bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agonistic Interactions of Juvenile Savanna Baboons
Authors: Pereira Michael E. 
Published: May 2010

Abstract19 juvenile members of known genealogies in two wild baboon groups were studied over a 16‐month period to compare the ontogeny of agonistic experience and dominance relations for males and females. Juveniles of all age‐sex classes were disproportionately likely to receive aggression from and submit to adult males per unit of time spent in proximity. This pattern intensified with increasing juvenile age. With age, juvenile females more often submitted to unrelated adult females from higher‐ranking families, whereas this was not true for juvenile males. All juveniles received aggression from older group members more often during feeding than was expected by chance. High rates of agonistic interaction with unrelated adult females accounted for old juvenile females (3–5.5 years‐old) interacting agonistically more frequently than male age peers and young juveniles of either sex (1–2.5 years‐old). Adult females were also more aggressive toward females among young juveniles, suggesting that adult females target females among juveniles for aggression and resistance to rank reversal. Within juvenile age groups, males dominated all females and all younger males, irrespective of maternal dominance status. Dominance relations among female age‐peers were generally isomorphic with relations among their mothers. No juvenile targeted any older male for rank reversal. Males targeted all older females, whereas females typically targeted only older females from families lower‐ranking than their own. The strong sexual dimorphism in adult body size in baboons may explain why juvenile males' dominance relations with peers and adult females are not structured along lines of family membership as is true for the less dimorphic macaques. Acquisition of higher agonistic status probably allows juveniles of both sexes to increase their success in within‐group feeding competition during late stages of juvenility, which, in turn, could affect important life‐history traits such as age at menarche and adult body size.
Copulatory Behavior as Courtship Communication
Authors: Dewsbury Donald A. 
Published: May 2010

AbstractIn the copulatory behavior of many species of rodents, mounting patterns with ejaculation are preceded by mounts with nonejaculatory intromissions. Although not directly related to insemination, these intromissions have generally been treated as “copulatory” behavior. If we treat these nonejaculatory intromissions as courtship communication in the tactile modality, new relationships become apparent. Within the context of classical ethology, intromissions can be considered in relation to both proximate dynamics and ultimate effects. Within the sociobiological/behavioral‐ecological context, intromissions can be viewed in relation to manipulation, female assessment and choice, and honesty of communication. The intromissions synchronize, persuade, and orient at the same time as they manipulate the partner.
Simultaneous Discrimination Learning in Chicks: Spatial Representations and Object Characteristics
Authors: Vallortigara Giorgio , Zanforlin Mario 
Published: May 2010

AbstractChicks were trained to discriminate (1) between two boxes of the same colour on the basis of their positions; (2) between two boxes of different colours on the basis of their positions or on the basis of their colours. No significant differences between these tasks appeared. Addition of colour and position improved learning when the boxes were entirely coloured but not when differently coloured discs were placed over the lids of two identical boxes. It is argued that in simultaneous discrimination learning chicks rely primarily on the “relative” position of the goal objects (i. e. in relation to each other) and utilize featural information (colour) to segregate the goal objects as distinct perceptual units. Results also stressed the role of “object characteristics” as opposed to the traditional notion of “cues”.
Foundress Mortality after Worker Emergence in Social Wasps (Polistes)
Authors: Hughes Colin R. , Strassmann Joan E. 
Published: May 2010

AbstractWorker emergence is a watershed in the development of a social insect colony because after workers emerge subordinate foundresses are less critical to the survival of the colony, and may be simply a threat to the egg laying monopoly of the queen. A widely‐held view is that after worker emergence the queen either kills or chases off subordinate foundresses in Polistes, as is the case in many ants. Our examination of changes in subordinate behavior and mortality after worker emergence reveals a more complex picture. Though foundress mortality increased significantly after worker emergence in 5 of 7 populations of Polistes (6 different species), this did not always result from increased queen or worker aggression toward subordinates. Senescence may also play an important role in subordinate foundress mortality. The two species in which subordinate mortality did not increase significantly after worker emergence were characterized by high rates of colony failure due to loss of all workers. This may indicate that subordinates remain in the colony after worker emergence in species where their continued presence is important to the success of the colony.
Non‐random Mating in the Dance Fly Empis borealis: The Importance of Male Choice
Authors: Svensson Bo G. , Petersson Erik 
Published: May 2010

