bluuebunny/crossref_metadata_2025 huggingface dataset:
Sound Production and Associated Behavior in the Jewel Fish, Hemichromis Bimaculat Us
Authors: Rowland W.J.
Published: April 2008

Sound production and associated behavior of the jewel cichlid, Herlaiclarowis bimaculatus was investigated by presenting the subjects with dummies. Thump sounds are associated with a behavior called nodding and probably represent a relatively high level of aggression. Purring is closely associated with lateral display and tailbeating and occurs during the early stages of courtship and attack. The third sound consists of a series of low frequency pulses that are synchronized with the movement of courtship quivering. Individuals direct more behavior toward a dummy emitting thumps and purrs than to a silent one or to one producing pulses of white noise. This indicates that H. bimaculatus uses sound, either alone or in conjunction with other behaviors, for intraspecific communication.
Sound Production By Some Tanganyikan Cichlid Fishes and a Hypothesis for the Evolution of the r communication Mechanisnis
Authors: Nelissen Mark H.J.
Published: April 2008

I. Sound production is studied in Halochromis murtoni, Simochromis diagramma, S. babatiltz, Tropheus moorii, T. brichardi and T. duboisi (Pisces, Cichlidae). The recorded sounds are analysed and visualized as sonograms. 2. As far as communication is concerned, Tropheus is specialized in sound production while Simochromis is specialized in colour patterns. 3. These ways of evolution from an Haplochromis-like ancestor could be correlated with the fact that Tropheus became night-active, and Simochromis day-active.
Time-Budgets of Camargue Horses I. Developmental Changes in the Time-Budgets of Foals
Authors: Boy Vincent , Duncan Patrick
Published: April 2008

The development of the (24 hour) time-budgets of foals was studied as part of a broader investigation of the time-budgets of Camargue horses living in semi-liberty. Nine categories of activity were studied; resting postures (lateral and sternal recumbency, and standing resting), foraging, and postures related to movement and orientation (standing alert, walking, trotting, galloping and rolling). The process of development of the time-budgets as a whole was described by using a multivariate technique, correspondance analysis : variations in time-budgets were largely determined by age, but the environment intervened in mid-summer, when the process of development was slowed down. It was suggested, on the basis of other evidence, that the attacks by horseflies were probably responsible for the arrest in development. It was also found that for some individuals there was also a period shortly before weaning when development was slowed down. Foals developed time budgets closely similar to those of sub-adults (horses 1-2 years older than the foals) very soon (2-4 weeks) after weaning. The changes in the time-budgets involved considerable decreases in the time spent in the lying postures (e.g. lying flat occupied 15% after birth and 2% after weaning), and in movement and orientation (standing alert decreased from 31% to 5% in the same period) while foraging increased from 13% to 62%. It is suggested that the milk supply from their mothers allows the foals to invest time in sleep, and in exploration of their physical and social environment. After weaning, most of this time is spent foraging.
The Roaring of Red Deer and the Evolution of Honest Advertisement
Authors: Clutton-Brock T.H. , Albon S.D.
Published: April 2008

In many large animals, changes in fighting ability within breeding seasons or across the lifetime of individuals are related to changes in body condition but not to obvious changes in size. In situations where a conflict of interests is likely to lead to a fight, we might consequently expect opponents to assess each other on traits which are related to variation in body condition. This appears to be the case among red deer stags. Competing
Display, Timing and Function of Wing Movements Accompanying Antiphonal Duets of Cichladusa Guttata
Authors: Todt Dietmar , Fiebelkorn Anne
Published: April 2008

I. The antiphonal duets of Cichladusa guttata (Turdidae, Aves) are often accompanied by spectacular wing movements. We have analysed the display, timing, coordination and function of this behaviour using sound films, audio and video recordings of free living and captured birds (Figs 1, 2). 2. The vocal duet contribution of the members of a pair appear well coordinated in timing, normally with no overlap of notes. Specific types of duet notes of the male or the female can release wing beats in the male (response time: 380 ± 80 msec.), but not vice versa. Additionally, note utterance can trigger the wing beat start (reaction time 30 ± 15 msec.) in the same bird, which is normally the male (Figs 4, 5, 6, 7, 8). 3. Wing beat performance is also affected by two further variables: "duet activity" and "wing beat periodicity". The duet activity which changes relatively slowly can be estimated from parameters of the behaviour (vocal density, vocal power, etc.). Auditory stimulation with conspecifics songs raises duet activity and thereby facilitates wing movements. This does not affect the "component of wing beat periodicity", which has a cycle length of 540 msec. (Fig. 3; Tab. i). 4. Normally, both wings are moved synchroneously. Experiments with restricted space on one side of a songster showed that wing beats can be blocked unilaterally. While a space restricted wing remained unmoved the other wing operated in full coordination to the duet program. 5. Due to the different affectations wing "escort" is optional. It occurs regularly, but, with high flexibility. When the variables promoting wing beats result in high values, high wing beats occur, when the values are low, low or no wing beats are observed (Fig. 9). 6. (Wing beats are supposed to support the general function described for the vocal duet contributions.) Specific functions discussed for the non-vocal contributions are: focussing and directing of attention (spectacular display via an additional signal channel; avoidance of habituation (optional and flexible occurrence) ; preventing distance signalling from disturbances in the acoustic channel (noise produced by birds singing simultaneously) ; distance measurement by identification of phase shifting between vocal and non-vocal behavioural rhythms.
An Investigation of Song-Based Species Recognition in the Red-Winged Blackbird (Agelaius Phoeniceus)
Authors: Beletsky L. David , Chao Stella , Smith Douglas G.
Published: April 2008

