bluuebunny/crossref_metadata_2025_split huggingface dataset:
Song Variation in the Chiffchaffs (Phylloscopus collybita) of the Western Pyrenees — the Contact Zone between the collybita and brehmii Forms
Authors: Salomon Marc , Hemim Younes 
Published: May 2010

AbstractSong variation in west‐Pyrenean chiffchaffs was thoroughly analyzed. Intrinsic physical structures of these songs as well as extrinsic contextual ones were processed simultaneously in qualitative and correspondence analyses. The aim was to assess objectively and to describe the song differences between collybita and brehmii, easily perceived in the field, accounting for variation within the groups due to other sources than taxonomic. All songs originate from the contact zone of the two forms, i.e. taxonomically still‐undetermined entities. The following results were obtained:

The main source of song variation is confirmed to be the bird's membership in the collybita or the brehmii form. Each song type has been characterized in terms of physical variable values.
Within these forms, the songs emitted in the same social or temporal contexts are more similar than the songs produced in different contexts. This has been verified intra‐ and interindividually.
Some individuals have songs that share structures of both forms — these are the mixed‐singers described by Thielcke & Linsenmair (1963).
In the sympatric zone, the acoustic differences between collybita and brehmii are strengthened by an acoustic character displacement.
Sex Change in Both Directions by Alteration of Social Dominance in Trimma okinawae (Pisces: Gobiidae)
Authors: Sunobe Tomoki , Nakazono Akinobu 
Published: May 2010

AbstractThe mating system of the gobiid fish Trimma okinawae is one of polygynous hermaphroditism, in which the largest female of a social unit changes sex following the removal of the dominant male. Histological observations of the gonads however, revealed that males have an ovarian tissue within a functional testis. The occurrence of ovarian tissue in the functional male suggests that T. okinawae males should be able to revert back into being functional females. To test this prediction, we placed females in an aquarium and allowed them to change sex. After confirming sex change from female to male, we individually placed new males into another aquarium and added a larger male to each. Our experiments revealed that females change sex and become males upon the removal of dominant males, and that those males changed sex again and became females in the presence of larger males. Sex change in both directions may be advantageous when a male is forced to become subordinate following the take over of the social unit by a larger male.
Maternal Anxiety in Rhesus Macaques (Macaca mulatta)
Authors: Maestripieri Dario 
Published: May 2010

AbstractVisual monitoring and scratching were used as behavioral indicators of maternal and social anxiety in small captive groups of rhesus macaques. Young infants were especially at risk from other group members during the first weeks of locomotion away from their mothers. Mothers received aggression from other individuals irrespective of their infants' presence or absence. The rate at which mothers scratched themselves increased significantly when their infants moved away from them and when the infants approached or were approached by individuals who frequently harassed them. The rate of maternal scratching and the rate of glancing at the infant and at other individuals when the infant was away decreased as infants grew older and became less vulnerable to harassment. In contrast, the rate of maternal scratching and visual monitoring of other individuals when the infant was in contact remained stable across the first 12 wk of lactation. The rate of maternal scratching increased when the mother‐infant pair was in spatial proximity to the adult male or higher ranking adult females. Although visual monitoring and scratching showed a similar sensitivity to social variables, it is speculated that they might reflect different components of anxiety, namely, anticipation of danger and uncertainty due to motivational conflict. The results of this investigation indicate that a macaque mother's emotional reactivity to a perceived danger for herself and her infant can be measured quite accurately using the rates of visual monitoring and scratching and that the latter represent reliable tools to investigate the emotional correlates of maternal behavior in nonhuman primates.
Size‐assortative Monogamy and Paternal Egg Care in a Coral Goby Paragobiodon echinocephalus
Authors: Kuwamura Tetsuo , Yogo Yutaka , Nakashima Yasuhiro 
Published: May 2010

AbstractParagobiodon echinocephalus (Pisces; Gobiidae) inhabits the branching coral Stylophora pistillata. Only the largest two fish bred in a coral irrespective of group size, which was larger in larger corals. Breeding pairs consisted of a male and female of similar body size. Eggs were spawned on the coral branch and guarded by the male parent for about 4 days until hatching. Successive spawning occurred usually one day after hatching. The reproductive success of a pair, measured as the number of newly hatched larvae, was positively correlated with the body size of the male as well as the female. That is, not only female fecundity but also male ability of egg guarding were limited by body size almost equally. This should promote size‐assortative monogamy in the goby.
The Conflict between Nest Guarding and Mate Guarding in Penduline Tits (Remiz pendulinus)
Authors: Schleicher Brigitte , Valera Francisco , Hoi Herbert 
Published: May 2010

