bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parental Care and Polygyny in the Chiffchaff Phylloscopus Collybita
Authors: Rodrigues Marcos 
Published: April 2008

AbstractThe males of most bird species help to raise the young, and females may suffer costs from polygyny because of having to share the male parental care. In the chiffchaff (Phylloscopus collybita) nests of monogamously and polygynously mated females had similar success in relation to the proportion of fledged young. Overall, male chiffchaffs provided little assistance to females during the nestling period, but they increased help when the young left the nest. Females who choose already-paired males (secondary females) incurred lower reproductive success, because they were unable to start a second brood after raising their first brood. Primary and monogamous females which received male help in the form of food provisioning during the fledgling period were more likely to attempt a second brood. This is the first study that reports associated costs to secondary females due to the lack of paternal aid after the young have fledged the nest. However, secondary females still can obtain compensatory benefits, as predicted by the polygyny threshold model, since most of them settled in good quality habitats, close to the primary females.
The Influence of Siblings On Wild Infant Chimpanzee Social Interaction
Authors: Brent L. , Bramblett C.A. , Bard K.A. , Bloomsmith M.A. , Blangero J. 
Published: April 2008

Abstract
The presence or absence of older siblings influenced the social interactions of 17 wild infant chimpanzees between the ages of 6 and 24 months living at the Gombe National Park, Tanzania. The total amount of time spent in social interaction (contact, grooming and play) was similar for infants with and without siblings, as was the overall level of social interaction with the mother. However, subjects with siblings spent more time with their siblings, while subjects with no siblings interacted with other group members. These results indicate a possible set-point for infant chimpanzee social interaction. Developmental changes were also similar in both groups, but the infants with siblings had lower levels of interaction with the mother and higher levels of interaction with other group members during the age period of 12-18 months. The levels of social behaviors were not related to the sex of the infant.
Ontogeny of Diving Behaviour in the Galápagos Fur Seal
Authors: Horning Markus , Trillmich Fritz 
Published: April 2008

AbstractWe studied the ontogeny of diving behaviour in the Galápagos fur seal (Arctocephalus galapagoensis, Heller 1904). Six-month-old seals spent less than 12% of observation time at sea and were entirely dependent on maternal milk for nutrition. Maximum dive depths for this age group averaged 5.6 m, maximum durations 50 s (N = 12). Modal swim speeds averaged 0.55 m/s; maximum observed swim speeds ranged from 0.9-2 m/s (N = 5). Six-month-old seals swam distances of 2.9 km/24 hrs on average (N = 5). No diel patterns were apparent in their diving behaviour. One-year-old fur seals were the youngest age group to show substantial diving activity, reaching maximum depths of 47.5 m and durations of 2.4 min on average (N = 21). Modal swim speeds averaged 0.9 m/s, maximum speeds ranged from 1.4-2.3 m/s (N = 6). Total distances traveled averaged 15.4 km/trip to sea. Yearlings spent 23.9% of observation time at sea, the majority (> 95%) of that at night. This corresponds to the activity pattern of adult females who dive exclusively at night. Yearlings were the youngest age group to contribute to their own nutrition through independent foraging, but were still dependent on their mothers: no yearlings were successfully weaned in this study. 18-month-old seals were better divers, spending 27.6% of observation time at sea, mostly during the night. Maximum dive depths for this age group averaged 61.1 m; durations 3.1 min (N = 11). Modal swim speeds averaged 1.4 m/s (N = 4), and were comparable to modal speeds of two adult females of 1.2 and 1.6 m/s. Maximum speeds for these juveniles ranged from 2.2-2.7 m/s (N = 4); the two adult females reached 2.8 and 4 m/s respectively. Total travel distances averaged 42 km/trip to sea (N = 4 juveniles). These distances corresponded to those covered by two adult females, 43 and 45 km/trip. Two-year-old fur seals included the youngest that were successfully weaned in this study. They spent 35% of observation time at sea, primarily at night. Maximum dive depths averaged 69.7 m, durations 3.4 min (N = 20). Adult females were the best divers in this study, spending 49.5% of observation time at sea, almost exclusively at night. Maximum dive depths averaged 106.5 m, durations 4.5 min (N = 32). During ontogeny, age was the best predictor of time spent at sea. For animals older than six months, body mass was the best predictor for maximum dive depth as well as maximum and median durations. The physiological maturation process precludes weaning before the age of one year. After that, the diving capacity of young fur seals takes a central role in the weaning process, in conjunction with the temporal patterns of relative prey accessibility.
An Experimental Study of Cache Recovery By Hoarding Willow Tits After Different Retention Intervals
Authors: Brodin Anders , Kunz Camilla 
Published: April 2008