AbstractIn the dance‐fly Empis borealis (Diptera, Empididae), females form swarms to which males, carrying a nuptial gift, come for mating. We examined whether males or females were choosy and/or competed for mates.First, measurements of the size relationships between copulating males and females, nuptial gifts and the swarming females from different swarms were assessed. Second, male visiting time in differently sized female swarms was recorded.Larger (wing‐length) females participated disproportionately in copulations in each swarm, but not for the population at large. Female mating status (virgin/non‐virgin) or proximity to oviposition (egg size) did not influence the likelihood of copulation. No assortative mating pattern was found: male size and size of nuptial gift did not correlate with size of the mating female.The time spent by males in swarms increased with the number of females present and it took longer when males left a swarm without copulation than when doing so. Male visiting time per female was negatively correlated with number of females in swarms. Males more often left smaller than larger swarms without mating.We conclude that E. borealis males discriminate among females but find no evidence for male competition or for female choice. It is still a question to what degree females compete for males.
Can Experience Alter the Avian Annual Cycle? Results of Migration Experiments with Indigo Buntings
Authors: Sniegowski Paul Donald , Ketterson Ellen D. , Nolan Val 
Published: May 2010

AbstractField experiments were conducted during 2 years testing whether premature release on their familiar, perennial breeding territories would cause indigo buntings (Passerina cyanea) to delete spring migration from their annual cycle. In the first year, male buntings were captured on their breeding territories in summer and held indoors for the winter on the photoregime that they would have encountered in nature as fall migrants and winter residents. The following spring they were released at the time buntings begin spring migration from the subtropics. Half were released on their breeding territories, to which they would normally have returned; half were released far to the south. Some of the males released on their territories remained and passed into breeding condition without having migrated, while some of those released to the south returned north to their territories. The results suggest that endogenous or photoperiodic mechanisms controlling the timing and occurrence of migration in this species can be overridden by experience. In the second year we tested alternative explanations for these results. Our second year's results seem to indicate (1) that birds that deleted migration in year one did not do so because of unfavourable weather and (2) that the birds that returned to their breeding sites in year one were actually migrating and not simply retracing their outward journey.
Changes in Nest Defense against a Brood Parasite over the Breeding Cycle
Authors: Briskie James V. , Sealy Spencer G. 
Published: May 2010

AbstractWe measured the responses of nesting least flycatchers (Empidonax minimus) to a model of the brood‐parasitic brown‐headed cowbird (Molothrus ater). A greater number of vocalizations, approaches and threat displays were directed toward the cowbird model than toward a control model of a fox sparrow (Passerella iliaca), suggesting that the cowbird was recognized as a threat. Flycatchers were more likely to give threat displays during laying when the consequences of brood parasitism were greatest; however, the intensity of all other defensive behavior did not change over the nesting cycle. We suggest that least flycatchers remained aggressive throughout nesting because cowbirds were also predators on eggs and nestlings.
An Analysis of Variability in the Feeding Motor Program of the Honey Bee; the Role of Learning in Releasing a Modal Action Pattern
Authors: Smith Brian H. , Menzel Randolf 
Published: May 2010

AbstractSequences of behavior are highly predictable (stereotyped) during some segments and less predictable during transitions between those segments. Statistical characterization of behavior must involve observation of the behavior under different stimulus conditions, which includes how stimuli associated with behavioral releasers come to trigger behavior during learning. For example, the feeding motor program (FMP) of the honey bee Apis mellifera (Hymenoptera: Apidae) during proboscis extension can be divided into three response phases (Rehder 1987). We conditioned honey bees in an olfactory conditioning paradigm with one or several rewarded trials during which an odorant was paired with the sugar‐water unconditioned stimulus (US); the latter elicits proboscis extension and feeding in properly motivated bees. By recording electromyogram activity from one of the muscles that move the proboscis during feeding, we quantified the bees' responses during an unrewarded test with either the conditioned odorant, a different (novel) odorant, or the sugar‐water US. Various parameters of the response phases of the FMP varied in a consistent manner across these experimental treatments, with certain stimuli eliciting stronger, more consistent responses. The different response phases followed one another in time with some variability and statistical uncertainty. For example, the length of an individual licking movement with the glossa was relatively invariant, and may indicate that this parameter can be used to differentiate the FMP into more basic, independent units. Our work shows how learned information may release action patterns in ways slightly different from traditional sign‐stimuli releasers.
Individual Variability, Social Structure and Division of Labour in the Ponerine Ant Ectatomma ruidum Roger (Hymenoptera, Formicidae)
Authors: Corbara B. , Lachaud J.‐P. , Fresneau D. 
Published: May 2010

AbstractThe social organization of an Ectatomma ruidum colony was investigated by individually marking all members and recording their behaviour using an automatic photographic technique. A hierarchical cluster analysis was used to determine functional groups describing this society. We then studied intragroup variability of the individual profiles and showed that there are different, complementary levels of approach to the division of labour in a society.
Foraging Guppies and the Ideal Free Distribution: The Influence of Information on Patch Choice
Authors: Abrahams Mark V. 
Published: May 2010

