bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationships between Mother and Infant Red‐necked Wallabies (Macropus rufogriseus banksianus)
Authors: JOHNSON C. N.
Published: May 2010

Young red‐necked wallabies first look out of the pouch at 6 months of age, and may begin to leave it for short periods a month later. Their mothers do not exclude them from the pouch until they are 9 or 10 months old, and in the intervening time they may spend quite long periods abroad, but return to the pouch when alarmed.

During their first month after permanently emerging from the pouch, infant wallabies spend much of their time alone in dense vegetation, while their mothers feed and rest elsewhere. Over the subsequent four months to weaning the young spend most, but not all of their time with their mothers; infants use small home ranges and rarely accompany their mothers into open areas. Sons follow their mothers more closely, and spend more time with them, than daughters do. While together, mothers and offspring interact with a low frequency; suckling bouts are rare but quite long. Mothers and young usually flee in different directions if alarmed, and find one another again later.

Other species of macropods as small as, or smaller than red‐necked wallabies also display behaviour comparable to the hiding of the newborn young of many species of ungulates, while the larger kangaroos of more open habitats have following young. This trend in the occurrence of hiding and following parallels the distribution of the same traits in ungulates, except that hiding is less strongly and less widely expressed in the macropods. This difference between the two groups is probably due to the marsupial mode of reproduction: young macropods of a developmental stage comparable to newborn ungulates can evade predation by entering the pouch, while the infant ungulates must either hide alone or follow their mothers.
Foraging vs. Territorial Vigilance: the Selection of Feeding Sites by Male Great Tits (Parus major L.)
Authors: YDENBERG R. C.
Published: May 2010

Captive male great tits (Parus major L.) were given a choice of feeding on a branch from which the site of a recent simulated intrusion could be monitored, or feeding from a branch with a higher prey density but from which surveillance was impossible. The males spent more time on the unprofitable surveillance branch after an intrusion had been simulated compared to trials with no simulated intrusion. This resulted in a lower feeding rate. Males of many songbird species shift to different feeding sites during the period of territorial defense, and this experiment supports the interpretation that these shifts are made to accommodate territorial vigilance.
Sex Ratio Adjustment in a Seasonally Breeding Primate Species: Evidence from the Barbary Macaque Population at Affenberg Salem
Authors: PAUL ANDREAS , KUESTER JUTTA
Published: May 2010

Presented are data on secondary sex ratio in a large population of semifree‐ranging Barbary macaques (Macaca sylvanus) at Affenberg Salem. Examined were 569 births in five social groups with regard to demographic parameters, maternal age and rank. Significant differences were found between the secondary sex ratios of high ranking and low ranking females. A higher proportion of male offspring was born in the high ranking class, while both groups did not differ in fecundity rates. A detailed analysis of the reproductive cycles of 73 females showed a significant shorter interval between the end of conceptional estrus and birth in male infants and also a significantly earlier onset of deturgescence of anogenital swelling when males were conceived. These results strongly suggest that the differences in the secondary sex ratio are not due to differential abortions but rather to pre‐conceptional control of sex via timing of mating in relation to ovulation.
Soil Consumption of Two Groups of Semi‐free‐ranging Lemurs {Lemur catta and Lemur fulvus)
Authors: GANZHORN JÖRG U.
Published: May 2010

Soil consumption of two Malagasy lemurs, Lemur catta and Lemur fulvus was observed in an enclosure simulating a natural habitat at Duke University Primate Center (Durham, USA). Soil eaten by L. catta contained more Na than random soil samples. Concentrations of the four major minerals in soil eaten by L. fulvus did not differ from random samples. L. fulvus stopped soil ingestion in summer when they ate large amounts of foliage rich in K and Mg, also in winters after being fed with MgCl2. It is suggested that, in this study, soil was consumed in relation to its mineral content and not for physical properties related to its structure. Some non physiological factors that might influence food selection are discussed.
Individual Variation in Anti‐predator Responses in the Three‐spined Stickleback (Gasterosteus aculeatus L.)
Authors: HUNTINGFORD FELICITY , GILES NICK
Published: May 2010

Inter‐population differences in stickleback anti‐predator behaviour in responses to predation risks are now well established (HUNTINGFORD 1982; GILES & HUNTINGFORD 1984). This paper reanalyses this data in search of individual behavioural differences in the exploration of a novel environment and escape strategy shown by sticklebacks when stalked by a hunting pike (Esox lucius). 8 factors (accounting for 70% of the variance in the original data) emerge from the analysis and significant sex and population effects are described. Factors 1 and 2 correspond to predator investigation and the level of boldness shown towards pike. Factors 3, 4 and 5 separate the escape response into three distinct tactics adopted by sticklebacks when being stalked by the pike. These behaviour groupings are independent of the activity of the stickleback before the presence of the pike is detected. Factors 6, 7 and 8 were comprised of activities (use of open water, of weed beds and of the cover provided by the bottom of the tank) which load heavily for both the periods before and after the sticklebacks reacted to the predator. These groupings may represent different anti‐predator tactics adopted by individual sticklebacks.
The Modulation of Worker Activity by the Vibration Dance of the Honeybee, Apis mellifera
Authors: SCHNEIDER STANLEY S.
Published: May 2010

