bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reversed Sexual Size Dimorphism and Parental Care: Minimal Division of Labour in the Blue-Footed Booby
Authors: Guerra Maria , Drummond Hugh 
Published: April 2008

Abstract
Reversed sexual size dimorphism in avian species (females larger than males) may be an adaptive consequence of different roles of males and females in parental care. We examined the alleged division of labour in two-chick broods of the blue-footed booby, using behavioural observation and frequent weighing of chicks. In the first week of parental care, males and females fed broods at similar frequencies and provided similar masses of food, but females brooded more than males when broods were 5-10 d old. Subsequently, females provided a greater mass of food and frequency of feeds than males until chicks were at least 35 d old (mass) and 60 d old (frequency), while attending the brood for just as much time as males until chicks were at least 35 d old. Males and females did not differ in the tendency to feed (frequency and mass) the first-hatched chick differentially. In nearly all components of parental care examined here, and in other studies, the female's contribution is equal to or greater than the male's. Only in clutch attendance and nest defence does the male contribute more than the female, but his small size seems unlikely to enhance performance in these activities. Overall, small size appears potentially to limit male provisioning of the brood, and is unlikely to be an adaptation for division oflabour in parental care. This result casts doubt on the relevance of the division-of-labour hypothesis for adult size dimorphism.
Mating Strategy and Reproductive Success in the Teiid Lizard, Ameiva Plei
Authors: Censky Ellen J. 
Published: April 2008

AbstractCurrent selection on sexual size dimorphism was studied in a widely foraging non-territorial lizard, Ameiva plei. Males were significantly larger than females. Large males won intrasexual agonistic encounters and guarded females during their entire receptive period (1-4 days). Guarding males spent significantly less time foraging than males who were alone. Only males that guarded females were observed to mate. Mating success was highly skewed with only six of 21 mature males in the study site observed mating. All six males who mated were 141 mm SVL (males mature at 62 mm SVL). The four largest males obtained 84% of all observed matings and were estimated to have fertilized 88% of the eggs. Sexual selection appears to favor large size in males due to competition among males to guard females. Large females on Anguilla also had higher reproductive success bccause SVL was positively correlated with clutch size and number of clutches in a season. It appears that natural selection has favored different trade-offs between growth and reproduction in males and females.
How Do Hens View Other Hens? the Use of Lateral and Binocular Visual Fields in Social Recognition
Authors: Dawkins Marian Stamp 
Published: April 2008

AbstractWhen shown familiar and unfamiliar birds at different distances, hens viewed birds 0.7 m or 1.4 m away with modal head angles between 54° and 72° from the midline, using the lateral visual field but viewed birds closer (less than 20 cm) binocularly, with the head within 18° either side of the midline (Expt. 1 When faced with a choice between a familiar and an unfamiliar bird at different distances, hens chose the familiar bird if the choice could be made 8 cm away but their choices were random if they had to chose 66 or 124 cm away (Expt. 2). This suggests that hens may be unable to discriminate familiar from unfamiliar birds except when they are very close to them. Observations of freely moving birds suddenly confronted with another hen (Expt. 3) showed that even when the object bird was familiar, it was in all cases initially scrutinized from a close distance (26 cm or less), which is consistent with the hypothesis that hens are unable to recognize other birds except when close enough to view them with the myopic lower frontal field. Reasons for this constraint on social recognition are discussed.
UNDERSTANDING THE EVOLUTION OF BEHAVIOR IN THREESPINE STICKLEBACK: THE VALUE OF GEOGRAPHIC VARIATION
Authors: Foster Susan A. 
Published: April 2008

