 2008

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.
Social Relationships Among Adult Male and Female Baboons. Ii. Behaviour Throughout the Female Reproductive Cycle
Authors: Seyfarth Robert M.
Published: April 2008

A study of social interactions between two adult males and eight adult females throughout sexual cycling, pregnancy, and lactation revealed three types of "long-term" social bond. 1. Persistent, high-frequency bonds. Two male-female dyads exhibited frequent proximity and grooming throughout the study regardless of changes in female reproductive state. In both cases frequent interaction persisted because of preferences which partners showed for each other. Males in both dyads aided their partners when the partners received aggression more often than they aided others. 2. Persistent, low-frequency bonds. Three females showed a preference for the Alpha male over the subordinate male in all reproductive states. Each female appeared to be attempting to establish a "high-frequency" social bond with the Alpha male. However, all were prevented from doing so by two factors: the Alpha male's preference for one female over all others (see above), and competition from this preferred female. Females competed for access to the Alpha male equally often in all reproductive states. 3. Bonds based on "alternating" f emale preference. Three females associated primarily with the subordinate male during lactation and the Alpha male during sexual cycling. Since the subordinate male served as a focal point for the activities of infants and juveniles, females appeared to benefit from their association with him during lactation. In addition, data suggested that the subordinate male, having established bonds during lactation, attempted to maintain these bonds into the females' periods of sexual cycling. It is hypothesized that the existence of these male-female bonds in multi-male primate groups produces a social structure characterized by a polygynous mating system. Data suggest that male-female relationships are best understood not by examining sexual consortship alone but by considering sexual behaviour within the context of social interactions throughout all reproductive states.
The Ontogeny of Predatory Behaviour in the Golden Hamster (Mesocricetus a. Auratus). Iv. Effects of Prolonged Exposure, Iti, Size of Prey and Selective Breeding
Authors: Richard H. Polsky
Published: April 2008

As an outgrowth of previous experimental work (POLSKY, 1977a, 1977b, 1977c) this paper presents findings which examined the influence of the following variables on the development of predatory behaviour in golden hamsters (M. a. auratus) : (a) prolonged exposure to the prey; (b) the interval between successive prey presentations (ITI) ; (c) the size of prey, and (d) selective breeding. Nymphs of Locusta migratoria served as prey. The basic methodology consisted of testing naive hamsters individually for the capture of a locust in their own home compartment. The principal measure was latency to capture; in addition, in Experiment 3 the frequency of exploration of the prey, withdrawal from the prey, nip at the prey and unsuccessful capture were recorded. Results showed: 1. Increasing familiarization with the prey via prolonged exposure resulted in an increase in the incidence of capture. 2. Latency to capture decreased significantly with repeated testing when the prey was presented at intervals of five or ten days; no significant decrease occurred when the prey was presented at intervals of one day. Further, the response of capture remained intact in established captors after a period of seventy days without the opportunity for capture. 3. Large prey were captured with relatively high latencies by forty day old hamsters; overall, forty day old hamsters, when compared with seventy day old hamsters, also showed a greater frequency of the behaviours associated with capture. 4. Prey capture was susceptible to the effects of selective breeding. The above results were discussed within the framework of habituation (Experiment 1), methodological procedures and the stability of the prey capture response (Experiment 2), the relative size between predator and prey (Experiment 3) and genetic predispositions for capture (Experiment 4). Areas for future research were suggested.
Comportements De Toilettage Et Activation Chez Le Rat Blanc
Authors: Feyereisen Pierre , Blondiau Charles
Published: April 2008

