bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flock Size and Foraging Decisions in Central Place Foraging White Storks, Ciconia Ciconia
Authors: Alonso Javier A. , Alonso Juan C. , Carrascal Luis M. , Muñoz-Pulido Rodrigo 
Published: April 2008

Abstract
We studied the foraging decisions of six individually marked white storks at a breeding colony in central Spain. Storks behaved as central place foragers, gathering in flocks to feed. Travel distance and patch residence time were positively correlated with the size of the foraging flock, but not with patch quality as estimated by the instantaneous food intake rate at the patch. Patch residence time was also positively correlated with travel distance to the patch, flock size being constant. In larger flocks individuals benefitted from a decrease in vigilance time and thus an increase in time spent actively feeding, which enabled birds to bring back to the nest a higher load size. These results suggest that storks followed simple rules of thumb based on flock size, rather than on the more complicated food availability estimations required by central place foraging models. We suggest that flock size could be the main cue used in foraging decisions by white storks and could be a simple rule for many other flock foraging species.
Sexual Responsiveness of Female Canaries To Song Bout Organization
Authors: Kreutzer Michel , Vallet Eric , Nagle Laurent 
Published: April 2008

Abstract
Recent experiments demonstrated that in oscine species, 1) Some special sequences of multipartite songs convey more sexual information than others and 2) Stimulus change or switching is often associated with intersexual interactions. We looked for an influence of these two song cues in common domesticated canaries. Female canaries were tested for their sexual copulation solicitation display (CSD) in response to the playbacks of different strings of song sequences from males of the same breed. In order to induce habituation, three monotonous strings were created: A.A.A.A.A.A; B.B.B.B.B.B and C.C.C.C.C.C. (repetition of the same song sequence). In order to manage disrupt of habituation by stimulus changes, four types of strings including two types of song sequences were created: B.B.B.A.A.A., A.A.A.B.B.B., C.C.C.B.B.B. and B.B.B.C.C.C. We found that a monotonous repetition of the same sequence leads to habituation when the sexual potency of the sequence is high (sequences A and B) and that song sequences may greatly differ in eliciting sexual displays (A >B>C). Subsequent stimulus change may elicit an immediate response recovery. But such a disrupt of habituation occurs only if a prefered sequence follows a non prefered one. We discuss prominent parameters that may have influenced female sensitivity and responsiveness to string organization in domesticated canaries.
Use of Trill Vocalizations To Coordinate Troop Movement Among White-Faced Capuchins: a Second Field Test
Authors: Boinski Sue , Campbell Aimee F. 
Published: April 2008

Abstract
The white-faced capuchin, Cebus capucinus, employed a specialized vocalization, the trill, to coordinate troop movement at La Selva, an Atlantic wet-forest study site in Costa Rica. We analyse the contexts in which this intra-group vocalization was emitted, including responses elicited from other group members. A cumulative 26.6 hours of continuous samples and 3,314 spectrograms (including 1,295 trills) were analysed from a study troop with 16 focal subjects. These results generally corroboratc the conclusions of a comparable field study of white-faced capuchins at Santa Rosa, a Pacific coast dry-forest site in Costa Rica (BOINSKI, 1993, Amer. J. Primatol. 30, p. 85-100). At both sites, (I) trills were closely associated with the initiation of movement by a stationary troop in a specific direction. (2) Trills were emitted at a much higher rate in the leading edge of a travelling troop than in following positions. (3) Individuals often reinforced the efforts of other troop members to coordinate troop movement. (4) Lack of consensus among troop members over the travel route was evident. (5) In rare instances trills were employed in tactical maneuvers suggestive of intentionality and the ability to anticipate behavioural effects. Differences in the usage of trills at these two sites were also detected. (1) At La Selva all troop members, with the exception of infants, used trills in the coordination of troop movement, whereas at Santa Rosa marked age, sex and rank distinctions in the extent of participation were apparent. (2) Capuchins at Santa Rosa altered the trajectory of travelling troops with trills, even reversing directions, but not at La Selva. These disparities may follow from differences between the sites in the extent of visual and auditory contact typical among troop members, social structure, susceptibility to predation, and possible genetic variation.
Behavioural Patterns in Baboon Group Encounters: the Role of Resource Competition and Male Reproductive Strategies
Authors: Cowlishaw Guy 
Published: April 2008