To determine the aspect(s) of male red-winged blackbird (Agelaius phoeniceus) advertising song which function in the transmission of species identity, 74 territorial adult male redwings were exposed to 173 playback experiments of normal and experimentally altered red-wing song during the 1977, 1978 and 1979 breeding seasons. Unaltered red-wing song and altered song containing species-identifying information evoked aggressive behavior from territorial redwings when played through a loudspeaker placed in their territories. A list of red-wing aggressive behaviors was compiled and the males' responses to altered and unaltered song were scored on a "hybrid-index" scale according to the number of times they performed each of the aggressive behaviors during the playback experiment. The results of the study indicate that 1) the ordering of the three song "syllables" did not affect the intensity of the males' agonistic responses to playback song and therefore does not convey species information, 2) the initial two syllables of the red-wing song do not encode the species-identifying information, as these two syllables, alone or in conjunction, failed to elicit fully aggressive responses from the males, 3) the last syllable of the song, a "trill", when presented to the males alone or in conjunction with the other song syllables, evoked fully agonistic responses, suggesting that this trill syllable encodes the majority of species-specific information in the red-wing song, and 4) by playing back increasingly shorter (in duration) sections of the trill syllable to the territorial males, it was demonstrated that the trill must be somewhat longer in duration than 180 msec to function in species identification.
The Effects of Cross-Fostering On the Behavior of Two Species of North American Lemmings, Dicrostonyx Groenlandicus and Lemmus Trimucronatus. Iii. Agonistic Behavior
Authors: Huck U. William , Banks Edwin M.
Published: April 2008

1. The role of the maternal environment in development of species-specific agonistic behavior was investigated by reciprocally cross-fostering two species of lemmings (Discrostonyx groenlandicus and Lemmus trimucronatus). Non-fostered and within-species-fostered (in-fostered) animals served as controls. 2. When adult, cross-fostered male lemmings engaged in more frequent contact social behavior with the foster species than with conspecifics. However, since cross-fostered animals retained their ability to interact with conspecifics in a species-specific manner, cross-fostering appears to have resulted in a broadening of "species identity" to include the foster species. 3. In-fostering reduced the aggressiveness of Dicrostonyx but had little effect on the behavior of Lemmus. 4. Both the intensity and orientation of agonistic behavior were altered as a result of cross-fostering. In Dicrostonyx, a highly aggressive species, cross-fostering resulted in decreased aggression directed at the foster species and increased aggression toward conspecifics. In Lemmus, a less aggressive species, cross-fostering appears to have resulted in a broadening of the response range to stimuli provided by the foster species. When paired with aggressive Dicrostonyx, cross-fostered Lemmus engaged in more frequent and intense aggression than did controls. However, when paired with nonaggressive (in-fostered) Dicrostonyx, cross-fostered Lemmus engaged in less frequent and intense aggression than controls. In contrast, non-fostered and in-fostered Lemmus males had a relatively narrow response range to Dicrostonyx. 5. In general, the results suggested that agonistic behaviour in lemmings is the product of a complex interaction between genotype and maternal environment.
Species Identification of Song By Indigo Buntings as Determined By Responses To Computer Generated Sounds
Authors: Shiovitz Kenneth A. , Lemon Robert E.
Published: April 2008

Species recognition of song by indigo bunting, Passerina cyanea, was studied in playback experiments to territorial males. Experimental recordings included computer simulations and actual bunting sounds. In all, 238 playbacks were carried out with 34 test songs. Actual bunting songs were from Kentucky, U.S.A. and the local population at Chaffeys Locks, Ontario, Canada. One syllable-type from the latter song was repeated to form a unique song, which also served as a model for some simulations. Simulations were of three general kinds: single syllable-type, multiple syllable-type, and general syllable features. The latter series tested general attributes of syllables including sound duration, frequency, amplitude and continuity, with typical ranges and modulation rates. Using 12 variables of response, results were analyzed by univariate and multivariate techniques. Results were as follows: 1. Actual songs were the strongest stimuli (Kentucky then Ontario). 2. General feature simulations all elicited no detectable defense response. 3. Single syllable-type simulations elicited stronger responses as they approached physical attributes of the model. Responses to some simulations could not be significantly discriminated from the model. 4. Manipulation of frequency-time structural detail illustrated that variations of less than about 100 Hz in 10 ms do not affect response. Amplitude variations up to twice the modulation rate in five ms, do not affect response. 5. Multiple syllable-type simulation of the first seven types in the Ontario song elicited responses that were significantly stronger than any other simulations. 6. Multiple syllable-type simulation in which subsegments (unidirectional frequency modulations) were reversed in direction elicited moderate responses. From these results, the following conclusions could be made: 1. As adults, indigo buntings recognize song syllables as approximations of culturally transmitted types. 2. Numerous parameters are used for cues. 3. Effects of some cues are additive. 4. Models of syllable-type distribution, recognition, and learning were discussed.
The Disputed Feeding Behaviour of a Paedophagous Haplochromine Cichlid (Pisces) Observed and Discussed
Authors: Wilhelm W.
Published: April 2008