Nous avons observé les comportements de toilettage (grattage, léchage de la fourrure et lavage du museau), ainsi que les autres comportements spécifiques (exploration, immobilité, alimentation) chez 8 rats mâles, de souche Wistar, pendant leur période d'activité. Nous avons mené trois expériences : I, introduction du rat en cage étrangère; II, humidification du pelage; III, introduction d'un objet et diffusion d'un bruit. L'introduction en cage étrangère provoque une augmentation de la durée de l'exploration; la durée des grattages est réduite, celle des lavages de museau accrue. L'humidification du pelage provoque une augmentation de la durée des léchages de la fourrure aux dépends de celle des états d'immobilité. L'introduction d'un objet dans la cage habituelle déclenche une augmentation de l'activité exploratoire, sans modification systématique des autres comportements; par contre, la diffusion d'un bruit provoque une augmentation de l'activité exploratoire, moins nette que dans le cas précédent, mais s'accompagnant d'une augmentation de la durée des léchages de la fourrure et des lavages du museau. On constate ainsi que les stimulations n'ont pas le même effet sur toutes les composantes du toilettage : l'augmentation de la durée de l'exploration réduit la durée du grattage, mais non celle des lavages du museau. En cage habituelle, ces composantes étaient cependant positivement corrélées. Ces résultats invitent à analyser les relations entre le toilettage et l'exploration, ainsi que les différences entre les composantes du toilettage.
Snake Species Discrimination and the Role of Olfactory Cues in the Snake-Directed Behavior of the California Ground Squirrel
Authors: Hennessy David F. , Owings Donald H.
Published: April 2008

This experiment had two objectives. One was to seek evidence for greater caution by California ground squirrels (Spermophilus beccheyi) when interacting with venonnous rattlesnakes (Crotalus viridis), their most important snake predator, than when interacting with nonvenomous gopher snakes (Pituophis melanoleucus), their second-most important snake predator. The second was to examine the role of olfaction in mediating snake-directed behavior by these squirrels, since matry squirrel-snake encounters occur in burrows where visual cues are unavailable. In an illuminated room, we videotaped the responses by eight freely moving ground squirrels to the two snake species; the snakes were presented in large, transparent plastic bags that were either sealed (odor unavailable) or perforated (odor available). The results confirmed our predictions that the squirrels should behave more cautiously toward rattlesnakes than toward gopher snakes, and that olfaction is an important mediator of snake-directed behavior. Although the squirrels approached the two snake species equally often, they attended more to the rattlesnake than to the gopher snake, but remained farther away from the rattlesnake. When snake odor was available, the squirrels spent more time attending to the snakes, approached the snakes more frequently, approached the snakes in elongate postures more often and sand kicked more at the snakes. We proposed the following. 1. The antipredator strategy of snake harassment by California ground squirrels is sensitive to risk, exhibiting attenuation where risk is higher. 2. Olfaction is likely to be even more important during squirrel-snake encounters in the dark, especially in burrows. 3. The ability to recognize snakes on the basis of odor may not depend on prior experience with snakes, and may circumvent difficulties associated with visual detection of snakes.
Filial Imprinting in the Convict Cichlid Fish Cichlasoma Nigrofasciatum
Authors: Thomas F. Hay
Published: April 2008

The convict cichlid fish, Cichlasoyna nigrofasciatum, exhibits extended parental care in both the laboratory and the field. Families of this species were observed in Lake Xiloa', Nicaragua, during part of the breeding season. Young fry (less than 5 days free swimming) could be induced to follow a variety of "dummy" parents when their own parents were restrained at a distance. Older fry fled the dummies in the same manner as they fled predators. Two laboratory experiments were conducted to analyze further the responses of convict cichlid fry to parental dummies. Experiment I demonstrated the following : 1. Fry showed consistent preferences in tests with 5 pairs of mechanically moved dummies. Some of these preferences involve species characteristic cues. 2. Responsiveness to dummies increased over time within a test and over repeated tests. Responsiveness changed non-monotonically with age; those tested at 1 to 3 days free swimming were most responsive, 6 to 8 day old fry were least responsive and 14 to 16 day old fry showed intermediate responsiveness. 3. Preferences were weaker in the older, less responsive fry but were generally in the same direction as in younger fry. Experiment II tested the effects of experience with a particular dummy on the preferences demonstrated in Experiment I. For all ages and for most dummy pairs there was a significant interaction between training condition (preferred vs non-preferred dummy) and preference. Experience with a single dummy also resulted in a general increase in responsiveness to the two dummies in the preference test. The present results are discussed in terms of selection pressures presumed to operate on natural populations of C. nigrofasciatiim and also in terms of research on "imprinting" in precocial birds.
The Development of Play in Cats
Authors: Barrett Priscilla , Bateson Patrick
Published: April 2008