AbstractIn penduline tits (Remiz pendulinus), polygynous males build several very elaborate nests successively during one breeding season to attract females. The time and effort invested in nest building is positively related to their mating success. Intraspecific competition for nest material resulting in nest material theft, delays males' nest building progress which in turn decreases their mating success. Therefore, a nest guarding strategy was predicted. In many bird species, males develop some kind of paternity strategy during the female fertile phase. However, as nest building and the female fertile phase frequently coincide, one would expect a trade‐off between these strategies. In this study we determined in particular how nest guarding in males conflicts with their mate guarding behaviour in penduline tits.Our results show that nest building is costly in terms of a male's time budget. Thieves benefit by increasing their rate of acquiring nest material which reduces the effort invested in nest building. Nest guarding is an efficient strategy to avoid thieves, as indicated by the negative relation between the presence of the male near the nest and the frequency of nest material theft. Nest guarding is required for the whole building period but males, however, increased their mate guarding effort during the peak fertile phase to ensure their paternity. The data suggest that, for the trade‐off “mate guarding versus nest guarding”, paternity insurance seems to be more important.
The Use of Conspecific Chemical Cues for Cannibal Avoidance in California Newts(Taricha torosa)
Authors: Elliott Sean A. , Kats Lee B. , Breeding Jennifer A. 
Published: May 2010

AbstractAdult California newts,Taricha torosa(Caudata: Salamandridae), prey on both conspecific egg masses and larvae. We used both laboratory and field experiments to determine if newt larvae use conspecific chemical cues to avoid adult intraspecific predators. Larvae showed significant hiding responses when exposed to adult cues in both the field and the laboratory. Larvae did not exhibit significant hiding responses to chemical cues from invertebrate predators.
Aversive Responses of Female Mice to the Odors of Parasitized Males: Neuromodulatory Mechanisms and Implications for Mate Choice
Authors: Kavaliers Martin , Colwell Douglas D. 
Published: May 2010

AbstractThe detection and avoidance of parasitized conspecifics is proposed to have important consequences for the behavior of animals, especially as related to mate choice. A reduction in pain sensitivity (i.e. analgesia) is a major correlate of exposure to real or potential danger and threatening stimuli, facilitating the expression of various active (e.g. fleeing) and passive (e.g. immobilization) defense responses. The present study examined pain sensitivity (latency of a foot‐lifting response to 50 ° C thermal surface) of female mice,Mus musculus, that were exposed to the urine and other odor secretions of male mice subclinically infected with the naturally occurring, enteric, sporozoan parasite,Eimeria vermiformis.A 30‐min exposure to the odors of a parasitized male induced an analgesia in the female mice that was found to be mediated by the increased activity of endogenous opioid peptide systems. A brief 1‐min exposure to the male odors induced a shorter duration and lower amplitude analgesia of a non‐opioid (serotonergic) nature. Maximum analgesic responses were induced by the odors of pre‐infective [5 days post‐infection (PI)] and infective (day 10 PI) males, with significantly lower responses elicited by the odors of post‐infective (day 17 PI) male mice. Exposure to the odors of unparasitized males had no significant effects on the pain sensitivity of female mice. These results indicate that female mice can distinguish between the odors of parasitized and non‐parasitized male mice, and find the odors of parasitized males threatening and/or stressful. These odor‐induced analgesic responses and their neurohormonal correlates may be part of an adaptive preparatory defense mechanism that facilitates the detection and avoidance of parasitized males by female mice and contributes to female mate choice.
The Social Organization of Feral Ovis aries Ram Groups in the Pre‐rut Period
Authors: Rowell T. E. , Rowell C. A. 
Published: May 2010

AbstractPrimates are described as having peculiarly complex social behaviour when compared with other mammals, but the methods and expectations of primatologists also differ from those of other mammalogists, confounding the comparison. A very simple social organization has been described for sheep (Ovis aries). Rams of a long‐established feral flock were observed during the pre‐rut period of three successive years, and their communicative behaviour was described and quantified using individual‐focussed methods commonly applied to primates. Rams were found to form long term relationships and their pattern of interaction was partly determined by these as well as by age and rank. Correlation between the effects of age and rank varied with current demography. There was no correlation between rank and horn size. Rams intervened on behalf of weaker colleagues and supported each other in fights. They showed more affiliative behaviour and associated more closely than did ewes. While the leader of the ewe flock was nearly always the oldest ewe present, leadership of ram flocks was less restricted; when together, rams always followed the ewe flock. Comparison is drawn between monkey and sheep social behaviour, and it is concluded that perceived differences are partly due to differences in the expectations and methods of their respective students.
Comparison of the Hunting Behavior of Four Piscine Predators Attacking Schooling Prey
Authors: Parrish Julia K. 
Published: May 2010