Abstract
We allowed seven willow tits, Parus montanus, to store and retrieve with retention intervals of 1, 7, 21 and 56 days, in four experimental rooms. Retrieval success decreased over time, indicating a decaying memory for cache locations. Compared to what could be expected by chance, retrieval success was better after all retention intervals. Our results suggest that - after the longer retention intervals - this might depend on preferences for certain types of caching locations rather than memory. If both general and individual preferences are controlled for, birds retrieved significantly better than expected one and seven days after storing, but not later than that.
Song Rate Correlates With Paternal Care and Survival in Willow Tits: Advertisement of Male Quality?
Authors: Welling P. Petteri , Rytkonen Seppo O. , Koivula Kari T. , Orell Markku I. 
Published: April 2008

Abstract
Dawn song in birds may advertise male quality in terms of parental care and/or survival. Males who sing most may also be the best parents, and eager singing may also reflect good chances of a male's or his mate's survival. These relationships were studied in the willow tit Parus montanus, a species with a simple and relatively non-variant song. Song output was expressed as the proportion of time a male spent singing at dawn. Later in the breeding season, two aspects of parental care, nest defence and feeding effort, were measured in the same males. High song output was associated with more intense nest defence behaviour (eager singers attacked the predator model more often and approached closer to it) and high nestling feeding effort. However, reproductive success was not associated with song output, although males with high song rates tended to be more likely to produce recruits. Males who survived to the next year had higher song intensity than males who did not survive, while female survival was not correlated with song output of her mate. The results suggest that dawn song in the willow tit advertises male quality. Some aspects of honest advertisement and female choice are discussed.
Song Tutoring Influences Female Song Preferences in Domesticated Canaries
Authors: Nagle Laurent , Kreutzer Michel L. 
Published: April 2008

Abstract
Laboratory experiments were designed to examine the influence of previous acoustic experience on later song preferences in female domesticated canaries (Serinus canaria). Young females were reared in acoustic isolation (five groups). In these five groups, one was reared without tutoring and four were exposed to taped tutoring songs (playbacks of three different songs, two conspecific and one heterospecific). One of the four tutored groups was exposed to all three songs, while each of the remaining groups was exposed to one of the three songs. When adult, all females were tested using copulation solicitation displays as an index of their song preferences. We demonstrated that females reared without tutoring were especially responsive to a particular domesticated canary song. This song contained a special song phrase type (Vallet & Kreutzer, 1995) that elicits high levels of sexual response. In general, a similar preference was also observed in the groups reared with tutoring. In addition, the females' preferences in tutored groups were also positively and strongly affected by conspecific songs, when these songs had been heard during the previous tutoring. In fact, females seemed to be able to selectively respond to a song containing a special song phrase, but were also able to learn conspecific songs.
Effects of Pair Bond and Presence of Conspecifics On Singing in Captive Zebra Finches
Authors: Dunn Andrew M. , Zann Richard A. 
Published: April 2008