The behaviour of 28 domestic cats from the 4th to the 12th weeks after birth was studied in the presence and absence of their mother. We obtained measures of distress, activity, timidity, distance between mother and kitten, and seven facets of play. The developmental trends in the various measures of play were different, some categories declining in frequency from the 4-7 week period to the 8-12 week period and others notably Object Contact, increasing markedly. These opposing trends and a marked lack of correlation between the measures of play suggest that the outputs of several independent systems are commonly lumped under the general heading of play. The measures of more general aspects of behaviour did not show analogous trends to any of the measures of play and were not correlated with any of them. Cat Contacts in the 4-7 week period was a strong predictor of the same measure in the 8-12 week period. However, none of the other correlations between play in the two age periods is statistically significant, emphasising the marked developmental discontinuity, shown particularly in Object Contacts, between seven and eight weeks after birth. Males made significantly more Object Contacts than females in the 8-12 week period. However, this difference was much less marked when the females had a male in the litter.
The Influence of Habitat Structure On a Nolis Foraging Behavior
Authors: Moermond T.C.
Published: April 2008

1. A series of seven species of Anolis lizards was studied at two sites in southwest Haiti (Ducis, 350 m, and Les Platons, 750 m). Data consisted primarily of continuous observations of individuals. 2. Species differed in their structural microhabitats by the heights and diameters of their perches. Species occupying larger perches and perches higher above the ground tended to confine their movements to a perch surface rather than jumping between surfaces. 3. A series of six "foraging zones" was recognized. These were specific configurations of surfaces which were believed to influence the scanning and movement patterns of hunting lizards. 4. Comparisons of the distributions of distances between scanning locations and waiting times between moves for all species showed patterns consistent with the size and complexity of the area scanned. 5. Differences in orientation in space and with respect to the perch surface were consistent with predicted movement and scanning patterns of particular foraging zones. 6. Plots of waiting time versus distance moved were used to distinguish species with different search strategies but similar rates of progression through the habitat. 7. A stylized diagram of foraging zones as they are connected in a typical habitat was used to compare the niche breadths of the seven species. Species which used a wider array of foraging zones were most widely distributed in southwest Haiti. 8. Although all the species could be classed as sit-and-wait predators, the various analyses revealed consistent site-specific foraging patterns which can be functionally related to the structural configuration of foraging zones. 9. It is suggested that optimal choice of patch types (structural microhabitats) is influenced by the locomotion costs associated with hunting in each patch type. Selection should act to enhance adaptation for site-specific foraging which will reinforce the predictions of the niche compression hypothesis.
The Causal Organization of Climax Behaviour in the Domestic Fowl (Gallus Domesticus)
Authors: Bakhuis W.L. , Van De Nes J.C.M.
Published: April 2008