Abstract10 male and 10 female guppies were each examined foraging for food at 2 separate feeders. The feeders provided food over a wide area so that individuals had equal access to the food. As the proportion of food at a feeder was altered, the proportion of fish using that feeder changed to match the availability of food. Thus, both groups of fish conformed to the predictions of the ideal free distribution (IFD) theory.However, the behaviour of the two groups differed. During these experiments, males continued to shuttle between these feeders whereas females tended to remain at a feeder. Also, the female group conformed less well to an IFD on the first trial of each day but conformed more closely to an IFD in successive exposures to the same food distribution. The male group exhibited no improvement with increasing experience. For both groups, the relative influence of the previous day's experience on foraging decisions declined with time. However, unlike the male group, the female group relied on experience for their initial foraging decisions. It is possible that sampling by males provides the additional benefit of increasing their probability of encountering receptive females. This may account for the difference in information use by the male and female group.
Long‐term Retention of Many Visual Patterns by Pigeons
Authors: von Fersen Lorenzo , Delius Juan D. 
Published: May 2010

AbstractUsing a simultaneous discrimination procedure it was shown that pigeons were capable of learning to discriminate 100 different black and white visual patterns from a further 625 similar stimuli, where responses to the former were rewarded and responses to the latter were not rewarded. Tests in which novel stimuli replaced either the rewarded or nonrewarded stimuli showed that the pigeons had not only learned about the 100 positive stimuli but also about the 625 negative stimuli. The fact that novel stimuli enhanced discrimination performance when they replaced the many negative stimuli indicated that the pigeons had categorized the stimuli into two classes, familiar and less familiar. Long‐term retention was examined after a 6‐month interval. To begin with it seemed poor but a recognition test performed after the subjects had been retrained with a subset of the stimuli after an interval of 7 months confirmed that pigeons are capable of retaining in memory several 100 visual items over an extended period. It is proposed that the initial retrieval weakness was due to a forgetting of the contingencies between stimulus categories and response outcomes. Further tests involving variously modified stimuli indicated that while stimulus size variations had a negative effect on performance, orientation changes did not interfere with recognition, supporting the view that small visual stimuli are memorized by pigeons largely free of orientation labels. The experiment generally confirms that pigeons have the capacity of storing information about a large number of visual stimuli over long periods of time.
Male Defense of the Breeding Cavity and Factors Affecting the Persistence of Breeding Pairs in the Stomatopod, Gonodactylus bredini (Manning) (Crustacea: Hoplocarida)
Authors: Shuster Stephen M. , Caldwell Roy L. 
Published: May 2010

AbstractIn Caribbean Panama, nonreproductive male and female stomatopods are solitary and defend their own coral‐rubble cavities. When breeding pairs form, however, males assume all responsibility for cavity defense. To compare success in cavity defense and defensive tactics among paired and unpaired males, and to examine the tendency for paired stomatopods to exchange their present mates for larger (higher quality) individuals, we introduced same‐sized and 15% larger male, and same‐sized and 15% larger reproductive female intruders to paired and unpaired male residents in a balanced design. Paired males were more successful at cavity defense than unpaired males, evidently because paired males strike intruders more than unpaired males, and because intruders fight less intensely against paired males than against unpaired males. Paired males occasionally attempted extrapair copulations, but showed little tendency to abandon their mates in favor of larger females. Paired females, however, mated readily with intruder males that evicted resident males. Populationwide female breeding synchrony and prolonged female receptivity before oviposition reduce variance in male mating success and may force males to guard the breeding cavity to assure their paternity. Uncertainty about the reproductive condition of intruder females may prevent males from exchanging mates.
Acquired Recognition of Predator Odour in the European Minnow (Phoxinus phoxinus)
Authors: Magurran Anne E. 
Published: May 2010

AbstractNaive European minnows (Phoxinus phoxinus) do not show a fright reaction when they first encounter the odour of a natural predator (the pike: Esox lucius) or the odour of a non‐piscivorous exotic (tilapia: Tilapia mariae). A conditioned fright response to both these odours will however develop if minnows experience them in a potentially dangerous situation, for example, in conjunction with Schreckstoff, the ostariophysian alarm pheromone. Although minnows respond to both odours the reaction to the tilapia odour is reduced. This suggests that a constraint on learning is involved. Olfactory recognition is particularly valuable for detecting predators that hunt in conditions where visibility is poor.
Sperm Competition and Copulation Intervals of the White Spoonbill (Platalea leucorodia, Aves, Threskiornithidae)
Authors: Aguilera Eduardo 
Published: May 2010

