bluuebunny/crossref_metadata_2025 huggingface dataset:
The nature and implications of differential predation between Gammarus pulex and G. duebeni celticus (Crustacea: Amphipoda)
Authors: Dick JaimieT. A.
Published: March 2009

The mutual predatory behaviour between Gammarus pulex (Linnaeus, 1758) and Gammarus duebeni celticus (Stock & Pinkster, 1970) is described. The implications of the predatory nature of these species are discussed in terms of the feeding ecology of Gammarus and other amphipods. Predation rates by males on moulted congeneric females are assessed and compared. When males are present at the moult of a congeneric female, 100%of females are eaten in both species/sex combinations. When females are allowed to recover from moulting prior to presentation to a congeneric male, predation rates are significantly reduced in both species. However, significantly more G. d. celticus females are eaten by G. pulex males compared with the reciprocal situation. The predatory ‘clumping’ behaviour of both species is described and shown to be a form of feeding frenzy upon congenerics. Clumping behaviour also results in significantly higher rates of congeneric predation on G. d. celticus females than on G. pulex females. Support is thus given to the hypothesis that differential predation by males on moulted females may be the primary mechanism by which the introduced G. pulex has displaced the native Irish species G. d. celticus. The implications of amphipod congeneric predation are discussed in terms of observed patterns of interspecific coexistence and exclusion.
Quantitative pulmonary anatomy of a ground‐dwelling bird, the white‐breasted water‐hen (Amaurornis phoenicurus)
Authors: King A. S. , Vidyadaran M. K. , Kassim H.
Published: March 2009

Stereological data on the lungs of ground‐dwelling birds are restricted to a few, mainly galliform, species. Data are presented for the non‐galliform, white‐breasted water‐hen. The volume densities of the main parts of the lung and exchange tissue and the surface areas and thicknesses of the components of the blood‐gas pathway were estimated by point counting. The anatomical diffusing capacities of the pathway were then estimated. The main parameters determining gas exchange were normalized with body mass and compared with those of other avian species. The anatomical diffusing capacity of the water‐hen was inferior to that of passerine and trochilid species, similar to that of non‐passerine species reliant on continuous powered flight (mallard) or soaring and gliding (gull), superior to that of domestic galliform species, and strongly superior to that of the flightless emu. It is concluded that selection pressures evolve a lung with a capacity for gas exchange sufficient for the energetic requirements of a particular strategy.
Diving pattern and performance in relation to foraging ecology in the gentoo penguin, Pygoscelis papua
Authors: Williams T. D. , Briggs D. R. , Croxall J. P. , Naito Y. , Kato A.
Published: March 2009

We present data on diving pattern and performance (dive depth, duration, frequency and organization during the foraging trip) in gentoo penguins Pygoscelis papua, obtained using time‐depth recorders (n= 9 birds, 99 foraging trips). These data are used to estimate various parameters of foraging activity, e.g. foraging range, prey capture rates, and are compared in relation to breeding chronology. Foraging trip duration was 6 h and 10 h, and trip frequency 1.0/day and 0.96/day, during the brooding and creche periods, respectively. Birds spent on average 52%of each foraging trip diving. Dive depth and duration were highly bimodal: shallow dives (< 21 m) averaged 4 m and 0.23 min, and deep dives (> 30 m) 80 m and 2.5 min, respectively. Birds spent on average 71%and 25%of total diving time in deep and shallow dives, respectively. For deep dives, dive duration exceeded the subsequent surface interval, but shallow dives were followed by surface intervals 2–3 times dive duration. We suggest that most shallow dives are searching/exploratory dives and most deep dives are feeding dives. Deep dives showed clear diel patterns averaging 40 m at dawn and dusk and 80–90 m at midday. Estimated foraging ranges were 2.3 km and 4.1 km during the brood and creche period, respectively. Foraging trip duration increased by 4 h between the brood and creche periods but total time spent in deep dives (i.e. time spent feeding) was the same (3 h). Of 99 foraging trips, 56%consisted of only one dive bout and 44%of 2–4 bouts delimited by extended surface intervals > 10 min. We suggest that this pattern of diving activity reflects variation in spatial distribution of prey rather than the effect of physiological constraints on diving ability.
Pup weight and survival of northern fur seals Callorhinus ursinus
Authors: Baker J. D. , Fowler C. W.
Published: March 2009