The influence of the vibration dance of the honeybee on the behaviour of non‐foraging‐age workers was examined. Compared to controls, vibrated non‐foraging‐age workers spent more time active during 15‐min observation intervals. This increased activity resulted primarily from increased time spent in the tasks associated with brood cells and cell inspecting, although the time spent performing other tasks, such as those associated with food cells and cell capping, was also enhanced. The dance also increased the number of different tasks performed. The vibration dance may therefore play an important role in regulating the activity of non‐foraging‐age bees.
Song Repertoires of American Warblers (Parulinae): Honest Advertising or Assessment?
Authors: LEMON R. E. , MONETTE S. , ROFF D.
Published: May 2010

We consider a number of hypotheses explaining the social use of song repertoires by territory‐holding of male American warblers (Parulinae). Males vary by species in having from one to several songs that are used in station singing. In the latter case the songs are clustered into subsets or modes. The songs (= modes) vary in use by season and territorial position. Much of the organization appears to reflect a duality of function relative to mate attraction on the one hand and to interaction between males on the other. We focus especially on two hypotheses of male interaction that appear to make opposite and testable predictions, these being whether the males use the songs to honestly advertise their claims on the territory, or whether they are assessing their relative resource‐holding potentials.
Oral Fertilization in a Mouthbrooding Cichlid Fish
Authors: MROWKA WOLFGANG
Published: May 2010

It has been hypothesized that in maternal mouthbrooding cichlids the conspicuous markings on the male's anal fin function as “egg‐dummies” by fooling the female into snapping at them, thereby inhaling sperm and assuring fertilization of the eggs in the mouth. I show experimentally in Pseudocrenilabrus multicolor, an East African maternal mouthbrooder, that indeed oral fertilization takes place. Nevertheless, external fertilization plays a significant role, too.
Sperm Number, Spermatophore Weight and Remating in the Bushcricket Poecilimon veluchianus
Authors: Reinhold Klaus , Von Helversen Dagmar
Published: May 2010

The influence of the intermating interval on sperm number and spermatophore mass was examined in the bushcricket Poecilimon veluchianus. Males that remated after 1 d transferred about 50% of the sperm, but significantly more than 50% of the weight of spermatophores than males that remated after 2 d. Assuming a constant rate of replenishment of sperm and spermatophore material we concluded that available spermatophore material but not available sperm number influences remating interval in P. veluchianus males.
Behavioral Interactions of Two Solitary, Halictine Bees with Comparisons among Solitary, Communal and Eusocial Species
Authors: McConnell‐Garner Janice , Kukuk Penelope F.
Published: May 2010

Laboratory behavioral experiments were conducted with two solitary, halictine bee species, in the genus Lasioglossum, to examine the nature of behavioral interactions between non‐nestmate females. The experimental design of this study was identical to previous work on both a communal (Kukuk 1992) and a eusocial Lasioglossum species (Breed et al. 1978), thereby providing data for comparison of female‐female interactions in species within a single, very large genus that exhibit different sociality. Both solitary species exhibited low levels of aggressive behavior yet nearly all females were reproductively active, as determined by subsequent dissections. Neither ovarian width nor size was associated with aggression in either species. Interspecific comparisons reveal large differences in cooperation and aggression among the four congeneric species. The communal species exhibits significantly more cooperative and less aggressive behavior than all other species suggesting that communal social behavior in Lasioglossum is not phenetically intermediate between the behavior of solitary and eusocial species.
The Influence of Chemical Stimuli from Predators on Precopulatory Pairing by the Amphipod, Gammarus pseudolimnaeus
Authors: Mathis Alicia , Hoback W. Wyatt
Published: May 2010

Many amphipod crustaceans exhibit precopulatory mate guarding. Field samples of the amphipod Gammarus pseudolimnaeus indicated that pairs were positively size assortative. Receptive individuals readily formed pairs in the laboratory and the latency to formation of precopulatory pairs was decreased under threat of predation. In addition, females and, under conditions of extreme danger, males that formed pairs were significantly smaller when under the threat of predation. Amphipods distinguished between chemical stimuli (aquarium water) from predatory and nonpredatory fishes and between chemical cues from fish predators (trout) that had recently eaten conspecific amphipods vs. those fed a control diet of pelleted commercial fish food. These data indicate that chemical stimuli associated with predators can influence reproductive behavior of amphipods. The results also suggest the hypotheses that: 1. search time may be costly in terms of probability of predation; and 2. small pairs may be safer from predation than larger pairs.
Crypsis and Behaviour in Sandhoppers: Antipredator Effectiveness in the Water
Authors: Ugolini Alberto
Published: May 2010