AbstractSome aspects of sperm competition were studied in the white spoonbill (Platalea leucorodia) breeding in Doñana National Park (SW Spain). Shorter pair copulation intervals occurred during the prelaying period, when females were subjected to a relatively high frequency of extra‐pair copulations. Pair copulation intervals with an intermediate extra‐pair copulation by the male mate were longer than those without extra‐pair copulation. This result indicates that males need a time of recovery between copulations before they can perform another. Extra‐pair copulations by the females did not affect the length of intervals between pair copulations. There were no differences between the lengths of the intervals between an extra‐pair copulation by the female and the following pair copulation for cases in which the male mate detected an intruder male attempting copulation with his mate and those in which the intruder remained undetected. However, the correlations obtained between copulatory intervals for detected and undetected cases suggest a copulatory response by their mates, although affected by the required recovery time between copulations by the males. Finally, since extra‐pair copulations mainly occurred while male mates were collecting nest material, they engaged in this activity shortly after pair copulations, probably to avoid a last‐male advantage under the sperm competition pressure.
Measuring Dominance and Constructing Hierarchies: An Example Using Mule Deer
Authors: Tomback Diana F. , Wachtel Meryle A. , Driscoll Janis W. , Bekoff Marc 
Published: May 2010

AbstractImportant issues that are still unresolved in the study of animal social groups are how dominance is measured and how individuals are ranked. Based on observations of mule deer (Odocoileus hemionus hemionus), we constructed hierarchies for the same 26 bucks using five potential correlates of dominance and three measures based on the outcome of agonistic interactions. Data for each of six behavior measures were converted to ranks by six different numerical techniques.Different measures of behavior resulted in different hierarchies. This was especially so when the hierarchy based on sparring rates was compared to hierarchies based on other criteria. Although our results showed that dominance is not a unitary concept, several measures of dominance were highly correlated with one another. Thus, one measure, in some instances, may be a good but imperfect predictor of dominance defined by other criteria.For data sets based on index scores or rates of performing behavior, the mean difference and standard‐error difference ranking methods had distinct advantages. Both produced equally weighted ranks that minimized the effects of sampling errors.
Orange Spots as a Visual Cue for Female Mate Choice in the Guppy (Poecilia reticulata)
Authors: Long Kevin D. , Houde Anne E. 
Published: May 2010

AbstractPrevious studies have suggested that orange pigment in the color patterns of male guppies is a cue for female choice. This paper describes a manipulative experiment designed to test this hypothesis. The color patterns perceived by females were manipulated by varying the color of light used to illuminate the experimental aquaria. Orange light dramatically reduces the conspicuousness of orange spots to human observers, and probably also to female guppies. As in previous experiments, female guppies discriminated among males based on differences in the extent of orange pigment, under white, blue, and green light conditions. Under orange light, however, females no longer appeared to discriminate on the basis of orange spots. These results support the hypothesis that orange spots, rather than other correlated characteristics, are a basis for female choice under normal lighting conditions.
Kin Recognition and Maternal Care under Restricted Feeding in House Mice (Mus domesticus)
Authors: König Barbara 
Published: May 2010

AbstractThis study tests the hypothesis that female house mice (F1 generation of wild caught Mus domesticus) should preferentially invest in own offspring if confronted with young of different degrees of relatedness. The maternal behaviour of females with litters of 4 own and 4 unrelated alien young (cross‐fostered at day 1 of lactation) was analysed during a lactation period of 22 days both under ad libitum and under restricted feeding (food was restricted by 20%).Cross‐fostering and restricted feeding had no effect on the amount of time spent nursing until weaning. Under both feeding conditions the females did not differ in their maternal behaviour towards own and alien young: there were no significant differences either in the amount of time spent nursing own versus alien pups or in the time spent licking own versus alien young. Weight gain of own and alien = wild littermates did not differ significantly in mixed litters and was similar both under ad libitum and under restricted feeding. Such indiscriminate behaviour might be adaptive if female house mice prefer to communally nest with a relative and thus improve their inclusive fitness by investing in own and related offspring in a communal nest.Under moderate restricted feeding females could not wean the entire litter but reduced litter size by cannibalizing on average 2.7 pups (75% of the pups were killed when they were 4–8 days old). Females with cross‐fostered litters killed as many own as alien young. This suggests that females cannot discriminate between own and unrelated young if cross‐fostering takes place at day 1 of lactation.Besides testing kin recognition abilities, the experiments also allow analysis of the weaning strategy of females under food shortage. Under restricted feeding, body weight of the females was significantly lower during middle lactation than under ad libitum feeding. Weaning weight of young in reduced litters under food restriction (9–10 g) did not differ significantly from weaning weight of young in litters of 7–10 young, but was lower than that of young in similar sized litters (litter size 6), under ad libitum feeding. The maternal behaviour of cannibalizing some young under food shortage can be interpreted as a weaning strategy which results in the largest number of offspring that can be raised to a minimal weaning weight of 9–10 g. Such a weaning strategy might represent a favourable trade‐off between number and size of young produced.