The relationship between northern fur seal pup weight and post‐weaning survival is examined. Males that survived at least two years after weaning had been significantly heavier than the mean for their cohort as pups. Among a small sample of females no significant relationship was found. Cohort survival from weaning to age two was not significantly correlated with mean pup weight. Pup weight may influence post‐weaning survival less than other factors such as gender and variability of the environment. To the degree that it determines survival, pup weight may reflect the reproductive success or fitness of parents. Weight differences between tagged and untagged pups explain, in part, differences observed in their survival.
Age‐related changes in ovarian morphology of the South American tamarin Saguinus fuscicollis (Callitrichidae)
Authors: Mansdotter Stefanie , Epple Gisela , Küderling Irmgard
Published: March 2009

The aim of this histological study was to investigate the postnatal ontogeny of the ovaries in Saguinus fuscicollis to provide a detailed knowledge of the ovarian morphology for further endocrinological studies. Gonads from 43 animals between one day and 18 years of age were investigated. Based on the available material the ovarian development is characterized by seven distinct stages. 1. Neonatal stage: Folliculogenesis is still in progress. The ovarian medulla is filled with an intraovarian rete system, which forms open connections between the rete tubules and the cords containing oocytes. 2. Infantile stage: One month after birth the ovarian cortex is mainly composed of primordial follicles and a few primary follicles at the corticomedullary border, which are separated from each other by connective tissue. At two months, folliculogenesis is nearly completed. The first secondary follicles are present. 3. Juvenile stage: In six‐month‐old females weighing 184±9.5 g, folliculogenesis has reached the stage of secondary follicles with up to six layers of granulosa cells. In females of the same age weighing 251.5±37 g, antral follicles attain a maximum diameter of 925 μmm. 4. Pubertal stage: At the age of 8–10 months, corpora lutea accessoria (CLA) begin to form from atretic antral follicles. 5. Adult stage: The ovaries of all females older than 1.2 years are filled with large patches of interstitial gland tissue (IGT). In breeding females up to 58.4%of the antral follicles are intact. In non‐breeding daughters living in the family group only 1.8%are intact, the rest are in various stages of atresia and form CLA. 6. Climacterial stage: With increasing age (8–13 years), the number of intact follicles decreases dramatically and IGT fills nearly the whole ovary. 7. Senile stage: In females older than 14 years, nearly all remaining follicles show signs of atresia.
Social behaviour and heart rate in tammar wallabies (Macropodidae: Macropus eugenii)
Authors: W. Dressen  , Hendrichs H.
Published: March 2009

In an enclosed group of tammar wallabies the behaviour of all individuals and the heart rate (HR) of three males were recorded simultaneously. The social structure was characterized by the dominance relationships between the males and the sexual preference of all males for the oldest female. During non‐oestrus, dominance was obvious when a male intervened terminating the sexual behaviour of a subdominant one. The relatively low amount of agonistic behaviour between the males is assumed to be due to the clear dominance relationships. Locomotion as well as sexual and agonistic behaviour were accompanied by an acceleration of HR. The HR pattern depended on the intensity of the behaviour, its duration and the animal's identity. Commonly performed sexual behaviour and approach/retreat encounters gave rise to HR values not different from HR values during locomotor activity without interactive components. Social events that occurred infrequently—like fights, and the mating of an oestrous female—were accompanied by strong accelerations of HR indicating high cardiac effort. The mild cardiac activity during common social encounters is consistent with a strategy of maximizing energy conservation. HR patterns during specific behaviour could not entirely be accounted for by the energetic costs of activity. Spreading the forelimbs in response to specific stimuli—like the fly‐over of raptors—was indicative of a strong HR response even if the animal was motionless. During specific social encounters like the sexual behaviour of the alpha‐male following an intervention—HR responses revealed that arousal might exceed motor activity in affecting HR. Individual differences of these HR responses are attributed to the age, experience and social status of a male.
Interspecific variation in daily energy expenditure during avian incubation
Authors: Tatner P. , Bryant D. M.
Published: March 2009

Daily energy expenditure (DEE) of free‐living birds during the incubation and subsequent brood‐rearing stages was measured using the doubly‐labelled water technique for seven species of bird. These data are combined with published information to provide a data set of 17 species of bird covering the mass range 12–85 g.