Predation experiments in tanks with the two‐banded bream fish Diplodus vulgaris and the sandhopper Talitrus saltator demonstrated that: 1. some specific behaviours; and 2. crypsis of the back have an antipredator function. They reduced by one‐half the predatory attacks in the water, under artificial conditions.
Species Differences in Spatial Memory Performance on a Three‐dimensional Task
Authors: Balda Russell P. , Kamil Alan C. , Bednekoff Peter A. , Hile Arla G.
Published: May 2010

Three species of seed‐caching corvids were tested in a spatial, three‐dimensional analog of the radial maze. The apparatus consisted of five artificial trees, each with six branches. A wooden feeder could be attached to each branch. Each feeder contained a hole that could hold a pine seed. During the first 40 trials of acquisition testing, all three species improved rapidly with nutcrackers and pinyon jays performing at higher levels than scrub jays. Testing was then interrupted for 31 d. After the interruption, the two species of jays continued to improve but the nutcrackers did not. This species performed with only modest accuracy through the remainder of the experiment. Mixed‐interval testing was done at 10, 60, 180, and 300 min. All species declined in accuracy with increased retention interval. However, at 10 and 180 min, pinyon jays performed significantly better than scrub jays. This is the fourth spatial memory task in which pinyon jays have out‐performed scrub jays. The difference in performance between these two species provides more evidence for divergence in spatial cognition as a function of dependence on cached food.
Male Competition, Mating Success and Female Choice in a Seasonally Breeding Primate (Erythrocebus patas)
Authors: Chism Janice , Rogers William
Published: May 2010

Mammals with restricted breeding seasons often show brief but intense bouts of male competition for mates and male reproductive success has been attributed to male competitive abilities, with the most aggressively successful males able to control access to fertile females, or with females choosing to mate with such males. We studied male competition, mating behaviour and female mate selection in patas monkeys, a primate with a restricted breeding period. We observed two habituated patas groups in Laikipia District, Kenya, during Jun.‐Aug. 1983. During the study, one group had a single resident male while the other group had multiple adult males. Within the multimale group, experienced adult males were no more successful than the subadult male. The sole resident male had a significantly higher rate of fights won (p < 0.02) although he did not differ from the multimale group males in rate of aggression or initiation of fights. We found no significant differences in either mating success or female preference based on males' experience or residency. The rates at which males copulated with and were solicited by females were not significantly correlated. We found no evidence of stable dominance ranks among males in the multimale group and aggressive success was not significantly correlated with copulation rate for males in the multimale group. Subadult males were responsible for the majority of copulations observed during the final third of the breeding season. Our observations of this patas population showed a fluid number of males in groups, with the same groups able to shift rapidly from single to multimale structure. This fluidity may result from the large fluctuations in numbers of breeding‐age males and females observed over 4 yr of studying this population.
Mother — Offspring Conflict in the Saharan Arrui, Ammotragus lervia sahariensis: Relation to Weaning and Mother's Sexual Activity
Authors: Cassinello Jorge
Published: May 2010

Behavioural conflict between mother and offspring was investigated in a captive population of the Saharan arrui (Ammotragus lervia sahariensis, Artiodactyla: Bovidae). The frequency of agonistic behaviours (mother's aggressiveness and calf's retreats) and unsuccessful suckling attempts, Hinde's proximity index and the distances between mother and calf have been analysed in relation to weaning and sexual activity of the mother. Mothers that conceive in the following mating season accelerate the weaning process of their current offspring; furthermore, high‐ranking females wean their male calves earlier. Behavioural conflict occurs during the resumption of the mother's sexual activity; however, no conflict appears to happen during weaning.
Opportunistic Egg Feeding in the Kleptoparasitic Spider Argyrodes gibbosus
Authors: Pasquet Alain , Leborgne Raymond , Cantarella Theresa
Published: May 2010

Argyrodes gibbosus is a kleptoparasitic spider in the web of spiders. It generally steals freshly captured prey from the web of its host. In Sicily, Argyrodes gibbosus parasitizes webs of the spider Cyrtophora citricola, a facultative colonial species.

When a C. citricola female was present in its web, Argyrodes caught small prey in the web or tried to rob prey captured by the host; in that case, we never observed successful attacks on host egg‐sacs. When the host disappeared from its web, the kleptoparasite modified its foraging strategies and attacked the host egg‐sacs and ate the eggs. The exploitation of this new resource could ensure rapid development for the kleptoparasite which was characterized by the presence of larger females and a higher mating rate.
Antipredator Behaviour and Suppressed Aggression by Convict Cichlids in response to Injury‐released Chemical Cues of Conspecifics but not to those of an Allopatric Heterospecific
Authors: Wisenden Brian D. , Sargent R. Craig
Published: May 2010