AbstractThe endemic radiation of the threespine stickleback in North America possesses features that will permit us to gain unique insights into evolutionary pattern and process. Already, comparison of populations has demonstrated a remarkable level of adaptive differentiation in reproductive behavior across populations in both southern British Columbia, Canada, and the Cook Inlet Region of Alaska, U.S.A. In small, shallow lakes, threespine stickleback feed predominantly on benthic invertebrates in the shallow littoral zone. They form large groups that attack nests defended by males, and consume all of the young within. In contrast, in larger, more oligotrophic lakes, adult stickleback feed primarily on plankton in large open-water foraging groups. They do not form groups that cannibalize young in nests. In these non-cannibalistic populations, males perform more conspicuous courtship behavior than do those in cannibalistic populations, apparently because risk of attack by visually hunting conspecifics is low. Courtship in these lakes more often includes the conspicuous zig-zag dance, and less often, meandering and dorsal pricking. Anadromous populations tend to be cannibalistic, but also are often behaviorally intermediate. They incorporate the zig-zag dance in courtship more often than do males in cannibalistic freshwater populations, but also usually incorporate the less conspicuous dorsal pricking behavior. These results suggest that the ancestral condition was intermediate and that both cannibalistic and non-cannibalistic freshwater populations display some derived elements in their reproductive repertoires. This kind of comparison among populations thought to have been independently derived from the marine form can provide insights into the patterns and causes of adaptive diversification. For populations such as these, carefully chosen from disparate geographic locations so as to preclude common evolutionary history after colonization of freshwater,
Foraging Behaviour and Memory Window in Sticklebacks
Authors: Mackney P.A. , Hughes R.N. 
Published: April 2008

Abstract
Individuals were collected from a residential marine population of Spinachia spinachia, an anadromous population of Gasterosteus aculeatus forma trachura and a residential freshwater population of G. aculeatus forma leiura. After maintenance for 2 months on a diet of mysid, individuals were subjected to ten, consecutive daily trials on a diet of amphipods or oligochaetes. During this period, individuals learned to handle the prey more effectively, as measured by attack efficiency, handling efficiency and handling time. Learning was similar among populations but differed between diets, being more pronounced for amphipods, which are more difficult to catch and handle than oligochaetes. Once trained to these diets, fish were tested for foraging efficiency after successively longer periods of stimulus deprivation, when they were fed a maintenance diet of mysid. All three measures of foraging efficiency with the amphipod diet, but only that based on handling time with the oligochacte diet, declined to naive levels in the residential marine and anadromous populations. No decrease in foraging efficiency with either diet occurred in the residential freshwater population. Memory window was 8 d, 10 d and > 25 d in the residential marine, anadromous and residential freshwater populations respectively. The large difference between the freshwater and two marine populations is interpreted as an adaptive response to the stability of arrays of prey, characteristic of their respective habitats.
Response of Male European Starlings To Experimental Removal of Their Mate During Different Stages of the Breeding Cycle
Authors: Pinxten Rianne , Eens Marcel , Verheyen Rudolf Frans 
Published: April 2008

Abstract
We experimentally removed females from monogamous European starling Sturnus vulgaris pairs during different stages of the breeding cycle and recorded the effect of these removals on male behaviour and on offspring survival in order to assess the possibilities for female mate desertion. Removal of the female during the laying, incubation and early nestling stage (1- to 5-day-old nestlings) invariably resulted in complete failure of the brood. The survival of the nestlings improved slightly if the female was removed during the middle nestling stage (6- to 10-day-old nestlings), but mortality rate of nestlings was still significantly higher than in control two-parent broods. About 80% of the males widowed during the laying/incubation period removed all eggs from the nest, while only 49% of all males widowed during the early and middle nestling stage removed all dead nestlings. Removal of eggs/dead nestlings by a widowed male starling probably functions to increase the chance on a successful re-mating, since replacement clutches were found only in nests whereof the clutch/brood was removed. We recorded one definite and at least nine suspected cases of parental infanticide, the killing of own offspring, by experimentally widowed male starlings. After nestlings reached 10 days of age (late nestling stage), there was no longer a significant difference in nestling mortality rate between male-only and two-parent broods. This crucial point coincides with the time when (1) the nestlings are functionally homeothermic, and (2) the exponential growth of the nestlings begins to moderate. Moreover, at this time, late in the season, the only viable option for deserted males is to care for the young because the probability of renesting successfully is low. Our results thus indicate that after nestlings reach 10 days of age, female starlings may have the opportunity to desert their mate. However, at that time, the benefits of female mate desertion are reduced as opportunities for renesting succesfully are low.
How Much Does Social Group Size Influence Golden Marmot Vigilance?
Authors: Blumstein Daniel T. 
Published: April 2008