I. Some aspects were studied of climax (hatching) behaviour in the domestic fowl. 2. The behavioural unit of climax behaviour has two functions: (a) cracking part of the eggshell, and (b) causing the animal to turn some degrees inside the shell. The concomittant movements are described with the aid of film analysis (Section I). 3. On the basis of their causal factors two aspects of climax behaviour can be distinguished: the stereotyped motility pattern of the behavioural unit and the rhytmical occurrence of the behaviour (the movements are repeated every 10 to 30 seconds). The stereotyped pattern only occurs when the freedom of movement of the animal is very restricted, whereas the rhythm already occurs if the animal is not permitted to leave its place while, in addition, its possibilities for postural adjustment are limited (Section 2). 4. After the onset of climax, a constant external stimulation (unbreakable egg and constant ambient temperature) will lead to response waning as a result of habituation, which is a function of (a) time, and (b) the degree of departure from the optimal incubation temperature (Section 3). 5. The degrees of stereotypy of the duration of a unit, proved to be higher than that of the duration of the interval between two consecutive units. 6. On the basis of behavioural and polygraphic criteria and with the aid of drugs it is shown that climax behaviour occurs while the animal is awake or drowsy, but - in contrast to what was thought - not during paradoxical sleep. Paradoxical sleep only occurs when - as a result of the earlier mentioned habituation - the tendency for climax behaviour has become very small (Section 4). 7. The interpretation of the findings is depicted in a relation diagram (Section 5).
Aspects of Sexual Discrimination By Female Siamese Fighting Fish (Bet Ta Splendens Regan)
Authors: Robertson Christine M.
Published: April 2008

I. The responses of female Betta splendens to various stimuli presented behind a transparent partition were recorded. The stimuli comprised live male and female B. splendens, eight motionless model B. splendens, and an empty-tank control. The models consisted of four pairs, one member of which had long male-like fins and raised opercula, and the other, short female-like fins and lowered opercula. The first pair had lifelike colouring; the other three pairs had "aggressive", "submissive", and "reproductive" colourings, respectively. 2. The stimuli and experimental procedures used were the same as those used in an earlier study of sexual discrimination by male B. splendens. 3. The responses to live males and females differed primarily in the amounts of agonistic behaviour shown to each, and in the colour patterns adopted. 4. The colour pattern "Displaying" was never shown to live males, and "Reproductive" was shown only rarely to live females. 5. A Principal Components Analysis was used to analyse the data, and its applicability and accuracy discussed. 6. Four main possible motivational systems were suggested influencing a female's response to a conspecific. These were similar to systems suggested for males. They were: (i) a close display response elicited by a female conspecific; (ii) a mate-or-flee response to a male conspecific (affecting primarily the colour pattern adopted by the female) ; (iii) an overt-aggression response most often elicited by a female conspecific; and (iv) a "curiosity" response indicating interest in a stimulus. 7. The females grouped the live female and live male separately from each other and from all other stimuli. The control was also separated from the model stimuli, which were treated as a single group except for the lifelike and reproductive female models, which were slightly separated from the rest. 8. Females appear to distinguish three classes of conspecific: "displaying female"; "courting male"; and "other". 9. There was some indication that females can discriminate the sex of conspecifics using only fin length and body pattern cues, but, unlike the males, it appears likely that these cues are not the primary ones.
Cultural Evolution in Chaffinch Song
Authors: Slater P.J.B. , Ince S.A.
Published: April 2008

A detailed study has been made of the song types of male chaffinches in the Orkney Islands. Only about 50 pairs of chaffinches nest there and these are mainly concentrated in three woods, with isolated pairs in a number of other places. Recordings of 41 individuals showed that songs fell clearly into distinct types, 16 of which were discovered. Some song types were peculiar to a single individual, while others occurred in the repertoires of many birds. Most were markedly more common in one wood than in others. The most noticeable variation within a song type was in the number of repetitions of syllables in a phrase. This varied significantly between individuals, though not between different woods; variation within an individual was also great. Comparisons between song types suggested ways in which these had diverged during the course of cultural evolution. The main changes seem to have occurred by minor modification of syllables, by changes in the number of repetitions of syllables, by the addition or omission of sections and by the recombination of sections from different song types. Evidence from the variability and distribution of song types argues against song learning in this species having evolved because it enables individuals to transmit information about their identity or about the locality or kinship group to which they belong. Instead it is suggested that song learning arose as a means of achieving a complex vocal output and that the distribution of song types arises partly because mistakes are sometimes made in copying and partly because some individuals disperse more widely than others after song learning.
Joint Nesting in a Digger Wasp as an Evolutionarily Stable Preadaptation To Social Life
Authors: Brockmann H. Jane , Dawkins Richard
Published: April 2008