Aquarium-observations on a new paedophagous haplochromine species (Pisces, Cichlidae) showed that engulfing the snout of a brooding female to extract the brood, is a possible technique of gathering food, as was suggested by GREENWOOD (1959, 1974). Considering morphological information from various authors (GREENWOOD, 1959, 1974; BAREL et al., 1976, 1977) and notwithstanding some doubt expressed by FRYER & ILES (1972) and FRYER (1977), this snout-engulfing may be a widespread technique among the "larger mouthed" paedophages (i. e. in Lake Victoria: 6 out of 8 spp. described plus at least 8 new spp.). Snout-engulfing is the climax of a performance which resembles a fight, during which the paedophage also can force a brooding female to disgorge its brood by chasing and repeated attacks. The origin of snout-engulfing may be thought to lie in a modification of the fighting behaviour of a piscivorous ancestor, hunting on already jettisoned young still guarded by the female.
The Posthatching Consequences of Prehatching Stimulation: Changes With Amount of Prehatching and Posthatching Exposure
Authors: Vince Margaret A.
Published: April 2008

An experiment was designed to assess posthatching effects on the chick's response to the parental alarm call, of different amounts of prehatching experience of the same sound stimulus. Four groups of embryos were given 10, 30, 60 or 120 stimulation trials, a trial consisting of a 51/2 second burst of alarm calls and 25 seconds of silence. After hatching, a group given no prehatching stimulation and all stimulated groups were given 30 test trials. All chicks were tested separately. Response indices used differed; before hatching, heart rate changes were used for this purpose,and after hatching, the number of trials on which the eyes were opened and also vocalisations. Vocalisations were divided into three categories: trills, twitters and cheeps. Prehatching results showed that the heart rate change diminished in successive stimulation trials, but after about the fortieth trial it remained fairly stable, at a low level. Posthatching results showed the effect of prehatching habituation. According to the "eyes open" index the response was maximal at the onset of testing and fell off gradually. It differed very little between stimulated groups, but chicks which heard the sound stimulus for the first time after hatching responded more than those which had heard it while still in the egg. According to the number of calls, the posthatching response was affected by different amounts of pre- as well as by post-hatching experience. In naive chicks it fell at first from the control level and then rose and fell with repetition; in chicks with pre-hatching experience of the sound the rise came earlier. In all cases there was a rise to a peak and then a fall in the number of vocalisations with increased experience, whether this experience was before or after hatching. The increase in calling was attributed to a waning of the suppressing effect of the sound stimulus and the fall to waning of the effect of the sound stimulus itself. This post-hatching waning of the response occurred most rapidly in birds given the most prehatching experience and most slowly in birds which had no prehatching experience of the sound, a difference which was manifested only after the first five minutes of post-hatching testing.
Selective Forces Affecting the Predator Alarm Calls of Vervet Monkeys
Authors: Cheney Dorothy L. , Seyfarth Robert M.
Published: April 2008

Vervet monkeys in Amboseli National Park, Kenya are preyed upon by four types of predator: mammalian carnivores, eagles, baboons, and snakes. Over a 14 month period, adult males and females gave first alarm calls at comparable rates. Both observation on the frequency of alarm-calling and experiments on the duration of alarm-calling indicated that high-ranking adult males and females gave alarm calls more often than low-ranking adult males and females. Individuals who alarm-called most often did not vocalize most often during social interactions, nor did they spend more time than others surveying the habitat around them. There was some tendency, however, for females who alarm-called most often to precede other females in group progressions. Limited evidence suggests that adult males who gave most alarm calls were more likely than other males to have fathered the group's juveniles and infants. Among adult females, however, there was no correlation between number of offspring and frequency of first alarm calls. Females who gave alarm calls most often were not more likely than other females to spend large proportions of observation time more than 2 m from their offspring. Data on a small sample of confirmed predatory attacks suggest that the offspring of high-ranking females may have been more vulnerable than other immatures to predation. Such differential vulnerability may have resulted in part from the tendency of the offspring of high-ranking females to precede other juveniles in group progressions. Vervets of all age/sex classes alarm-called most at those species of predators to which they themselves seemed to be most vulnerable. Adult vervets gave relatively few alarm calls to predators to which their offspring, but not themselves, were vulnerable, even though such alarm calls would have been of low cost to themselves and of great potential benefit to their offspring. While some aspects of the alarm-calling behavior of vervet monkeys are consistent with the hypothesis that their alarms have evolved to benefit kin, in other respects their alarms appear to have the consequence of benefitting only the alarmists themselves. It is likely that both kin and individual selection, acting on an individual's inclusive fitness, have played a role in the evolution of vervet monkeys' alarm calls.
Aggressive Behaviour of Black Skimmers (Rynchops Niger)
Authors: Burger Joanna
Published: April 2008