In aquatic environments, chemical cues serve as an important source of information for the detection of predation risk. Here, we investigate the response of convict cichlids, Cichlasoma nigrofasciatum, to injury‐released chemical cues. We exposed pairs of juvenile convict cichlids first to dechlorinated tap water (control), then later to one of two test stimuli: 1. chemical cues from injured convict cichlids; or 2. chemical cues from injured mosquito fish, Gambusia affinis. Gambusia are allopatric and phylogenetically unrelated to convict cichlids. Gambusia skin was used to control for a general response to injured fish. In response to conspecific cues, convict cichlids significantly increased time spent near the bottom of test aquaria and time under a shelter object. In response to Gambusia skin, convict cichlids tended to increase time spent near the tank bottom but did not increase use of the shelter object. There was a trade‐off between antipredator and agonistic behaviours. In response to convict cichlid cues, there was a significant reduction in the frequency of approaches and bites. Gambusia skin extract had no significant effect on aggressive behaviour. These data suggest a species‐specific antipredator response to conspecific alarm pheromones in a New World cichlid fish and demonstrate a trade‐off between predator avoidance and intraspecific aggression. Further, the presence of an alarm response in this model species sets the stage for the use of chemical cues as a research tool to manipulate predation risk in studies of the interaction between predation risk and reproductive behaviour.
Mate Choice and Reproductive Success in the American Kestrel: a Role for Blood Parasites?
Authors: Wiehn Jürgen , Korpimáki Erkki , Bildstein Keith L. , Sorjonen Jorma
Published: May 2010

Blood parasites of breeding American kestrels,Falco sparverius(40 males and 27 females), were investigated to determine their connections to male showiness, mating success and host fitness. The only haematozoan found in the blood films wasHaemoproteus tinnunculi(overall prevalence of 74% for females and 53% for males). In adult (+ 1‐year‐old) males, the subterminal tail band (character apparently used in female mate choice) was wider in infected males than in non‐infected males. This was consistent with the Hamilton—Zuk hypothesis of parasite‐mediated sexual selection. Our results also suggest that reproductive effort may increase susceptibility to parasitism. In yearling males, the proportion of individuals infected withH. tinnunuliwas higher among those tending a large than a small brood at the time of fledging. Hunting effort (proportion of time spent in flight‐hunting and wind‐hovering) was also higher for males tending large broods than for those tending small broods, and it was higher for yearling than adult males on a given brood size. Reproductive effort may result in greater exposure and/or decreased ability to control chronic latent infections. Parasitic infections, in turn, may have detrimental effects on host fitness.
Prey Detection in Two Tit Species, Parus ater and P. cristatus
Authors: Kothbauer‐Hellmann Renate , Winkler Hans
Published: May 2010

We studied the prey‐detection response of two related tit species (Parus ater, coal tit, and P. cristatus, crested tit) which occur in similar habitats and which are separated by microhabitat use and mode of locomotion. Specifically, we tested whether the two species differ in their ability to detect cryptic prey, with the hypothesis that coal tits perform better because of their longer stays in microhabitat patches. We expected that interspecific differences and the flexible responses within species to different levels of prey crypticity both depend on search intensity. In the experiments, tits had to forage in four different prey conditions: conspicuous + small, conspicuous + large, cryptic + small, and cryptic + large. Capture success, the time needed to detect prey, and stare duration were measured. Both species were less successful with cryptic than with conspicuous prey and did worst with small and cryptic prey. They also needed more time for detection and stared longer when prey was cryptic. When prey had been overlooked, preceding stare durations were shorter than those ending in successful searches. There were clear differences between the species in performance, with the crested tit doing worse. Coal tits, on average, were more successful in detecting prey, returned less frequently to already emptied patches, detected prey faster and yet they stared more briefly. The within‐species results support current notions on predator search, but the differences between species cannot be explained with the same mechanisms. We discuss these findings in the context of the foraging ecology of these species and conclude that crested tits use different cues to detect prey and/or search a larger area per unit time.
Does Male Badge Size Signal Status in Small Island Populations of House Sparrows, Passer domesticus?
Authors: Solberg Erling Johan , Ringsby Thor Harald
Published: May 2010

The relationship between dominance and throat badge size, body size, and body condition was examined in three small island populations of house sparrows, Passer domesticus, on the coast of northern Norway. Individual dominance rank in males was determined by observation of agonistic interactions in an artificial observation cage (one replicate in Dec. and one in Mar. in two populations and one replicate in Mar. in the third population). Previous studies had indicated that badge size signals status in house sparrows. In this study, because of the small population sizes and stability in their membership, we expected that prior information about fighting ability would reduce the importance of badge size for the outcome of conflicts in favour of traits most directly associated with fighting ability. In two of five replicates, significant relationships were found between components of body size and dominance rank, but in opposite directions. The relationship between badge size and dominance rank was consistently positive, but non‐significant. In a pooled sample of the three independent replicates, badge size was the best predictor of dominance, and no other variable explained any variance in dominance. However, the coefficient of determination was low and linearity of dominance hierarchies was poor. We therefore suggest that individual recognition may influence the dominance relationships.
Wing‐flick Signals in the Courtship of the African Cave Cricket, Phaeophilacris spectrum
Authors: Heidelbach J. , Dambach M.
Published: May 2010