One suggested evolutionary origin of insect sociality is joint nesting by females of the same generation. Long before selection favoured joint nesting itself, it might have favoured some other incidental preadaptation such as the habit of 'entering' abandoned burrows, found in the usually solitary wasp Splaex ichneumoneus. We have comprehensive economic records of individually marked wasps. There is little evidence of consistent individual variation in nesting success. Wasps often abandon the nests they have dug, and other individuals adopt or 'enter' these empty burrows. 'Dig/Enter' is a good candidate for a mixed evolutionarily stable strategy : digging and entering decisions are not characteristic of particular individuals; the probability of entering is not conditional upon whether it is early or late in the season; there is no correlation between an individual's size and her tendency to dig or enter; there is no correlation between an individual's egg-laying success and her tendency to dig or enter; individuals do not choose to dig or enter on the basis of immediate past success; individuals do not dig and enter in runs, nor do they alternate; wasps do not choose to dig or enter on the basis of how long they have been searching. At one study site digging and entering decisions are roughly equally successful, but at another entering decisions are perhaps slightly more successful. Entering wasps seem not to distinguish empty, abandoned burrows from burrows that are still occupied. As a consequence of indiscriminate entering, two females sometimes co-occupy the same burrow. Co-occupation should not be called 'communal' because the wasps usually share the same brood cell, not just the same burrow. One might expect that wasps would gain some benefit from co-occupying, but they do not, for a number of reasons: only one egg is laid in a shared cell, and obviously only one of the two wasps can lay it; two wasps together do not fetch noticeably more food than one alone; two wasps together are no quicker at provisioning a cell than one wasp alone; wasps sometimes duplicate each others' efforts when they co-occupy a nest; co-occupying wasps often have costly fights. About all that can be said for joint nesting is that it may reduce parasitism. The risk of joint nesting is the price wasps pay for the advantages of taking over an already dug and abandoned burrow. A mathematical model assuming 'dig/enter' as a mixed evolutionarily stable strategy has some predictive success. If the parameters changed quantitatively, the Sphex model could come to predict selection in favour of joint nesting as such. The selection pressures would have to be very strong to overcome the demonstrated disadvantages of co-occupying. Variants of the Sphex model may be applicable to other species, and may help our understanding of the evolution of group living. The theory of evolutionarily stable strategies is relevant not just to the maintenance of behaviour but to its evolutionary change.
Calls as Reinforcers in Bullfinches
Authors: Wilkinson Roger
Published: April 2008

A perch-hopping operant was used to test the reinforcing effect on bullfinches of two classes of their vocalisations. Two reinforcement indices were computed for each individual, there was no correlation between these indices. For four out of six bullfinches tested with loud calls at least one of these indices was significantly high. None of the six bullfinches tested with distress screams had indices that differed significantly from the neutral values. Group data for the median rate of perching during operant levels, test and extinction sessions were interpreted to suggest a pesitively reinforcing effect of loud calls and a punishing effect of distress screams. Problems posed by the use of the perch-hopping operant are discussed.
Time-Budgets of Camargue Horses Ii. Time-Budgets of Adult Horses and Weaned Sub-Adults
Authors: Duncan Patrick
Published: April 2008

Time-budgets of adult and weaned sub-adult horses were studied in a small population of Camargue horses living in semi-liberty. The categories of activities used were: Standing resting, Lying flat, Lying up, Standing alert, Walking, Trotting, Galloping, Rolling and Foraging. The main differences in time-budgets were related to age and to sex : young horses spent more time lying (sleeping), males spent more time standing alert and in rapid movements (trot, gallop), while usually foraging less than did the adult females. During the three years of the study the population increased from 20 to 54 horses and there were considerable changes in social structure as the number of adult males increased. Associated with these developments there were some changes between years in the time-budgets: the most striking of which was a general trend for all horses to spend less time lying. Nonetheless the time-budgets showed a considerable constancy across years and age/sex-classes, especially with regard to time spent foraging. This conclusion may provide a clue as to why horses have an unusual social system based on long term relationships between a male and the females of his harem.
Ritualization and the Evolution of Movement Signals
Authors: Zahavi Amotz
Published: April 2008