AbstractFemale Between Group Contest BGC competition for limited and monopolizable ecological resources such as food and water is the conventional explanation for behaviour during primate intergroup encounters. It is further advocated as an explanation for the evolution of social groups. This paper tests this explanation (H1) against two competing hypotheses. These are that patterns of intergroup interaction represent (H2) BGC mediated through males or (H3) male reproductive strategies. Four predictions are generated from these hypotheses and tested with data from two sources: (1) a cross-population Papio baboon literature survey and (2) a population-specific chacma baboon Papio cynocephalus ursinus case study. This population consisted of five groups (four habituated) in the semi-desert Pro-Namib region of Namibia. The predictions were: (P1) female OR male aggression dominates encounters, (P2) the number of females OR males determines the outcome of encounters, (P3) there is frequent aggression OR tolerance at resources during encounters, and (P4) males chase females away from their group OR into their group through herding during group encounters. Tests of these predictions using both databases failed to support H 1 or H2, but did provide evidence in favour of H3; namely female aggression was absent, male aggression was infrequent and directed towards either infants of other groups or females of their own group in herding episodes, and encounters with displacements tended to occur only rarely and mostly where resources were either non-monopolizable or absent. These results imply that BGC is not currently a selective force maintaining baboon social groups in either the study population or other populations across Africa. In order to further investigate the complex behavioural patterns observed in baboon intergroup encounters, data describing the demography and relatedness of groups and individuals are required.
The Effect of Schistocephalus Solidus (Cestoda: Pseudophyllidea) On the Foraging and Shoaling Behaviour of Three-Spined Sticklebacks, Gasterosteus Aculeatus
Authors: Barber Iain , Huntingford Felicity A. 
Published: April 2008

AbstractIn this paper we review recent experimental work on the effects of the parasite Schistocephalus solidus (Cestoda: Pseudophyllidea) on the feeding behaviour of three-spined sticklebacks (Gasterosteus aculeatus L.). We also discuss how increased feeding motivation and subsequent altered foraging behaviour may be a mechanism for parasite-associated changes in the shoaling behaviour of infected sticklebacks. The presence of S. solidus plerocercoids in the body cavity constricts the stomach, increases the handling time for large prey and consequently reduces the profitability of such prey for infected fish. This is reflected in a switch in dietary preference from large to small prey in the laboratory and in altered stomach contents and impaired nutrient reserves in the wild. By altering their hosts' nutritional state by direct competition for nutrients from digested food (and possibly indirectly by altering diet and reducing competitive ability) and also by altering the fishes' appearance, such parasites have the potential to alter the costs and benefits involved in joining a shoal of conspecifics. Experimental work on the shoaling decisions of S. solidus-infected sticklebacks supports this hypothesis, and such behavioural modification is discussed in the context of the manipulation hypothesis of parasite transmission.
Recruitment Screams of Pigtail Monkeys (Macaca Nemestrina): Ontogenetic Perspectives
Authors: Gouzoules Harold , Gouzoules Sarah 
Published: April 2008

AbstractIn several species of nonhuman primates screams given by victims of attack elicit interventions from allies in the social group. In the present study, the screams of 16 pigtail macaques (M. nemestrina) under three years of age were assessed with respect to production and contextual usage. Data obtained from these animals three years later were compared with those from the previous period for evidence of changes in usage and production. It was hypothesized that these monkeys (8 males and 8 females), when three years older, would show patterns of contextual usage and production for agonistic screams that were more similar to those of adult animals. For control and comparison, 10 monkeys (9 females and 1 male) who had been older than three years of age during the earlier study were also sampled during the subsequent period. Calls of all subjects were assigned to one of four agonistic contexts (defined by the severity of the aggression and the dominance rank of the opponent) using discriminant functions that had been generated from the earlier data. While the successful classification rate improved for the 16 subjects that were originally three years of age or younger, no significant change was found for screams of the 10 older control monkeys. The probabilities with which screams of the 16 younger subjects were assigned correctly to context (a measure of call production) also were significantly higher during the second period. No such change was evident in the calls of the 10 control subjects. Data from the earlier study period had suggested that, among juveniles, females appeared to be more proficient than males in both the production and usage of these calls. During the second period of study, the proportion of calls that was classified correctly increased significantly for both males and females. The results of tests comparing the proportion of correctly classified calls for individuals revealed no differences between males and females during the second period, confirming similar results for pooled data analyses. Furthermore, there were no significant differences between males and females in the assignment probabilities with which calls were correctly classified. These results suggest that, with age, the younger monkeys became more proficient in the contextual usage and production of screams.
Many Mates Make Male Pipefish Choosy
Authors: Berglund Anders 
Published: April 2008