Abstract
Undirected Song is commonly performed in wild and captive zebra finches and is typically given by males partly isolated from other members of the flock or colony. It has no territorial function nor it is used during precoital courtship; its frequency varies strongly among individuals. However, its rate of performance is severely limited by the close proximity of conspecifics, and this study investigated what social factors are responsible for this constraint in first-generation offspring of wild-caught zebra finches. The close presence of females caused a greater reduction in singing than did that of males. Familiarity between companions and the singer was also a factor that reduced the rate of singing. The more familiar the singer became with a female the more often he would sing in her presence, whereas the opposite occurred with males - singing was more prevalent with strangers than with familiar companions. Pair formation reduced a singer's sensitivity to inhibitory factors associated with the close proximity of conspecifics. Simple visual and auditory contact with a conspecific was not sufficient to constrain Undirected Singing, but intense, close range interactions appear to be necessary. It is hypothesised that Undirected Singing is used to attract females for pair formation or extra-pair mating, but the close proximity of male companions and/or the mate hampers this. However, in a competitive mate choice experiment there was no significant correlation between the rate at which a male gave Undirected Song and order of the pair formation. This suggests that Undirected Singing may not be crucial in the ultimate choice of a mate, but it may still be a useful cue at the outset of pair formation.
Female Choice of Males in Cuttlefish (Mollusca: Cephalopoda)
Authors: Geary Boal Jean 
Published: April 2008

AbstractIn captivity, male cuttlefish use visual displays to establish size-based dominance hierarchies and larger males obtain most of the copulations. This experiment was performed to determine if females prefer the larger, more dominant males and whether females use male visual displays to evaluate males. Twenty sexually mature, virgin female cuttlefish were given up to six opportunities to approach one of two males out of a pool of ten adult males, or to approach neither. Females did have significant preferences between males, but they were not related to male dominance. Females showed a consistent and significant preference for the more recently mated male. These preferred males were also more likely to mate again, when given the opportunity, than were less-preferred, less-recently mated males. Females also preferred males that showed fewer zebra displays. Viewing male-male interactions did not affect their choices. Results suggest that female preference could be based on chemical cues, while visual displays may function primarily as agonistic signals. Females who mated did so repeatedly before laying eggs, providing opportunity for sperm competition.
The Interpretation of Animal Psychology: Anthropomorphism or Behavior Reading?
Authors: Mitchell Robert W. , Hamm Mark 
Published: April 2008

Abstract
A perennial problem in the study of behavior has been the basis for anthropomorphic psychological terminology. Research has suggested that people use a nonhuman animal's perceived similarity to humans based on physical likeness, familiarity, phylogeny, and/or cultural stereotype to characterize it psychologically. One further hypothesis is that people use an animal's behavior-in-context to determine its psychological characterization. These diverse hypotheses were evaluated by providing undergraduates with narratives depicting mammalian (including human) behavior suggestive of jealousy or deception, and asking them to evaluate their degree of agreement or disagreement with particular psychological characterizations of the animal described. Narratives varied the species, the context in which a mammal's behavior occurred, and how strongly it was emphasized that the narrative was about a nonhuman (or human) organism. Species varied in their physical similarity, phylogenetic closeness or familiarity to humans, and/or cultural stereotype as human-like; behavior remained constant in all narratives. In general, variations in the context in which behavior occurred influenced psychological characterization, but variations in species and emphasis did not: psychological characterizations of all species were almost always similar. Nonscientists (and some scientists as well) apparently use a mammal's behavior-in-context (whether human or not) as evidence of its psychological nature, regardless of the mammal's physical similarity, familiarity, or phylogenetic closeness to humans, or the mammal's cultural stereotype; psychological terms are not used specifically for humans, but rather are depictive of behavior-in-context. Psychological terms set the stage for further investigation into an organism's psychological abilities; calling such terms 'anthropomorphic' inaccurately implies that they are extrapolated from human behavior, when they appear to be applicable to particular behavior-in-context, independent of the species behaving.
Female Activity Profile of a Polygynous Lizard (Anolis Carolinensis): Evidence of Intersexual Asymmetry
Authors: Nunez Steven C. , Jenssen Thomas A. , Ersland Kasey 
Published: April 2008