The male of the African cave cricket Phaeophilacris spectrum (Saltatoria: Grylloidea: Phalangopsidae) possesses tegmina without stridulatory organs, and both females and males lack tympanal organs. Therefore acoustic communication in the usual sense, which is typical for most crickets, is absent in this species. However, adaptations of the wing articulation allow the males to flick their wings forward over their heads. During courtship these movements are performed in series of 4–5 wing‐flicks at a rate of 8–12 Hz (called wing‐flick series = WFS) which elicit low‐frequency air movements. Such signals may have taken over the functional significance of an acoustic ‘courtship song’. A quantitative analysis of the cricket's behaviour showed that in terms of frequency and total duration, ‘wing‐flick series’ and ‘rocking’ behaviour are the most prominent signals of the male's courtship display. Moreover, analysis of the spatial relationships between male and female demonstrates that the wing‐flicking is directed towards the female. The response of a female to a wing‐flicking, courting male seems mainly to be calmed down and to reach a passive, receptive state, necessary for subsequent copulation. Females confronted with a male's courtship display exhibited a significantly higher threshold to disturbing stimuli than uncourted ones.
Female Mate Preference for Males Having Long and Symmetric Fins in the Bower‐holding Cichlid Cyathopharynx furcifer
Authors: Karino Kenji
Published: May 2010

Female mate preference in a bower‐holding cichlid, Cyathopharynx furcifer, was studied in Lake Tanganyika. Most males held territories with crater‐shaped bowers in sand, but some males held territories without bowers. Territories were distributed adjacently and females visited them to spawn. After engaging in circling behaviour with the male, a female deposited eggs in the bower. Soon after spawning, the female picked the eggs up into her mouth and brooded them in places away from male territories. Female mate choice appeared to follow three steps: 1) females visited only bower‐holding male territories, and more frequently visited territories of males that performed courtship displays at a higher frequency and had longer pelvic fins; 2) females preferred to start circling with males having longer and more symmetrical pelvic fins; 3) females chose males with more symmetrical pelvic fins as their mates. Less than 7% of females that visited male territories spawned eggs in the bowers. In contrast to other bower‐holding species, bower size did not correlate with male reproductive success in C. furcifer. Bowers may therefore be essential as spawning sites or may function as a species recognition character for females. Female choice may be dependent instead on males having long and symmetrical pelvic fins apparent during the circling behaviour carried out in the bowers.
Predator‐induced Swarms in the Tadpoles of an African Savanna Frog, Phrynomantis microps
Authors: Rödel Mark‐Oliver , Linsenmair K. Eduard
Published: May 2010

Aggregations in tadpoles of the West African savanna frog Phrynomantis microps were often observed in their breeding ponds in our study area, situated in Comoé National Park, Ivory Coast. Experiments under seminatural conditions demonstrated that this behaviour was only shown while predators were present. The tadpoles reacted differently to different predators. Factors inducing swarm behaviour were optical (the predator) and/or chemical (liquid from injured tadpoles). Alarm substances are not species‐specific. Kinship seems not to play a role in swarm formation.
Aggressive Mimicry by the Characid Fish Erythrinus erythrinus
Authors: Brosset André
Published: May 2010

The young Erythrinus erythrinus mimics the colour pattern of the female of its specific prey, the cyprinodont fish Rivulus agilae. The male Rivulus is attracted by the predator, and, when performing sexual display in front of it, is caught by the tail and swallowed. Various experiments in captivity confirm the constancy of this behavioural pattern.

The morphological, ecological and behavioural specializations related to the aggressive mimicry by Erythrinus are described. The colour pattern of the young Erythrinus disappears completely when the fish becomes subadult and leaves the highly specialized habitat of the Rivulus, to settle in deeper water. Comparisons between the present case and other described cases of aggressive mimicry are made. The evolutionary processes involved in aggressive mimicry displayed by Erythrinus are examined: origin of the morphological adaptations in the predator, consequences for the population dynamics in the prey.
The Antipredator Vigilance of Adult and Juvenile Thirteen‐lined Ground Squirrels (Sciuridae: Spermophilus tridecemlineatus): Visual Obstruction and Simulated Hawk Attacks
Authors: Arenz Cody L. , Leger Daniel W.
Published: May 2010

Visual antipredator vigilance was predicted to increase in the presence of visual obstructions that do not otherwise provide cover. This hypothesis was tested using 13‐lined ground squirrels as they fed in four Plexiglas boxes that varied in the extent and location of visual obstruction. Adults and juveniles of both sexes were studied. Adults reacted to long‐range lateral visual occlusion and total occlusion by withdrawing more often and assuming both more pronounced and lengthy alert postures relative to short‐range lateral occlusion and no occlusion. Juveniles were less vigilant than adults and did not behave differently in the four treatment conditions. There were no sex differences. Simulated hawk attacks on squirrels feeding in the boxes indicate that the greater vigilance of adults led to significantly reduced reaction times compared with juveniles.
Learning and Task Interference by Corpse‐removal Specialists in Honey Bee Colonies
Authors: Trumbo Stephen T. , Robinson Gene E.
Published: May 2010