It is suggested that the competition among individuals to display their advantage over others and the interest of individuals to display their motivation in a reliable way have been responsible for the evolution of ritualized signals. Small differences between displays can only be perceived against a standard mode of display. Experience is often needed to determine the nature of the variance which is displayed. It is suggested that the stereotyped ritualized species specific movements have evolved as a byproduct of the competition among individuals to display differences and not because of the advantage of displaying specific differences.
The Behavioural State During Climax (Hatching) in the Domestic Fowl (Gallus Domesticus)
Authors: Bakhuis Walter L. , Bour Harry L.M.G.
Published: April 2008

In the last decade it has been proposed that climax behaviour (CB or hatching) in the chick, Gallus domesticus, occurred during episodes of paradoxical sleep (PS). In recent experiments, however, eye opening, a sign of wakefulness, was seen during CB. The present study was designed to decide whether CB is related to PS or wakefulness. Behavioural and polygraphic criteria were employed, and drugs (melatonin and amphetamine) were administered. Melatonin suppressed wakefulness, hatching and PS, but the reappearance of PS did not coincide with that of CB. Amphetamine suppressed PS, but, except for a short period of ataxia, it did not inhibit CB. Lowering of ambient temperature stimulated wakefulness without interfering with CB. Whereas hatching is characterized by vigorous movements, only weak movements could be detected during PS. In view of these findings, it is concluded that CB is related to wakefulness and not to PS. Reports on mammals also indicate that strong movements seen during early stages of development, are not related to PS.
After-Effects of Allogrooming On Proximity and Locomotion in Pairs of Stumptailed Macaques (Macaca Arctoides)
Authors: Goosen C.
Published: April 2008

Laboratory experiments in pairs of stumptailed macaques were aimed at testing the hypothesis that allogrooming behaviour causes a subject to remain close to the partner for a certain period of time. In that case, allogrooming could indeed be regarded as a cohesive force among members of a socially living, natural group. In the experiments, six females were used as subjects; six males were used as partners. Recording concerned various behaviour items (allogrooming, proximity, locomotion, among others) of a subject during her stay in the observation cage. The partner could be present in a compartment adjacent to the observation cage but separated from it by a plexiglass partition sheet. Three experimental situations, each lasting 15 minutes, were used: t) tactile partner situation in which allogrooming could occur through a slit in the plexiglass sheet between subject and partner; v) visual partner situation, with the partner present behind a sheet without slit; and n) no partner situation when the compartment is empty. These situations occurred during two immediately following observations. The order being so as to enable study of 1) effect of differences in immediate situation; 2) changes with time; 3) effects from differences in previous experience. Results confirmed earlier findings that the visual presence of a partner induces in the subject a tendency to be close to the partner and that, if allogrooming is permitted, proximity is enhanced as a consequence of allogrooming. However, there was no evidence in support of the hypothesis that, after allogrooming the partner for some time, the subject would be more in proximity to the male than after it had had no such allogrooming experience. The results showed rather an opposite trend to less proximity and more walking after having groomed a partner for some time, suggesting that the subjects sought contact with the animals in the normal housing quarters which had been left just prior to the beginning of the observations. In view of this, it seems that, if allogrooming acts as a cohesive force between members of a natural group, it docs not act directly upon a tendency to remain close to the (former) allogrooming partner.
Developmental Relationships Among Social, Manipulatory, Postural and Locomotor Behaviours in Olive Baboons, Papio Anubis
Authors: Chalmers N.R.
Published: April 2008