Abstract1. The activity profile of free-ranging individuals should reflect how females and males are optimizing their respective reproductive efforts. By using the polygynous, sexually dimorphic lizard, Anolis carolinensis, we expected to find an example of pronounced intersexual asymmetry in daily activity patterns. 2. In contrast to males who should focus on blocking consexual access to resident females, we expected females to strategically facilitate egg production by minimizing conspicuous and unnecessary behavior, while feeding frequently from a defended food resource optimal to their needs. 3. During a 56 day period, we made a 90 h record of focal animal observations on 22 unmanipulated, reproductive females; then we compared this activity profile to a known profile for males. We found the following. 4. Females were 1.6 times more stationary (82% of day), moved 1/7th the distance (< 40 m/day), displayed at 1/8th the overall rate (< 14 displays/h), and used < 1/35th the number of displays in non-directed advertisement (1.6 displays/h) as males. 5. Females spent 1/30th the time (0.3% of day) in overt defense of territories 1/9th the volume (8 m3) as males. 6. However, both females and males had equivalent feeding rates (1.2 times/h), suggesting that the energetic needs of female egg production and male territorial maintenance are comparable. 7. The small, lightly defended territories and low feeding rates of females (along with their reptilian metabolism and insectivorous diet) indicate that females have a wide latitude in which to meet their energetic costs. 8. As expected, the proportion of intersexual contacts was similar between female and male profiles. Courtship and copulations occupied 3.2% and 3.9% of the females' day, respectively, with copula averaging 26 min in duration. 9. In a female activity profile which de-emphasized conspicuousness, we found little evidence for a pheromone-based alternative to visual signalling. 10. Predation, as an immediate threat to lizard activities, was not seen during three months of observations. We noted only four instances of avoidance behavior.
Male-Female Social Relationships in Wild White-Faced Capuchins (Cebus Capucinus)
Authors: Perry Susan 
Published: April 2008

AbstractThis paper describes male-female dyadic social relationships in C. capucinus, detailing the types of costs and benefits exchanged between the sexes. A single group of wild white-faced capuchin monkeys (Cebus capucinus) was studied in Lomas Barbudal Biological Reserve, Costa Rica, for 24 months. A total of 953 hours of focal animal data were collected on 4 adult males and 6 adult females. The patterning of social interactions was studied in an attempt to assess the outcome of disputes between males and females. In dyadic interactions, females avoided and cowered to males roughly 50 times more often than males avoided or cowered to females. Females responded fearfully to 12% of males' neutral approaches, whereas males never responded fearfully to females' neutral approaches. Males supplanted
Mate Choice and Aerobic Capacity in Red Junglefowl
Authors: Chappell Mark A. , Zuk Marlene , Johnsen Torgeir S. , Kwan Timothy H. 
Published: April 2008

Abstract
In 'good genes' models of sexual selection, females choose mates whose genes confer increased survival value to offspring. One possible index of male quality is aerobic capacity (the metabolic basis of sustainable exercise), which is likely to be important for fitness. If it is both heritable and ecologically valuable, high aerobic capacity would be a direct signal of male genetic quality. If aerobic capacity is phenotypically plastic but dependent on health, it may provide an indirect index of male quality in other heritable traits (e.g. pathogen resistance). We examined the relationship between courtship behaviour, aerobic capacity (measured as maximum rates of oxygen consumption), and mating success in red junglefowl (Gallus gallus). We also tested the effects of intestinal parasites (the nematode Ascaridia galli) and plasma testosterone levels on aerobic capacity and behaviour. We found no relationship between testosterone and behaviour, mating success, or aerobic capacity. A. galli infection changed the relationship between mass and aerobic capacity; infected males had lower aerobic capacity than uninfected males, but only for small males. Discriminant function analysis suggested that aerobic capacity and display behaviour, together with male ornaments (comb size and colour), were the most important factors determining the mating success of males. However, aerobic capacity and display rate were not strongly correlated, and the manner by which females can discriminate among males with differing aerobic capacity is unclear.
Does Reproductive Synchrony Limit Male Opportunities or Enhance Female Choice for Extra-Pair Paternity?
Authors: Kempenaers Bart 
Published: April 2008