AbstractA commonly cited benefit of group living is the ability for individuals to reduce the time devoted to scanning for predators with increasing group size - the 'group size effect'. Interestingly, most studies reporting a group size effect have focused on documenting a significant group size effect and did not discuss the relative 'importance' of group size. One way to study the relative importance of group size is to calculate the amount of variation in vigilance explained by group size. I studied effects of social group size on golden marmot (Marmota caudata aurea) vigilance in two ways. First, I estimated the overall amount of time marmots were vigilant during their morning active periods. Second, I estimated the amount of time marmots were vigilant specifically while foraging. Analyses statistically controlled for several factors that have been suggested to confound the study of group size effects. While marmots were active, only 14% of the variation in vigilance was explained by social group size. For foraging marmots, even less variation (about 6%) was explained by social group size. The amount of variation explained by social group size in golden marmots is considerably less that reported in several studies of other species where explained variation was reported or could be estimated from data. Some of the discrepancy between variation explained in this and other studies may stem from my focus on social group size which appears to explain less variation than the more commonly studied foraging aggregation size. However, species differ in the amount of time they devote to foraging and therefore vary in the magnitude of net benefit from group size effects. Future comparative work will be required to rigorously study the relationship between amount of time foraging and the magnitude of group size effects.
Anti-Predator Responses To Conspecific and Heterospecific Skin Extracts By Threespine Sticklebacks: Alarm Pheromones Revisited
Authors: Brown Grant E. , Godin JEAN-GUY J. 
Published: April 2008

AbstractUnder laboratory conditions, we investigated the presence of chemical alarm signals in the threespine stickleback (Gasterosteus aculeatus). We exposed individual threespine sticklebacks to skin extract of conspecifics originating from either the same or a different population, fourspine sticklebacks (Apeltes quadracus; a member of the same prey guild as the threespine stickleback) or swordtails (Xiphophorus helleri), a species not known to possess alarm pheromones and which is phylogenetically distant and allopatric from the threespine stickleback. Threespine sticklebacks exhibited significant increases in anti-predator behaviour patterns when presented with skin extract from both populations of conspecifics and from fourspine sticklebacks, but not to swordtail skin extract. These results suggest, contrary to previous reports, that threespine sticklebacks possess chemical alarm signals, which appear to be similar to those of Ostariophysan fishes.
Reproductive Behaviour of Sea Trout (Salmo Trutta) - the Consequences of Sea-Ranching
Authors: Petersson Erik , Järvi Torbjorn 
Published: April 2008

Abstract
Reproductive behaviour and factors associated with male and female mating success were studied in sea trout (Salmo trutta) in a stream water aquarium, during three successive years. We compared a sea-ranched and a wild-produced strain, both of the same genetic origin. In general, dominant males courted females more often, spent more time on the spawnable areas, and had higher mating success than lower ranked males. Body mass explained about 18% of the males' position in the dominance hierarchy. Sea-ranched males, however, achieved on average fewer matings than wild ones. Wild males courted the nest-preparing females and chased away other males more frequently than did the sea-ranched males. Females were observed to be aggressive towards males, especially when the females were preparing a nest. The males that were more frequently the target of female aggression had smaller adipose fins and were more often aggressive towards females. In general the females spawned just once in each nest. Sea-ranched females defended and tested their redd less frequently than the wild females did. Digging activity by wild females diminished closer to spawning time, but not that of the sea-ranched females. To what extent the observed differences were due to the environmental conditions or to genetic differences is not known at present. However, the results of previous studies have revealed that behavioural and morphological differences exist between the strains, despite being reared under the same conditions. Thus, the behavioural changes noted in the sea-ranched sea-trout might have a genetic element.
A Comparative Study of Aggression and Conciliation in Three Cercopithecine Monkeys (Macaca Fuscata, Macaca Nigra, Papio Papio)
Authors: Petit O. , Abegg C. , Thierry B. 
Published: April 2008