Undertakers are considered to be among the most specialized of pre‐foraging honey bee (Apis mellifera L.) workers. In this study we examined a possible benefit and a cost of the corpse‐rem oval specialty, the improvement in performance with experience, and interference by individuals attempting to perform the same task in the same location, respectively. Experienced bees removed corpses significantly faster than less experienced bees and also were less likely to drop corpses while exiting the hive (5.5% vs. 14.3% of attempts). Superior performance by experienced undertakers might occur as a consequence of learning, or by greater ability from the outset. Because active undertakers (≥ 3 corpse removals) did not improve with experience over their own careers, learning was not demonstrated. An extreme specialist, Yellow 54, removed a total of 114 corpses (33.8% of experimentally introduced dead bees) from the hive over a 13‐day period. This is the longest recorded tenure of undertaking to date and demonstrates how a few individuals can dominate this task in a honey bee colony‐Yellow 54 removed corpses significantly faster than other active bees, but she demonstrated no obvious improvement in performance over her undertaking career. This suggests the possibility that active undertakers were more talented than less active undertakers, irrespective of learning. When two undertakers worked together to remove a corpse from the hive, they took longer to complete the task than did single individuals. When multiple undertakers flew together from the hive, they were less likely to clear a nearby obstruction than single undertakers and were more likely to drop the corpse within 1 m of the hive. Thus, mutual interference exacted a measurable cost as a result of the undertaking specialization while learning provided few benefits.
Alarm Calling and Implications for Risk Perception in a Desert Baboon Population
Authors: Cowlishaw Guy
Published: May 2010

Patterns of alarm calling and their implications for perceived predation risk were explored among adult baboons Papio cynocephalus ursinus in four social groups differing in both size and composition (22–55 members with one to six adult males) in a desert population. Data were collected in a field experiment where alarm calls were elicited from baboons under similar conditions of risk in response to the approach of a potential predator, a human observer. The results show that females call more frequently than males in most groups. In addition, the median calling rate of females shows an exponential increase in smaller groups. These patterns suggest that females in small groups may perceive the highest risk in this population. Nevertheless, there was no clear tendency for either sex to be the first to call. The observer approaches were also used to evaluate the influence of group size on the ease of detection of 1. the baboons by the observer; and 2. the observer by the baboons. Group size did not appear to affect detection distances for either subject, although the probability that baboons were more likely to perform alarm calls before the observer had detected them increased in smaller groups.
Social Organization and Foraging Behaviour of the Fishing Bat, Noctilio leporinus (Chiroptera:Noctilionidae)
Authors: Brooke Anne P.
Published: May 2010

Female Noctilio leporinus roost in groups that remain together, associated with the same individuals and in the same location, for several years regardless of turnover in resident males and movements of the group to alternate roosts. Females scent marked themselves with the sub‐axial secretions of other females by rubbing their heads beneath other bats' wings. Males residing with female groups retain their tenure for two or more reproductive seasons. Bachelor males roost solitarily or in small groups apart from females. Together, these characteristics appear to form the basis of a polygynous social organization.

Female N. leporinus foraged solitarily or in small groups with other females from the same roost group. Stable female roost groups forage together and return to the same foraging areas over long periods of time. Bats assembled into small groups outside of the roost and flew together to foraging areas. Females from one roost group were monitored using the same foraging area for over a year. Bats foraged close enough to each other to communicate the location of prey either passively or actively. Roosts were not used as information centres, as bats rarely followed each other from the roost to forage. Males foraged solitarily, utilizing areas that were different from, and larger than, those of the females.
Sponge Carrying by Dolphins (Delphinidae, Tursiops sp.): A Foraging Specialization Involving Tool Use?
Authors: Smolker Rachel , Richards Andrew , Connor Richard , Mann Janet , Berggren Per
Published: May 2010

During long‐term research on bottlenose dolphins (Tursiops sp.) in Shark Bay, Western Australia, several individuals were observed carrying sponges, Echinodictyum mesenterinum, on their rostra. Over multiple years, five regularly sighted individuals were usually carrying sponges when encountered (67–100% of encounters). Four additional regularly sighted individuals were observed with sponges just one time each. All five individuals that routinely carried sponges were female. Two of the anomalous, one‐time carriers were female, one was likely female, and one was male. Most observations of sponge carrying occurred within a restricted area, a relatively deep water channel (8–10 m deep). Surface observations of sponge carrying, including focal animal observations, revealed a stereotyped surfacing and diving pattern, and occasional indications of prey consumption. Three hypotheses are considered regarding the function of sponge carrying: 1. dolphins were playing with the sponges; 2. the sponges contain some compound of use to the dolphins (e.g. for medicinal purposes); and 3. the sponges were used as a tool to aid in foraging. The foraging tool hypothesis is best supported, but the exact manner in which sponges are used remains to be discovered. Sponge carrying is a behavioural specialization, probably involving foraging, and regularly engaged in by only a small proportion of female dolphins in Shark Bay.
Autonomous Learning in Maze Solution by Octopus
Authors: Moriyama Tohru , Gunji Yukio‐Pegio
Published: May 2010