The aggressive behaviour of skimmers was studied in a mixed species colony of black skimmers and common terns located on a sandy beach in New York. The levels and intensity of intraspecific aggression varied according to sex, season, and time of day. Males engaged in more intraspecific aggression, whereas females engaged in more interspecific defense. These differences suggest that interspecific defense is an appropriate response to the real threat of chick loss due to other birds (of both species). In general, females were defending space and their chicks, whereas males seemed to defend space, their chicks, and females. The aggression observed at any point in the reproductive cycle correlates with the magnitude of the threat.
Pattern and Time Specificity in Vocal Responses of Blackbirds Turdus Merula L
Authors: Wolffgramm Jochen , Todt Dietmar
Published: April 2008

Male blackbirds (Turdus merula) were confronted with modified and unmodified playback copies of their own songs presented within the birds normal territories (Fig. 1). The vocal responses of the birds were recorded and correlated to the playback songs in respect to pattern specificity (song matching) and time specificity (distinct latencies). The following results were obtained: 1. The initial element of a song played a key role. If it was erased or masked by a pre-element the birds did not match the playback copies. In contrast erasure of the second element or the rest of the song following the second element did not affect song matching (Figs 3, 4). 2. The second element had an additional effect. The matching preference increased with a shortening of the pause between the first two elements, it decreased when the second element was substituted by an alien element (Figs 2, 3, 4). 3. A series of initial elements (identical or different element types) led to an inhibition of song matching. In contrast, copies including a doubling of the first two or three elements had a supernormal effect (Figs 4, 5). 4. Three types of song responses could be discriminated: in type I responses (latency: L = 0.1 s) the birds did not match the stimulus; in type II responses (L = 0.25-0.8 s) song matching was preferred; type III responses (L > 1 s) showed no time specificity towards onset of playback songs, but still a preference of song matching (Figs 6, 7). 5. In general, late matching responses (type III) were less preferred than rapid ones (type II) but the effects of different song modifications remained the same. 6. In type II responses, the temporal triggering of the reply and the recognition of the heard song class were not completely linked. In contrast to the neglectable influence of the third elements they were well able to trigger a reply (Fig. 9).
Minimising Errors in Splitting Behaviour Into Bouts
Authors: Slater P.J.B. , Lester N.P.
Published: April 2008

Some problems in using log survivor functions to split behaviour into bouts are outlined. It is argued that it is usually best to choose that bout criterion which leads to the fewest within and between bout intervals being assigned to the wrong category. A way of doing this is illustrated and other possible criteria are considered. The influence of misassignment on data analysis is discussed and it is argued that where this is substantial analysis in terms of bouts may not be useful.
Geographic Similarity and Year-To-Year Retention of Song in the Clay-Colored Sparrow (Spizella Pallida)
Authors: Knapton Richard W.
Published: April 2008

The existence of dialects, individual variation in song within a population, and song retention from one year to the next were studied in populations of clay-colored sparrows in Manitoba and Ontario. Dialects were not found to exist in populations 12 km or 300 km apart in Manitoba. This was not because all songs were similar between the various areas, but because there were large variations among individuals within the different populations. An isolated population 2000 km distant in Ontario had only one characteristic different from the Manitoban populations; this difference is interpreted as arising from founding effects. Some factors which aid the development of dialects exist; males retained song types from one year to the next, and they showed a high rate of return between years on the study areas. However, in spite of potential isolating mechanisms (geographic separation and habitat differences), dialects did not develop, and it is argued that this results from an absence of song copying and cultural transmission of song pattern, and a lack of return of young to their natal area.
The Dawn Chorus in the Great Tit (Parus Major): Proximate and Ultimate Causes
Authors: Kacelnik Alejandro , Krebs John R.
Published: April 2008

The dawn chorus of the great tit can be interpreted from a functional point of view in terms of the following factors. (i) Climatic and other physical conditions in the early morning are unfavourable for foraging and favourable for acoustic communication. (ii) Overnight accumulation of territories favours early morning invasion by potential settlers. (iii) The combination of (i) and (ii) favours early morning territorial defence, including song. A laboratory experiment designed to investigate the proximate causes of allocation of time by territorial great tits to foraging vs. territorial activities (including song) showed that birds are more responsive to intruders when food availability is low. We discuss the relevance of our results to the dawn chorus in other animals and in other geographical regions.
Territoriality, Body Size, and Spacing in Males of the Beewolf Philanthus Basilaris (Hymenoptera; Sphecidae)
Authors: O'Neill Kevin M.
Published: April 2008