It is argued, that, when studying the development of social behaviour, it is valuable to investigate simultaneously several classes of social behaviour, plus locomotor, postural and manipulatory abilities. Such an approach may reveal that seemingly diverse behaviours have common ontogenetic precursors or depend upon common underlying abilities. In olive baboons, components of feeding and mouthing-and-wrestling are shown to derive from common ontogenetic precursors. Evidence suggests that mounting, riding dorsally, mouthing-and-wrestling and bipedal standing depend upon the ability to maintain postural control under difficult conditions. Some social behaviours, like grooming and presenting, appear later in development than the postural and locomotor behaviours that are used in those social behaviours. The age at which these social behaviours first appear does not seem, therefore, to be a simple function of the age at which the underlying sensori-motor skills first appear. Some vocalizations and gestures are performed in specific contexts, others are not. The contexts which evoke some of them change with age. The rationale for identifying 'precursors' of adult social behaviours is discussed. One behaviour may be the precursor of another by virtue of its form or function, or by virtue of the fact that it is controlled by a mechanism that is the precursor of a mechanism controlling the later behaviour. An early behaviour that is a precursor of a later behaviour according to one of these criteria may not necessarily be its precursor according to another. The extent to which it is valid to split an infant's activities into different classes of social behaviour is questioned.
Sexual Selection and the Evolution of Complex Songs Among European Warblers of the Genus Acr Ocephal Us
Authors: Catchpole Clive K.
Published: April 2008

An attempt has been made to explain why the songs of Acrocephalus warblers have become so complex during their evolution. A considerable body of evidence has implicated sexual selection, and two predictions from sexual selection theory have been tested. First, males with more complex songs should attract females for pairing before their rivals with simpler songs. This prediction has been confirmed, when a strong inverse correlation between syllable repertoire size (song complexity) and pairing date (female choice) was obtained in a population of sedge warblers. No significant correlation was obtained between male arrival date and pairing date. Assuming that the first (usually older) males back should select the best territories, then territory quality appeared to have little or no significant effect upon female choice. The second prediction tested was that due to increased sexual selection pressure, males of polygynous species should have evolved more comples songs than males of monogamous species. Of the six common European Acrocephalus species studied, four are monogamous and two polygynous. The prediction was not upheld, as the four monogamous species had long, complex and variable songs, and the two polygynous species had shorter, simpler and less variable songs. The explanation for this apparent paradox can be found in the different relationships between female choice, feeding ecology and parental investment in monogamous or polygynous Acrocephalus species. In polygynous species, a female must ensure the territory contains enough resources to enable her to feed the young and should base her choice primarily upon territory quality. In monogamous species, a female must select a male who will help her to feed the young, and should base her choice more directly upon male quality. The songs of polygynous species have therefore evolved primarily through indirect (intrasexual) sexual selection pressure, which has produced shorter, simpler and more stereotyped songs more suited to male-male interactions and a territorial function. The songs of monogamous species have evolved primarily through direct (intersexual) selection pressure, which has produced the long, complex and variable songs which females find more attractive.
Sex Ratio and Optimal Male Time Investment Strategies in Asellus Aquaticus (L.) and a. Meridianus Racovitza
Authors: Manning J.T.
Published: April 2008

A. aquaticus and A. meridianus have a passive phase in which the male carries the female for some days before moulting and copulation are possible. The effect of varying male: female ratios (0.5:1; 1:1; 1.5:1) is discussed in this paper. It was found that an increase in the proportion of males led to: a) earlier initiation of the passive phase; b) lower gain rates from paired females; c) an increased tendency for males to leave females; d) a reduction in the strength of the association between the timing of pairing and oviposition. The relevance of these observations to models of optimal female guarding and foraging strategies is discussed.
Communication During Monocular and Binocular Looking in European Jays ( Garr Ul Us G. Glandarius)
Authors: Bossema I. , Burgler R.R.
Published: April 2008

Some aspects of communication during monocular and binocular looking by dominant jays at subordinate cage mates were studied. The probability that each type of looking was followed by attack in the sender was measured in standardized external situations. The signal value of the various signal situations for recipients was measured by determining the probability that they reacted with retreat during signalling. It was found that the higher the likelihood that a signal situation was followed by overt aggression in the sender, the more a recipient reacted with overt escape.