AbstractBreeding synchrony has been suggested as one factor that might explain the variation in frequency of extra-pair paternity, both between and within species. Reproductive synchrony might limit the opportunities for males to engage in extra-pair copulations (EPCs), because males face a trade-off with guarding their own fertile partner. Alternatively, breeding synchrony may promote extra-pair paternity, because of reduced male-male competition for EPCs or because of enhanced possibilities for females to assess male quality. In this study, I investigated the influence of synchrony on the occurrence of extra-pair paternity in the blue tit Parus caeruleus. Over four years, breeding synchrony and extra-pair paternity were positively related. Within a season, extra-pair paternity occurred independently of the timing of breeding. The fertile period of the extra-pair male's social mate and that of the extra-pair female often overlapped considerably. However, males who performed EPCs during the fertile period of their social mate were not more likely to lose paternity than males who performed EPCs after the fertile period of their mate. These data suggest that breeding synchrony has little influence on the occurrence of extra-pair paternity in the blue tit.
Metastenasellus Powelli Sp. N., a New Stenasellid Isopod Crustacean From Littoral Groundwaters of Southeastern Nigeria
Authors: Magniez Guy 
Published: April 2008

AbstractContrairement à tous les autres Sténasellides, qui vivent dans les eaux souterraines continentales (grottes, nappes phréatiques, sources thermales), la nouvelle espèce a été trouvée dans la zone oligohaline du littoral, près de Port Harcourt, Nigéria. Description de Metastenasellus powelli sp. n. affinités de cette nouvelle espèce, aire géographique et diagnose rénovée du genre Metastenasellus Magniez, 1966, liste des espèces connues à ce jour.
Range Extension of Paguristes Perspicax Nobili, 1906 (Decapoda, Diogenidae) Into the Northern Arabian Sea
Authors: Tirmizi Nasima M. , Siddiqui Feroz Akhtar 
Published: April 2008

Abstract
Paguristes perspicax wird erstmals aus dem nördlichen Arabisch See (bei Karachi) gemeldet und ausführlich beschrieben. Die Variationsbreite wird diskutiert.
Comparative Fecundity of Four Species of Crayfish in Southwestern Ontario, Canada (Decapoda, Astacidea)
Authors: Corey Susan 
Published: April 2008

AbstractLa fécondité de quatre espèces d'écrevisses a été étudiée: Cambarus robustus, Orconectes propinquus, Orconectes rusticus et Orconectes airilis. Les taux de fécondité ont été respectivement pour chaque espèce: C. robustus de 25 à 128, moyenne 64,9; O. propinquus de 26 à 195, moyenne 68,5; O. rusticus de 75 à 351, moyenne 161,8; O. virilis de 29 à 195, moyenne 139,1. La dimension (diamètre) des oeufs est constante dans une même espèce, mais présente d'une espèce à l'autre les variations suivantes: 3,69, 4,55, 6,88 et 40,03 mm3 chez O. propinquus, O. virilis, O. rusticus et C. robustus respectivement. Les pentes de régression de la fécondité en fonction de la taille varient également d'une espèce à une autre; les rapports entre le volume total des oeufs et la surface ventrale de l'abdomen sont similaires, et ceci montre que la fécondité est déterminée à la fois par la taille des oeufs et la surface ventrale de l'abdomen. Les résultats présentés ici sont comparés aux données antérieures de la littérature et quelques aspects écologiques sont discutés.
Morphologie Des Soies Des Appendices Buccaux Et Des Pattes D'Un Mysidacé Cavernicole
Authors: Crouau Y. 
Published: April 2008

AbstractThe mouth-parths and the thoracic appendages of the cavernicolous Mysidacea Antromysis juberthiei were studied by means of scanning electron microscopy to reveal the distribution and the fine morphology of their setae; twelve types of setae are reported; they are compared to antennary setae of the same animal previously studied and to setae of other Crustacea.