1. Males of the digger wasp Philanthus basilaris defend and scent-mark small mating territories. There is a high rate of turnover of males on territories on both a daily and seasonal basis due, in part, to predation on territorial males and the large number of usurpations of territories. 2. The outcome of aggressive interactions on territories is determined by size differences among males, rather than by their status as resident or intruder. As a result, territory holders are larger on average than non-territorial males. The latter, however, remain in the area and attempt to usurp territories or replace residents that have abandoned their perches. Evidence suggests that larger territorial males are also less subject to predation by robberflies and conspecific females. 3. The type of mating system of this species resembles those defined as leks. Males established territories in groups of up to about 50. Nests of females were not found within aggregations of territories. There is a high potential for polygyny due to the lack of maternal care of offspring, dominance interactions which consistently favor larger males and result in intense sexual selection, and asynchronous emergence of females combined with potentially longlived males. Although large males are dominant, no body size related spatial structure to the aggregations could be identified. Aggregations of territories often occur in the same location from year to year, even though males live for only one season.
Relationships Between Social Structure and Response To Novelty in Captive Jackdaws, Corvus Monedula L. Ii. Response To Novel Palatable Food
Authors: Katzir Gadi
Published: April 2008

The response of captive handreared jackdaws, Corvus monedula, in six groups, to novel palatable food was tested. i) Each group was tested as a whole. ii) Novel food (cockroaches, Periplaneta americana) was provided in a dish in a test room which the birds could enter from their home aviary at will. Ordinary food was simultaneously provided ad lib. iii) In each group one or two birds were most active in the approach and the feeding on the novel food, as measured by frequency of initiation of bouts of approach and feed and/or duration of feeding. iv) Birds that initiated most feeding bouts were the most likely to spend longest durations of feeding on the novel food. v) In all six groups the "initiators" were of mid of low social rank. vi) Socially top ranking birds were distinguished from all others by the combination of two features; (a) they did not act as initiators, and (b) they were not the last to peak in their duration of feeding on the novel food. These results are similar to those obtained for the response of the jackdaws to novel space. It gives further support to the idea that individual response to novelty is related to the social structure. Mid or low ranking individuals may benefit from being more exploratory, while top ranking birds may benefit more by being more conservative.
Variability in the Responses of Black-Billed Magpies To Natural Predators
Authors: Buitron Deborah
Published: April 2008

Encounters between black-billed magpies (Pica pica) and a variety of natural predators were observed during 3 breeding seasons in Wind Cave National Park, South Dakota. How a magpie responded to a potential predator appeared to depend on (1) the type of predator and the threat it posed to magpie eggs, nestlings, fledglings, and adults; (2) the behavior of the predator; and (3) the reproductive stage of the magpie. Raptors were the most frequently encountered potential predators, with magpies reacting more strongly to falcons than to hawks. Reactions to crows and squirrels were most frequent and intense during laying and incubation, while raptors in flight and coyotes were responded to most vigorously during the second half of the nestling period and the first two weeks of fledgling. Perched raptors were almost always mobbed vigorously. Diving to within 2 m of a predator appeared to be effective in driving it away. The roles of chasing and alarm calling were less clear, but in addition to alerting mates and offspring to danger, such behavior would impede efficient hunting by the predator and so might contribute to its departure. Only one successful act of predation was observed, but the evidence suggested that owls, hawks and falcons were responsible for most fledgling and adult mortality. No clear cases of nest predation by crows or squirrels occurred, but some clutches of eggs and broods of young nestlings disappeared. Although mates usually mobbed predators together, males were slightly more active, possibly because males were larger and because females were often occupied in the nest with incubation and brooding. Observations of wild fledglings and hand-raised magpies suggest that magpies have an innate fear response to a variety of stimuli and that fledglings gradually learn what to continue fearing from parents, other magpies, and their own experiences. I suggest that although parental investment theory may be basically correct in predicting that young increase in value to their parent as they approach independence, a variety of other factors may affect anti-predator behavior, such as (1) the types of predators likely to be encountered and the relative danger they pose to different age classes; (2) the ability of the parents to successfully drive off a particular predator; (3) the ability of the parents to re-nest that year; (4) the likelihood that a pair will be able to fledge young the following year.
Motivation of Harassment of Matings in Stumptailed Macaques
Authors: Niemeyer C.L. , Chamove A.S.
Published: April 2008