AbstractIn the sex-role reversed pipefish Syngnathus typhle males search for mates, and prefer to mate with large rather than small females. When mate density was experimentally manipulated, males exerted a mate choice only under high mate density, whereas no mate choice could be demonstrated under low mate density. Hence, when mates are infrequently encountered, males reduce the costs associated with an extended mate search by accepting females that otherwise would have been rejected.
Responses To Conspecific Advertisement Calls in the Green Frog (Rana Clamitans) and Their Role in Male-Male Communication
Authors: Bee Mark A. , Perrill Stephen A. 
Published: April 2008

Abstract
We investigated vocal communication between males in a central Indiana population of the green frog, Rana clamitans. Three playback experiments were conducted. In the first test, we broadcasted a single-note and a multiple-note conspecific advertisement call and a control call (Acris crepitans) to calling males. In response to the conspecific stimuli, males increased the number of calls made per minute, increased note duration, lowered the dominant frequency in the call, and often approached the speaker platform. In a second playback test, designed to examine changes in the sound pressure levels of response calls, we broadcasted a conspecific single-note advertisement call and the control call to calling males. Males in this test lowered the intensity of their responses to the conspecific stimulus. We take these altered response calls to be encounter calls used in the vocal defense of a territory during agonistic male-male interactions. We examine the function of these calls and discuss their possible role in communication between males. In the third test, we broadcasted a second type of conspecific multiple-note call and the control call. In their responses, males increased the number of the second multiple-note calls. The multiple-note stimulus used in this test failed to elicit the agonistic responses of the first two conspecific calls. The role of this second type of multiple-note call in male-male communication remains unclear.
Maternal State Induction in Female Spiders By the Young
Authors: Roland C. , Gundermann J.L. , Horel A. 
Published: April 2008

Abstract
Females of the spider species Coelotes terrestris must successively attend their egg sacs, then their young, in the course of their reproductive cycles. The various activities have been shown to depend on defined reproductive states. The purpose of the present work is to clarify whether maternal responses can be experimentally induced outside normal periods. Females, which spontaneously do not attend spiderlings, were either kept with groups of spiderlings for one week, or kept in isolation for the same duration. Females exposed to spiderlings adopted the behaviour of provisioning to the young and were more tolerant towards them, while no behavioural changes were noticed in isolated females. This phenomenon is consistent with the relative behavioural flexibility exhibited by this spider species.
Aggression, and the Acquisition and Function of Social Dominance in Female Anolis Carolinensis
Authors: Andrews Thomas J. , Summers Cliff H. 
Published: April 2008

Abstract
Female green anoles, Anolis carolinensis, were paired in terraria to investigate behavioral components of social interaction. Resources (perching sites, prey, and males as potential mates) were limited to assess their importance to cohabiting females. During interaction, paired females exhibited aggressive social behavior which contributed to the development of dominant-subordinate relationships. Dominant status and its relationship to differential resource acquisition was defined primarily by frequency of displacement of another female. Along with displacement, dominant females also had increased frequency of assertion displays, challenge displays, attacks and biting (Figs 1 & 2). Subordinate females were displaced more often and assumed submissive postures. No differences were found between dominant and subordinate females for perch site selection, body color or in prey capturing latency or success (Figs 3 & 4). Perch site elevation was not different between dominant and subordinate females, but was significantly lower than males. The color of paired females was not different unless males were present, in which case dominant females were darker. Paired females also respond differently to courtship display (Fig. 5). Dominant females responded with displays significantly more often than subordinate females to male courtship, indicating receptivity. The role of dominant-subordinate relationships among female A. carolinensis may include courtship and reproductive success as an important component, with consequences for the outcome of aggressive and reproductive social interactions with males.
Female-Female Competition and Male Mate Choice in Barbary Macaques (Macaca Sylvanus)
Authors: Kuester Jutta , Paul Andreas 
Published: April 2008