AbstractPatterns of aggression and reconciliation were studied in three captive groups of monkeys belonging to different species: Japanese macaques (Macaca fuscata), crested macaques (M. nigra) and Guinea baboons (Papio papio). Consistent differences were found comparing same dyads of individuals in the three groups. Aggression was often followed by retaliation and reconciliation in the group of crested macaques, such responses occurred less frequently in the group of Japanese macaques, more variable results were found in the group of Guinea baboons. Aggressive manual contacts occurred more frequently in crested macaques than in the other two groups. Rates of biting did not differ consistently among groups but bites could induce bleeding in the group of Japanese macaques. The use of peaceful interventions in conflicts was common in crested macaques, rare in Guinea baboons and unobserved in Japanese macaques. Data from other studies indicate that the contrasts found between groups could be due to interspecific variation. The present results suggest that the covariation between conciliation rates, degree of symmetry in conflicts and level of intensity in aggression may stem from phylogenetic constraints.
Twin/Non-Twin Discrimination By Lambs: an Investigation of Salient Stimulus Characteristics
Authors: Porter Richard H. , Nowak Raymond , Orgeur Pierre , Lévy Frédéric , Schaal Benoist 
Published: April 2008

Abstract
A series of experiments was conducted to elucidate the stimuli that mediate twin/non-twin discrimination among 2-3 week old lambs. After being separated from their mother, lambs emitted more distress bleats when tested in isolation than when penned with their familiar twin, but separated from that lamb by a barrier of evenly spaced wood bars. A similar, albeit weaker effect was found for paired vs isolated non-twins. Twins separated by the barrier bleated less than did the non-twins in this condition. In contrast, bleat rates did not differ when subject lambs were tested in the presence of their twin vs a non-twin on the opposite side of a solid opaque barrier. Intact lambs in a final experiment bleated less when tested with their tranquillized twin vs a tranquillized non-twin agemate. The tranquillized stimulus lambs displayed atypical behavior patterns, including suppression of bleats and reduced activity levels. These data indicate that full bodily contact, vocalizations or normal behavioral patterns are not necessary for lambs to be recognized by their twin. Rather, twin/non-twin discrimination (and the effect of a twin on the rate of distress bleating) appears to depend upon visual, and possibly olfactory cues.
Response of the Tadpole Shrimp Triops Longica Udatus To Hypoxia
Authors: Scholnick David A. , Snyder Gregory K. 
Published: April 2008

AbstractTadpole shrimp, Triops loregicaudatus live at the bottom of small ephemeral pools where the supply of oxygen is extremely variable. When oxygen tensions in the lower water layers are low, shrimp make numerous trips to the surface in order to obtain oxygen to satisfy metabolic demand. These trips to the surface are disruptive to the normal growth and development of the shrimp because they are energetically costly and they require time away from the benthic feeding zone. This study investigated the negative impact of time spent at the surface on growth and the extent to which hemolymph hemoglobin concentration, [Hb], increase the capacity of animals to remain submerged in hypoxic waters. Hemolymph [Hb] were found to be inversely related to the oxygen tension in which animals were raised and positively correlated with the amount of time spent in the benthic feeding zone during hypoxia. Individuals that spent more time in the benthic feeding zone had higher growth rates than those which spent more time at the surface during hypoxia. We conclude that extracellular [Hb] is an important adaptation in T. longicaudatus by facilitating oxygen uptake during hypoxia, allowing animals to spend more time in benthic habitats where they feed thereby increasing growth and possibly reproductive success.
On a New Genus and New Species of Potamid Crab (Brachyura) From Burma
Authors: Ng Peter K.L. 
Published: April 2008

AbstractA new genus and new species of potamid freshwater crab from Burma (present Myanmar), Flabellamon pretzmanni, is described. Flabellamon differs from other potamid genera in having a flat, transverse carapace with well developed epibranchial teeth which are separated from the external orbital angles by deep V-shaped clefts, and a short and relatively stout G1 which has a well developed fold on the dorsal margin of the terminal segment. The taxonomic status of two supposedly allied species, Potamon turgidulum Alcock, 1909, and Potamon kuehnelti Pretzmann, 1963, is also discussed.
A Brief History of Existential - Phenomenological Psychiatry a n d pSychotherapy
Authors: Halling Steen , Dearborn Nill Judy 
Published: April 2008