A group of 12 wild-born adult stumptailed macaques and their 10 offspring, housed in an outdoor enclosure at Stirling University Primate Unit in Scotland, was intensively studied over two years and 271 copulations to account for vigorous harassment of mating pairs observed in this species. Three hypotheses were tested: that harassment (a) functions to protect the mating female from aggression by the mating male; (b) functions to reduce the reproductive potentials of mating monkeys; and (c) is motivated by possessiveness of a mating individual. The Protective Hypothesis was rejected. The Reproductive Potential Hypothesis received support only in that any male dominant to a mating male could consistently interrupt copulations. All other harassers not only failed to disrupt copulations, but harassed mating kin more than comparable non-kin. The Possessive Hypothesis received support: (a) females directed more harassment at matings of females, but not males, with whom they were most highly affiliative; males showed no such tendency; (b) the more desired contact partners, dominant adults, received more harassment than less "attractive" individuals; and (c) post-mating interactions indicated that normally strong bonds between mating monkeys and their usual companions were disrupted by the matings. In matrilineal Old World monkey groups, since the most enduring bonds arise between females, the function of harassment by females appears to be reinforcing access to allies, kin, and dominant individuals.
The Responsiveness of Newly Born Clun Forest Lambs To Odour Sources in the Ewe
Authors: Vince Margaret A. , Ward T.M.
Published: April 2008

Two groups of newly born lambs, twelve ("suckled" lambs) having been fed by the mother and aged between 3 and 21 h, and twelve ("unsuckled" lambs) taken at birth with minimal olfactory experience of the dam, were tested with the smell of three substances taken from the mother and three taken from an alien ewe. The substances were inguinal wax, wool and milk. Changes in heart and breathing rates and in behavioural activity were used as indices of the lambs' response. Results showed that lambs in both groups responded most markedly to the smell of wax. Behavioural responses consisted of head movements, oral activity and bleats and in unsuckled lambs were given significantly more to the smell of maternal, than of alien wax. Unsuckled lambs responded more to all six odour sources than did suckled lambs. In unsuckled lambs the rate of breathing rose significantly during stimulation with the smell of maternal wax and this response was also significantly different from that given by unsuckled lambs to alien wax. In suckled, but not unsuckled, lambs there was a significant rise in the heart rate during and after stimulation with maternal wax, but not in response to any other odour source. Results are discussed in terms of "teat-seeking" behaviour in newly born lambs and the question whether the unsuckled lambs' capacity to discriminate their own mother's from alien wax depends on prenatal olfactory experience.
Social Organization of Small Heterosexual Groups of Green Swordtails (Xiphophorus Helleri, Pisces, Poeciliidae) Under Conditions of Captivity
Authors: Beaugrand Jacques P. , Caron Jean , Comeau Louise
Published: April 2008

Sixteen populations, each of four male and four female green swordtail fish, were observed in 54 litre tanks separated into two unequal volumes by a partition allowing swimming from one area to another only at the surface. Each population was observed on 2-4 occasions, making a combined total of 50 observation periods of 2 hours each. Chase-right orders, spatial positions as well as several agonistic and epigamic behaviour units were noted during each period of observation. Males and females apparently form distinct hierarchies which are perfectly linear and transitive in 68% and 42% of the cases respectively. Some dominance structures are incomplete, but no intransitivity is noted. Alpha males are much more aggressive than their isosexual subordinates. In females, the frequency of aggressive behaviour appears to be more proportional to the social rank of the initiator, but the number of chases received from other females is the best indicator of rank in the female hierarchies. Alpha males are responsible for 80 % of all sexual activity and have privilege to behaviour leading to insemination with a high probability in 85 % of the cases. Females are not courted according to their position in the female hierarchy, nor to their size. In the two-compartment situation of the present study, which allowed spacing-out and visual isolation of the individuals, the alpha males occupied the larger area of the aquarium in the company of the four females while the three subordinate males were restricted to the smaller area, unaccompanied by any females. This spacing-out pattern emerged with neat regularity from the data and was apparently caused and maintained by aggressive behaviour, especially by charges, initiated by the alpha male toward male rivals. However, it is not evident that the behaviour of the alpha male should be neatly qualified as territorial defence, since specific-area-linked dominance was never realized in the present study. The social scheme most readily applicable to the present social and spatial organization is the "one male to several females" system or monarchistic male hierarchy, in which one male becomes very dominant over the others, occupies the larger area and is also the sole individual to court the females and to attempt insemination (haremic). These results support the sociobiological theorem that to dominate is to have priority of access to the necessities of life and reproduction.
Visual and Acoustic Display in Uca Mordax and U. Burgersi, Sibling Species of Neotropical Fiddler Crabs. Ii. Vibration Signals
Authors: VON HAGEN Heinrich-Otto
Published: April 2008