AbstractDue to a strong breeding synchronization, the Barbary macaque is a likely candidate for female competition for access to mates, female reproductive suppression, and male mate choice. The present study evaluated the significance of these factors for the mating system of this species. Female competition was analysed from focal observations of 19 out of 59 potentially reproductive females in their conception period. Ad libitum recorded sexual interactions of all animals were used for an analysis of male mate choice. The focal females were aggressive towards females once per 6.1 h and received aggression from females once per 3.8 h. However, they were three times more frequently the target of male aggression (once per 1.2 h), whereby the aggressor was often the momentary sexual partner. Rate of aggression received from males and females was not related with female rank. Females of all cycle stages disturbed sexual contacts, whereby the intruder was dominant to the target in most episodes (86 out of 100). Intruders more attractive than their targets were most successful in terminating the sexual association of their target, but success of intrusions was low and not related with female rank. The intruder copulated with the former partner of her target in only 5 intrusion episodes. Rate and date of conception and infant survival was not related with female rank, indicating that aggression against females during the conception period and intrusions into sexual contacts did not impair reproduction. Therefore, female
Relation Between Behaviour and Physiological Maturation in a Ponerine Ant
Authors: Fénéron Renée , Durand Jean-Luc , Jaisson Pierre 
Published: April 2008

Abstract
In the ponerine ant, Ectatomma tuberculatum, workers pass through successive functional stages over the course of their adult life. This behavioural ontogeny from brood care to foraging activity appears to be closely related to glandular changes. Intranidal workers have growing or mature ovaries, while extranidal workers have degenerated ovaries but a well-developed reservoir of the poison gland. Our study, which was based on individual marking and multidimensional analyses, evidenced that the behavioural differences recorded among workers of a same age class are related to at least one physiological parameter. It means that variations in the course of the functional stages as compared to a basic age polyethism, may be partly explained by physiological maturation. We suggested then to substitute the term of 'age polyethism' by a more appropriate one, such as 'maturation polyethism'.
Do Female Chacma Baboons Compete for a Safe Spatial Position in a Southern Woodland Habitat?
Authors: Ron Tamar , Henzi S. Peter , Motro Uzi 
Published: April 2008

AbstractIn this study troop of chacma baboons (Papio cynocephalus ursinus) at Mkuzi Game Reserve, Zululand, South-Africa, it is suggested that risk of predation and competition over safe spatial position had more importance and effect on female behaviour than did competition for food. Only 6.4% of all agonistic events were over food patches and no significant correlation was found between a female's dominance rank and proportion of time spent feeding, feeding bout length or diet composition. Parameters of reproductive success, such as inter-birth intervals and infant mortality were not correlated with female dominance rank. Female mortality, however, was related to dominance rank and all of the five females who disappeared during the study were low-ranking. Four of the five females disappeared after troop fission. There is circumstantial evidence supporting the suggestion that predation by leopards is the main cause of mortality of females at Mkuzi. High levels of female aggression were recorded, with almost no occurrences of support coalitions. Most of the aggression took place among similar ranking females, or was directed by the top ranking toward the lowest ranking females. Most of the female-to-female agonistic encounters were in a social context, and more than half were over a spatial position next to other adult troop members. Aggression among females increased after troop fission. It is suggested that the higher-ranking females may be better protected from predation, through access to more central spatial positions in the troop. Indeed, a positive correlation was found between a female's dominance rank and the time spent next to other adult troop members. It may be that avoiding food competition by keeping larger distances from others, while foraging, was translated in lower ranking females to a cost of higher predation risk.
Agonistic Behaviour in Larvae of the Northwestern Salamander (Ambystoma Gracile): the Effects of Kinship, Familiarity and Population Source
Authors: Walls Susan C. , Conrad Charles S. , Murillo Michelle L. , Blaustein Andrew R. 
Published: April 2008

Abstract
We examined whether kinship and familiarity influenced the agonistic behaviour of larvae from three different populations of the Northwestern salamander, Ambystoma gracile. We tested for differential behaviour (1) between individuals within each population; (2) among the three populations; and (3) between non-siblings originating from the same, versus a different, pond. Within each population, larvae failed to discriminate conspecifics based upon either their genetic relatedness or their familiarity. However, individuals from one population displayed significantly more agonistic behaviour than did larvae from the other two populations. Neither familiarity nor the population source of individuals, by themselves, influenced the ability of individuals to discriminate between unrelated larvae from the same, versus a different, pond. Rather, familiarity and pond of origin interacted to alter larval behaviour in a non-additive fashion. This familiarity x pond interaction suggests that, under some conditions, larvae could distinguish between conspecifics from their own, versus a different pond; i.e. larvae significantly reduced acts of aggression and submission toward unrelated individuals from a different pond, but only when they were familiarized. The apparent lack of kin discrimination in A. gracile contrasts with the discriminatory abilities of most other amphibians that have been investigated. Thus, scrutiny of the life history and ecology of this species may provide important clues as to the selective forces operating on the evolution of kin discrimination in larval amphibians.