We tested seven octopuses, Octopus vulgaris, in maze‐learning experiments. They tried to reach the goal, so as to get a reward, by using various locomotory actions in the path, and sometimes encountered obstacles. They came to select efficient swimming actions in the path; afterwards less efficient tactile actions (crawling, staying put, and so on: these reduce the speed of movement) gradually increased, while time to detour around the obstacle was reduced. To investigate whether octopuses reduce time spent detouring around obstacles by estimating their actions in the path, we devised a trade‐off situation in which octopuses were obliged to use tactile actions even though the set‐up also encouraged them to use swimming actions. As a result, we could observe that they reduced the detouring time. In that way, we experimentally constituted a perspective as if octopuses looked around the whole maze and estimated their actions. Such a perspective appeared to be autonomous learning.
Diet Overlap and Polyspecific Associations of Red Colobus and Diana Monkeys in the Taï National Park, Ivory Coast
Authors: Wachter Bettina , Schabel Maria , Noë Ronald
Published: May 2010

One possible explanation for the occurrence of the frequent associations between red colobus monkeys and Diana monkeys we observed in Taï National Park, Ivory Coast, is that the two species meet by chance at commonly used food patches. An analysis of the overlap of diets showed, however, that foraging in the same trees could only explain a fraction of the total time in association. Therefore two functional explanations are considered: improvement of foraging efficiency and reduction of mortality due to predation. We did not find any evidence for an improved access to food sources. We conclude that, by default, the predation hypothesis provides the most plausible explanation.
Size‐dependent Mating Behaviours of Male Sand‐bubbler Crab, Scopimera globosa: Alternative Tactics in the Life History
Authors: Koga Tsunenori , Murai Minoru
Published: May 2010

Factors leading to the separation of mating behaviours were investigated in the sand‐bubbler crab, Scopimera globosa. The crabs mated on the surface (surface copulation, SC) and underground (UC). UC males were large (old) whilst SC males were small (young). Burrowless females bred in the UC males' burrows. These females accepted UC in exchange for access to a burrow. UC occurred much more frequently than SC in the burrow area in which females oviposited. Most SC occurred in the water‐saturated area affording a rich diet. SC was accepted by most large and small females in both areas and most UC by small females in the burrow area. SC was an alternative to UC for males in that there was a size dependence between types of copulation. These two mating behaviours involved different degrees of interaction with neighbouring males. Males attempting to carry a female to their burrows for UC were more often disturbed by other males than were males attempting SC. In the interaction for both UC and SC, larger males were likely to resist the disturbances. UC males needed their own burrows, but these burrows were not enlarged before mating. UC males have a higher paternity of eggs than SC males, because SC males' sperm is often displaced by other males. Thus, UC was a behaviour with relatively higher costs and benefits for male crabs than SC behaviour. Alternative mating behaviours in male S. globosa are conditional, and explained by intrasexual interactions and a male life history strategy with a trade‐off between growth and reproduction. It is not likely that the size dependence of male mating behaviour is caused by mate preference of females for UC males in the burrow area.
Sexual Strategies of a North American ‘Tarantula’ (Araneae: Theraphosidae)
Authors: Shillington Cara , Verrell Paul
Published: May 2010

Despite their general notoriety and popularity as pets, little is known of the behavioural ecology of ‘tarantulas’ or theraphosid spiders. We studied a theraphosid of the Arizona deserts,Aphonopelmasp., to determine behavioural events crucial to successful courtship and mating. Males search for spatially scattered females and, at short range, may detect females by substrate‐borne cues. When two males are present with a single female, no direct competition such as aggression is observed. Both males may mate with a single female in rapid succession, with no evidence of post‐copulatory mate guarding. Despite the potential for sexual cannibalism, courtship and mating behaviour patterns exhibit few aggressive elements and males nearly always survive sexual encounters with females. The mating system of thisAphonopelmaspecies may best be described as a type of scramble‐competition polygyny, in which the ability of males to locate receptive females is an important determinant of mating success in males. Multiple mating by females renders predictions concerning fertilization success uncertain, due to the possibility of sperm competition and ‘cryptic’ female mate choice.
Chemical Alarm Signalling in Terrestrial Salamanders: Intra‐ and Interspecific Responses
Authors: Chivers Douglas P. , Kiesecker Joseph M. , Wildy Erica L. , Anderson Michael T. , Blaustein Andrew R.
Published: May 2010