The sibling species of fiddler crabs, Uca mordax and U. burgersi, which are very similar in respect to morphology and many traits of their waving display (see part I of this study), were studied bioacoustically in Trinidad (W.I.). When recording their vibration signals (mainly in the laboratory) it was, at the same time, possible to directly observe the animals' underground activities. The dominant vibration signals of the two species were found to be extremely different: males of U. mordax emit rapping sounds ("drumwhirls") by ambulatory percussion, whereas males of U. burgersi produce "howling" sounds (with a varying number of harmonics) by cheliped convulsion, i.e. inconspicuous quivering movements of this appendage. Similar interspecific differences exist in the fainter vibration signals of females. Each of the two species is capable of producing other signals in addition to the prevalent ones mentioned: U. mordax can emit cheliped vibrations as well (though percussive ones) and U. burgersi can also produce ambulatory "drumwhirls". From these and other basic similarities and from comparisons with recordings of burgersi sounds from Colombia and allopatric populations in Florida, the common starting-point and the different evolutionary pathways leading to the two species-specific termini of acoustic display are reconstructed. The extreme differences that were found for the sympatric situation in Trinidad are regarded as an example of character displacement. Apparently, the acoustic communication system of these crabs is much more affected by character displacement than the visual one.
Forced Copulation as a Reproductive Strategy of Male Lesser Scaup: a Field Test of Some Predictions
Authors: Afton Alan D.
Published: April 2008

I presented evidence that sperm transfer can occur during forced copulation (FC) under natural conditions, and tested predictions of the fertilization strategy hypothesis, with field data from a marked population of lesser scaup breeding in southwestern Manitoba. As predicted, males directed FC attempts at fertilizable females and seemingly had tactics that increased their effectiveness in inseminating such females. Males selected older females (the more productive) when attempting FCs in 1 year of the study. FC rates were highest in the morning when chances of successful fertilization were probably highest. FC rates were positively correlated with annual variations in female reproductive effort and performance, but the exact nature of the relationship requires further study. Mate-and nonmate-defense by males and other behaviours which probably function as anticuckoldry tactics were observed. Contrary to BARASH'S (1977a) prediction, paired males attempted FCs more frequently than did unpaired males. Although pair formation through mate-switches is probably a more profitable strategy than FC for unpaired males, FC may be an important "last resort" strategy for older, experienced unpaired males late in the season. In general, my results provided strong support for the male fertilization strategy hypothesis.
Reproductive Behaviour and Ecology of Symphodus (Crenilabrus) Ocellatus, a European Wrasse With Four Types of Male Behaviour
Authors: Taborsky Michael , Hudde Barbara , Wirtz Peter
Published: April 2008

The temperate, gonochoristic wrasse Symphodus ocellatus was studied in the field (Corsica). The largest males defend an area within which an average of 3-5 successive nests are built from algae. These brightly coloured, paternal, territorial males (T-males) spend between one and two thirds of their time during the 10-day nest cycle building the nest and fanning. They eat very little at this time, although they consume eggs and invertebrates in the nest, including egg predators. T-males occasionally take over neighbouring nests. Nest acquisition has two functions: nourishment (2/3 of all take-overs) and reproduction (1/3). T-males practising the latter save over 1/3 of the time of a complete nest cycle. Most take-over males that acquire nests solely for nourishment fan it, as do their reproducing counterparts. Small males with inconspicuous female colouration roam about and try to fertilize eggs parasitically when females spawn in T-males' nests. There are usually several of these "sneakers" around successful nests. Medium sized males (smaller than T-males and differently coloured) also cuckold T-males, but often display submissively to them. They participate in nest defence against conspecifics and in interactions with females, with an average effort that even exceeds that of the nest owners. Males displaying this "satellite behaviour" feed much less than sneakers and remain at one nest during most of its spawning phase. They are more tolerated by T-males than are sneakers, although they are on average only half as far away from the nest and thus much more frequently encountered by the T-male. The proportion of time a male spends as a satellite depends on its size. Usually only the largest accessory male at a nest behaves in this manner, though smaller males occasionally perform elements of satellite behaviour. Satellites never participate in nest building, courtship, direct broodcare or interspecific defence, nor do they take over abandoned nests. A fourth type of male, similar in size and appearance to sneakers and satellites, refrains from reproduction in a specific year. These males are perhaps future T-males. All females seem to participate in reproduction every year. They spawn repeatedly in the same nest over one day, but often change nests and T-males on successive days. Male tactics are roughly determined by size, but there are still choices to be made, such as when to give up a nest which has little spawning success, whether to build a nest or to attempt a take-over, or when to reproduce and whether to adopt the sneaker or satellite roles. The simultaneous occurrence of T-males, satellites and sneakers within a species is compared to a few other examples of diverse taxa.
Distance To Cover, Visual Obstructions, and Vigilance in House Sparrows
Authors: Lima Steven L.
Published: April 2008

House sparrows (Passer domesticus) feeding away from protective cover decrease their level of vigilance as group size increases. In contrast to recent studies, however, their level of vigilance decreases when feeding farther from cover or in the presence of visual obstructions. These apparent discrepancies reflect the potential complexity in the response of vigilance to various aspects of the risk of predation; scanning need not necessarily increase with the risk of predation. Much work as to the exact nature of the factors influencing vigilance remains to be done before we can fully understand its response to various environmental manipulations.
Perceptual Imprinting: Stimulus Preferences, Age Effects, and Genetic Canalization
Authors: Kovach Joseph K.
Published: April 2008