AbstractFour piscine predator species were observed repeatedly attacking large (> 100,000) schools of flat‐iron herring, Harengula thrissina. The predators could be categorized into two groups. Stalking predators (two species) were slow‐moving, predominantly solitary hunters attacking from positions beneath the school. Attacks were directed at individual prey and the sequence of events was orient‐approach‐strike. Although the stalking species were seen most often and were responsible for the majority of the attacks, capture success was low. The remaining two species were fast‐moving, pelagic hunters regularly occurring in groups of up to 8 individuals. These predators were extremely proficient at capturing prey, either by orienting on individuals (stragglers) or accelerating into the school and ramming their prey (impact attacks). Group size was positively associated with capture success, but not significantly so. Because stalking predators orient towards individual prey, they may suffer from the effect of confusion when attacking schooling prey. Use of the impact strategy, by comparison, may allow predators to overcome the confusion effect either by attacking prey already separated from the school, or by orienting towards aggregated prey rather than particular individuals.
Landmark Territoriality in the Neotropical Paper Wasps Polistes canadensis (L.) and P. carnifex (F.) (Hymenoptera: Vespidae)
Authors: Polak Michal 
Published: May 2010

AbstractMale Polistes canadensis and P. carnifex aggregate along crests of prominent ridges in Santa Rosa National Park, Costa Rica. At these sites males of both species defend territories (trees and shrubs) by chasing conspecific rivals. Territories do not contain nests or resources that are collected by females. Chasing by territorial males reduces the amount of time spent by intruders in a territory. I describe and contrast male territorial behavior of both species. Some male P. canadensis are territorial while others in the same area exhibit patrolling behavior, flying from one occupied territory to another. Males of P. carnifex exhibit territoriality only. Patrolling in P. canadensis is an outcome of relatively high male density along the ridge, rendering territories in short supply, as shown by the observation that experimentally vacated territories are seized rapidly by formerly patrolling males. Due to a high intraspecific intrusion rate, territorial male P. canadensis spend less time perching and more time flying and chasing intruders from their territories than do male P. carnifex. Males of these two species also differ in the placement of their territories along the ridgeline; P. canadensis occupy territories in saddles while P. carnifex occupy those at peaktops. I show that this divergent spatial pattern is not maintained by competitive exclusion of either species by the other, and I discuss alternative explanations for their separate spatial distributions. Comparative data suggest that males are territorial because females restrict matings to within territories, and I discuss alternative hypotheses to explain this bias in female behavior.
Laughter Punctuates Speech: Linguistic, Social and Gender Contexts of Laughter
Authors: Provine Robert R. 
Published: May 2010

AbstractThe relation between laughter and speech was investigated by describing the position of naturally occurring laughter in the speech stream of anonymous young adults observed in public places. Laughter of both speaker and audience occurred during pauses at the end of phrases or sentences in over 99 % of the sample of 1200 episodes of laughter, indicating that speech has priority access to the single vocalization channel and that a lawful process governs the placement of laughter in speech. Laughter is not randomly scattered throughout the speech stream. Laughter followed both statements and questions and material that did not seem humorous outside of the conversational context. Speakers, especially females, laughed more than their audiences, but the relative amount of speaker and audience laughter depended on the gender composition of a group. Audiences of both males and females laughed more to male than female speakers. These baseline data provide insights into gender differences, normal and abnormal emotional behavior and define variables for future studies of neuro‐and psychopathology.
Information and Patch Exploitation Strategies of the Eastern Chipmunk, Tamias striatus (Rodentia: Sciuridae)
Authors: Bowers Michael A. , Adams‐Manson Robert H. 
Published: May 2010

AbstractWe examined to what extent 15 chipmunks foraging from dishes in the field varied load sizes depending on a predetermined sequence of resource renewal/removal. At 10‐m distances from burrows, chipmunks collected smaller loads when seeds were replenished over sequential trials and larger load sizes when trials were interrupted by removing all seeds for one visit. Similar sequence effects were less obvious at 0 m. Load size also varied with travel time but not in a manner consistent with either long‐term rate maximization or resource tracking. When travel time effects were removed, sequence effects became more pronounced at distances of both 0 and 10 m. The results suggest that chipmunks use past experience in patches to gauge expected returns in the future, and that they devalue resources according to their uncertainty (“future discounting”). That chipmunks varied load sizes with food renewal/removal more at 10 than 0 m from burrows suggests that the degree to which chipmunks devalue future resources may depend on how defendable those resources are.
The Mating Strategy of the Male Short‐tailed Cricket Anurogryllus muticus de Geer
Authors: Lee How‐Jing , Loher Werner 
Published: May 2010