Chemical alarm cues are known to be important in mediating predator avoidance in a variety of taxonomic groups. The purpose of this study was to test whether three species of salamanders that co‐occur in the coastal mountains of Oregon utilize chemical alarm cues in predator avoidance. In laboratory experiments, Western redback salamanders, Plethodon vehiculum, and Southern torrent salamanders, Rhyacotriton variegatus, exhibited an avoidance response to stimuli from injured conspecifics, while Dunn's salamanders, Plethodon dunni did not. Additional experiments demonstrated interspecific alarm responses. P. vehiculum and R. variegatus responded to each other's alarm cues but did not respond to the alarm cues of allotopic long‐toed salamanders, Ambystoma macrodactylum. For R. variegatus, this is despite the fact that they are more closely related to the allotopic species (A. macrodactylum) than to the syntopic species (P. vehiculum). Thus phylogeny alone may not explain patterns of cross‐species alarm responses. Instead, interspecific alarm responses may occur between syntopic species that belong to the same prey guild (i.e. those species that co‐occur spatially and temporally and are exposed to the same suite of predators).
Weaning and Parent‐Offspring Conflict in the Domestic Dog
Authors: Malm Kerstin , Jensen Per
Published: May 2010

Weaning and signs of a parent‐offspring conflict were studied in four females of the Swedish Dachsbracken breed of domestic dog and their pups. The animals were observed from the second to the seventh week of age of the pups. In addition to regular weighing, measurements of milk and solid food intake per pup and meal were also made, and samples of milk from the mothers were collected and analysed. The most important mechanism for weaning seemed to be on the behavioural level. The time that the mother spent with her pups decreased continuously from week 2 to week 7, as did the number of sucklings per hour. Furthermore, both duration of suckling and the number of sucklings initiated by the mother decreased during the period, while the proportion of sucklings where the mother was standing increased steadily. The weights of mothers stayed rather constant during the period and there was no difference in the amount of milk given per suckling or in the composition of milk between the early and late weeks of lactation. Consequently, costs for the mother, in terms of loss of weight, were negligible as she was able to compensate for the increased energy demand of lactation with an increased food intake. There was a tendency for care‐giving behaviour to decrease and aggression from the mother to increase at the same time as there was a tendency for care‐seeking and contact‐seeking behaviour from the pups to increase. These changes, together with the less frequent initiation of suckling by the mother, could perhaps be seen as signs of conflict. Conflict was defined according to TRIVERS' theory (1974) and referred to the disagreement between the female and her pups about the amount of care given. However, although the animals were kept in a way that allowed them to perform as much as possible of their natural behaviour, the good nutritional conditions, one of the characteristics of captive life, may have reduced overt parent‐offspring conflict.
Trophallaxis and Aggression in the Ponerine Ant, Ponera coarctata: Implications for the Evolution of Liquid Food Exchange in the Hymenoptera
Authors: Liebig Jürgen , Heinze Jürgen , Hölldobler Bert
Published: May 2010

Trophallaxis (i.e. the exchange of alimentary liquid among colony members) plays a major role in the societies of many social Hymenoptera. Food is often not equally distributed among nestmates but instead is directed towards more dominant individuals by means of trophallaxis. Antagonistic behaviour can be associated with the exchange of food, or aggression may trigger the offering of food, even where social food exchange does not normally occur.

In orphaned colonies of the ponerine ant,Ponera coarctata, workers interact aggressively at a high frequency. They establish hierarchies soon after the removal of the reproductive queen. One of the consequences of aggression among workers is trophallaxis, which also occurs regularly, although less frequently, in queenright colonies.

The connection of trophallaxis and aggression inPonera coarctataand in many other species of the Hymenoptera is discussed. This study and various other examples show that, besides the nutritional function of trophallaxis, the offering of food may often serve as an appeasement behaviour during aggressive interactions. We speculate that appeasing food offers may have provided the basis for the further evolution and elaboration of trophallaxis in many social Hymenoptera.
Use of Song Amplitude for Ranging in Carolina Wrens, Thryothorus ludovicianus
Authors: Naguib Marc
Published: May 2010

Songbirds are well known to use the degradation of conspecific song to assess the distance of the singer (called ranging). Because a song's degradation accumulates progressively with propagation distance and thus is not under direct control of the singer, it potentially provides more reliable distance information than the amplitude of songs. However, song amplitude decreases progressively with distance and thus also provides information about the singer's distance, provided that interference from wind is low and that the sender does not alter broadcast volume. This study investigated whether or not Carolina wrens, Thryothorus ludovicianus, can use changes in amplitude of conspecific song as a relative cue for ranging. Twelve male subjects each received one playback consisting of two successive songs differing by 6 dB in amplitude. Half the subjects received playbacks with the louder song first and the other half received playbacks with the louder song second. Receivers that would use song amplitude for ranging would perceive the simulated rival either as approaching or retreating, depending on whether the louder song was played first or second. Subjects responded as if the rival was farther away in the simulated retreat than in the simulated approach, indicating that Carolina wrens can use differences in amplitude of successive songs for ranging. Apparently, the risk of inaccurate ranging by song amplitude is outweighed by the advantage of using multiple cues, including information from song amplitude, to assess a rival's distance.