The separate and interactive influences of genetically variable unconditional stimulus preference, age effects, and genetic canalization were studied in relation to perceptual imprinting in Japanese quail chicks (C. coturnix japonica). The chicks were drawn from populations subjected to 21 generations of bidirectional genetic selection for unconditional approach preference between blue and red stimuli. They were tested for age and stimulus effects in perceptual learning from synergistic and conflicting exposures to the genetically preferred and genetically unpreferred colours. Unselected quail chicks were tested as genetic controls, and the qualitative influences of exposures to colours were controlled by comparable exposures to white and other preference-wise neutral stimuli. The results indicate robust and developmentally stable gene effects in the quail's unconditional colour choices, developmentally persistent but episodically variable learning from exposures to colours of genetically variable preference values, and systematic genotype-environment interactions. Discussion focuses on the canalizing role of genetically variable unconditional stimulus preferences in the early developmental of behaviour.
Home Range Size, Overlap and Exploitation in Domestic Farm Cats (Felis Catus)
Authors: Mertens Claudia , Turner Dennis C.
Published: April 2008

Home range size, overlap and exploitation in domestic farm cats is examined. Data were collected on the 11 adult cats (5 O'O'; 6 ♀♀) living on 3 Swiss farms throughout 1984; 8 of the cats were fitted with radio transmitters. Census-point and focal animal methods of data collection were employed. From area-observation curves we concluded that our home range maps (and sizes) were good approximations of the areas utilized by the animals in 1984. Correlations existed between range size and 1) the number of map-fields visited per day by the cat (+); 2) the percentage of observations at the primary home (-); 3) the proportion of the range visited each day (-); and 4) the percentage of map-fields used only by one cat (+, but only for males). The general pattern of social organization found elsewhere was confirmed: males were generally more tolerant of each other than females (based on range overlap), especially considering animals living on different farms. Animals from the same primary home showed considerable range overlap. Male ranges were much smaller than expected (not even twice as large as the female ranges, whereas they should have been about 10 times the size, based on all other studies). These results are discussed in connection with male reproductive strategies, cat density and patterns of range utilization. And lastly, we could demonstrate coordination of hunting activity in time and space by two adult individuals on one farm (sibs), adding to the list of behavior patterns illustrating facultative sociality of house cats.
Communication By Agonistic Displays: Ii. Perceived Information and the Definition of Agonistic Displays
Authors: Paton D.
Published: April 2008

1) Great skua (Stercorarius skua) interactions were studied in the club areas of colonies on Hoy and Fair Isle. Attention was centred on reactor response to postures given by actors which did not attack or escape after displaying. 2) The regression of the reactor's escape probability on distance from the actor was analysed for Facing and Not Facing orientations of the actor. 3) Responses shown to the postures Oblique/Long Call/Wing-raising (Facing and Not Facing), Neck Straight/Bill Straight (Not Facing) and Neck Straight/Bill Straight/Long Call (Not Facing) were similar, and depended on distance, rather than the posture. This rules out the possibility that these postures constitute distinct threat signals. However, Neck Straight/Bill Straight (and Neck Straight/Bill Straight/Long Call) Facing showed a distinct pattern of response which indicated that they formed a (single) threat signal. 4) This pattern was consistent across the different colony-year samples. 5) It was concluded that the great skua behaviour patterns analysed here acted to define different situations rather than providing information about signaller intentions.
Communication By Agonistic Displays
Authors: Paton D. , Caryl P.G.
Published: April 2008

1. Great skuas Stercorarius skua use a range of displays in agonistic interactions in the club areas of their breeding colonies. We examine whether these displays allow reliable prediction of the signaller's future behaviour. 2. Skuas were studied on Noss, Fair Isle and Hoy over 3 seasons. Data from 5 colony-year samples were analysed separately. For each interaction, the display used, the signaller's action after displaying, and the receiver's response, were recorded. 3. Attack could be predicted less well than escape. However, variations between samples were so great that neither the absolute nor the relative probabilities of attack or escape could be reliably estimated from the display. 4. The bird that initiated the interaction was more likely to attack or stay, and less likely to escape, than its rival, but the relative probability of attack or escape after different displays was consistent, for birds in the two roles, within a sample. 5. By correlating the responses of the receiver with information about the signaller's future behaviour encoded in its display, it is possible to find whether this information is transferred in the interaction. There was variation between samples in the pattern of correlations, and no consistent evidence of information transfer could be found. 6. The data are discussed in the light of CARYL'S (1979) earlier discussion of models from games theory. The results show that a test of consistency is crucial for any hypothesis about the message carried by a particular display. They indicate that skua displays do not communicate intention in these interactions.