AbstractMales of Anurogryllus muticus de Geer call with a sound intensity of 92–95 dB SPL/20 cm. The nightly calling time is 198 ± 79.5 min. Singing begins with the onset of darkness, and is under circadian control (τLL = 25.35 h). At 27 ° C, O2‐consumption during rest is 1.7 ml/h/g, whereas for calling O2‐consumption rises to 10.76 ml/h/g. According to the CO2/O2 ratio, A. muticus burns carbohydrates and lipids at rest, but mostly lipids during stridulation (R = 0.8). The type of fuel oxidized is rapidly adjusted to the particular behavior expressed. The testes serve as a reservoir for lipids, and their lipid level rises from 33.2 ± 15.4 μg/mg tissue at the imaginal molt to 95.2 ± 43.1 μg/mg tissue by the age of 30 days, although by that time testis size has shrunk by 90 %. Multiple, brief matings compensate for short calling times due to high energy expenditure. Comparative data for Teleogryllus oceanicus and T. commodus are given, where appropriate.
Delayed Plumage Maturation and Orderly Queues for Status: A Manakin Mannequin Experiment
Authors: McDonald David B. 
Published: May 2010

AbstractLek‐mating male long‐tailed manakins (Chiroxiphia linearis) move through three distinct, unambiguously age‐specific, predefinitive (subadult) plumages, and do not attain the definitive (“adult”) male plumage until their fourth year. Males form orderly, generally age‐graded queues for rank in leks. The top‐ranking (alpha and beta) males cooperate in courtship display, although only alphas copulate. Taxidermic model experiments tested the function of the 3‐yr delay in plumage maturation. Reaction to a model manakin in female‐like, first‐year predefinitive plumage was stronger than that to a treatment control or a neutral species but weaker than that to a model manakin in definitive plumage. Reaction to the model manakins resembled mobbing choruses directed at model snakes, indicating that the reaction was a response to a potential threat. The results did not support female mimicry, juvenile mimicry, molt constraints or predator crypticity hypotheses for delayed plumage maturation. Decisive rejection of the first two hypotheses would require further experiments with model females and models of the other predefinitive stages. Nevertheless, none of the four hypotheses is sufficient to explain age‐specific plumage stages. The results were, however, consistent with a status‐signaling hypothesis that suffices to explain successive age‐specific plumages. The reaction to models was often by non‐alpha males, who had no opportunity for copulations. The presence of the models, therefore, appeared to pose a threat to the system of male‐male alliances rather than a risk of stolen copulations. By choosing with high discrimination among leks (queues), females appear to enforce orderly male queuing. The predifinitive plumages, therefore, seem to function as age‐specific badges of status that indicate a male is a queue entrant. The plumages mediate but do not eliminate aggression during the several years of becoming established in lek assemblages.
Song Perception in the Song Sparrow: Importance of Different Parts of the Song in Song Type Classification
Authors: Horning Cynthia L. , Beecher Michael D. , Stoddard Philip K. , Campbell S. Elizabeth 
Published: May 2010

AbstractSong sparrow (Melospiza melodia) males have repertoires of 6 to 12 song types, each song consisting of four or five contrasting phrases. Song types vary both within individuals (a singer varies successive renditions of a type within a singing bout) and between individuals (neighbors sing slightly different versions of a type), and in both cases this variation is concentrated in the later parts of the song. We speculated that type variation in the later parts of the song might be correlated with a perceptual tendency to classify song types primarily on the basis of the earlier parts of the song. We tested this hypothesis using a laboratory conditioning technique, supplemented by a field playback experiment. In the lab, song sparrows and white crowned sparrows were trained to discriminate between two distinct song types. In test sessions, they were presented with hybrid songs synthesized from varying proportions of the two training song types. For most birds and most song pairs, song classification was influenced by all parts of the song, with the beginning elements being most important. The field playback experiment used song type matching as the response measure. Each subject was presented a hybrid stimulus song consisting of the first half of one of his song types and the second half of another of his song types. Subjects replied with both ‘front matches’ and ‘back matches’ (60% were front matches).
Can Paradise Fish (Macropodus opercularis, Anabantidae) Recognize a Natural Predator? An Ethological Analysis
Authors: Gerlai Robert 
Published: May 2010

AbstractPredator recognition and avoidance by paradise fish have been studied with allopatric species and model experiments. The effect of sympatric predators has not been investigated. Here I report that reactions of paradise fish towards a sympatric predator (Channa micropeltes) are quantitatively different from those shown towards an allopatric predator or different harmless species of fishes. I investigate the possible cues eliciting this differential response and show that visual as well as olfactory stimuli play roles. Olfactory stimuli from the sympatric predator alone elicit an elevated level of activity from paradise fish; the appearance of the sympatric predator (with or without olfactory stimuli) results in an exploratory and display reaction. I speculate what visual stimuli may play roles in predator recognition in paradise fish and I suggest that previously asserted key stimuli such as the eyes of the encountered heterospecific fish may not differentiate the harmful species from innocuous. I conclude that the antipredatory behavior of paradise fish may be affected by both genetic factors and learning and that the relative importance of the former or latter factor may vary depending on the situation.