AbstractThis article provides a historical overview of the Existential-Phenomenological tradition in psychiatry and psychotherapy, tracing its development from its origin in nineteenth and twentieth century philosophical thought, through its major European psychiatric proponents and schools, to its emergence as an influential approach in North America after World War II. The emphasis is on the implicit themes that provide continuity within this movement as well as on the distinctive contributions of individual thinkers. We conclude with a discussion of the present status and future prospects of this tradition.
Zur Konzeption Der Islamischen Stadt
Authors: Wirth Eugen 
Published: April 2008

AbstractVorbemerkung: Mit Rücksicht auf nicht-orientalistische Leser wurde bei allen Fach-termini (z.B. sŪq, bān, rawda) auf eine korrekte arabische Pluralbildung verzichtet. Die Schreibweise arabischer Eigennamen folgt den üblichen Regeln. Ausnahmen davon erschienen überall dort geboten, wo bei allgemeiner bekannten Termini eine eingedeutschte Form zur Verfügung stand (z.B. Kairo, Damaskus, Aleppo, Teheran). Soweit es bei den Ortsnamen keine solchen Formen gibt, richtet sich die Schreibweise nach den Internationalen Kartenwerken 1:1 Mio. und 1:500.000. Deren Transkription ist für Nordafrika meist französisch, für Vorderasien meist englisch. Bei Zitaten und Literaturtiteln wurde selbstverständlich die von den jeweiligen Autoren gewählte Schreibweise beibehalten. Für wertvolle Hinweise und Anregungen ist der Verf. zahlreichen Fachkollegen verschiedenster Disziplinen zu herzlichem Dank verbunden. Genannt seien hier insbesondere die Damen Frau M. Barrucand (Paris) und Frau B. Finster (Bamberg) sowie die Herren K. Deller (Heidelberg), R. Endres (Erlangen), B. Fragner (Bamberg), H. Ganslandt (Erlangen), W. Hütteroth (Erlangen), D. Huff (Teheran/Berlin), B. Johansen (Berlin), K. Kreiser (Bamberg), W. Müller-Wiener (Darmstadt), H. Nissen (Berlin), J.-P. Pascual (Aix-en-Provence), G. Wirth (Bonn) und R. Zippelius (Erlangen). Der Deutschen Forschungsgemeinschaft und der Stiftung Volkswagenwerk sei auch an dieser Stelle für die stete treue Unterstützung vieler Reisen in den Orient aufrichtig gedankt. Ohne deren Hilfe wären die seit 1964 laufenden ausgedehnten Feldforschungen der Erlanger Geographen zu Fragen der orientalischen Stadt nicht möglich gewesen.
Individual, collective and group rights: History, theory, practice and contemporary evolution
Authors: Ramcharan B.G. 
Published: April 2008

AbstractThis paper discusses the contemporary debate about collective and group rights in the light of actual cases, relevant literature, and emerging international norms. It offers the following submissions: 1. Group rights or collective rights are not incompatible with the intellectual history of human rights. 2. States are at liberty to work out arrangements that recognize rights for groups within the State or for members of the group. 3. The list of group or collective rights explicitly recognized by contemporary international law is still a rather short one. It has so far dealt mainly with the right of self-determination, the rights of minorities and of indigenous populations. 4. Recent statements on the rights of minorities contain explicit affirmations of their right to: existence, identity, participation, to establish associations, to establish and maintain contacts, to culture, to profess and practice their religion, to use their language, to establish schools and to protection. 5. Any recognition of group or collective rights should be complementary to, and not restrictive of, the rights contained in the Universal Declaration and the International Covenants. 6. The international community is competent to scrutinize the way in which claims to group or collective rights are dealt with nationally. 7. The international community should provide avenues, recourse procedures and specialized fora for promoting international cooperation on issues of group and collective rights. 8. It would seem a worthwhile policy objective for a global study to be made about claims and needs for the recognition of group rights.