Allometric relationships between DEE and body mass for the two stages of breeding were constructed using three models (log‐transformation regression, geometric mean regression, and iterative non‐linear regression). The geometric mean regression model was rejected as inappropriate. The iterative non‐linear regression model provides the best predictions of DEE given the average body mass of a species, but is of less value for comparing data sets. The most commonly used model (log transformation regression) was thus favoured for comparative purposes as the predictions it generates do not significantly alter the conclusions that would be obtained with use of the iterative non‐linear regression models (Marquardt model) for the data sets in this work. Comparison between the average DEE for the two stages of breeding suggest higher DEE during the brood‐rearing period, although this was significant in only five species.

The difference in body mass among species can account for more of the variation in average DEE during incubation (r2= 82·6%) than during brood‐rearing (r2= 67·3%1), indicating that other effects such as activity are probably more important determinants of energy expenditure during brood‐rearing.

The residual variation in DEE during incubation, after the effect of body mass had been removed, was considered for groups of species occupying different ecological niches. It is shown that the level of activity and ambient temperature can explain much of the residual variation in DEE during incubation.

The blue tit was used as an example to demonstrate the role of energy balance as a constraint on reproductive success during the incubation period.
The effect of supplementary feeding upon the sizes of the home ranges of woodmice Apodemus sylvaticus living on a system of maritime sand‐dunes
Authors: Akbar Zubaid , Gorman M. L.
Published: March 2009

The woodmouse is primarily a woodland species but it also occurs on maritime sand‐dunes. The home ranges of mice living on the sand‐dunes are much larger than those of animals living in woodlands. Here we test the hypothesis that this difference is due to the fact that woodland provides substantially more food than do sand‐dunes. Our experimental approach was to provide supplementary food in the form of wheatgrain to a sand‐dune population and to compare range sizes with a control population. Range sizes on the supplemented area were significantly smaller than the controls and essentially similar to those of woodmice living in deciduous woodland.
Food of the serotine bat, Eptesicus serotinus—is faecal analysis a valid qualitative and quantitative technique?
Authors: Robinson M. F. , Stebbings R. E.
Published: March 2009

The diet of Epfesicus serotinus was investigated by faecal analysis and the validity of this technique as a means of obtaining reliable quantitative results was assessed. Knowledge of what the bats eat will allow predictions of which habitats contribute most prey. Three male serotines were kept in captivity during the months of July and August 1991 and fed known quantities of identified insects. With captive E. serotinus the remains of prey appeared within 33 min of first bite and continued to appear for up to 32 h after consumption. Scales from two Noctua pronuba moths consumed were contained in 59 subsequent droppings. Similarly, fragments of three beetles, Geotrupes stercorarius, were contained in 28 subsequent faeces.

Analysis of the faeces of free‐living bats revealed insects from seven orders. Coleoptera were found to be present in 96.1% of the droppings examined; the next most frequently found order was Lepidoptera, occurring in 14.7%. The beetles were mostly associated with hay meadows (Aphodius spp. and Melolontha spp.), or grazed pasture (Aphodius spp. and Geotrupes spp.). Quantitative determination of prey eaten is not possible owing to the large number of the droppings shown to contain the remains of marker insects and the long period over which they are produced.
Genital dimorphism in natural populations of the land snail Chondrina clienta and the influence of the environment on its expression
Authors: Baur B. , Chen X. , Baur A.
Published: March 2009

Several species of simultaneously hermaphroditic land snails show a genital dimorphism: aphallic individuals differ from euphallic ones by a lack of male copulatory organs (penis plus genital retractor muscle). Aphallic individuals can self‐fertilize or outcross as females but not as males. Thus, the mating system of a population may be significantly influenced by the proportion of aphallic individuals.

We present data on the frequency of aphally in 23 natural populations of the rock‐dwelling land snail Chondrina clienta on the Baltic island of Öland, Sweden. The populations varied greatly in percentage of aphallic individuals, ranging from 52.2 to 99.1%, (grand mean 77.7%)). This variation did not follow any geographical pattern.

In a laboratory experiment, we examined whether food supply (high or low) and/or population density (high or low) experienced during ontogeny affected the expression of genital dimorphism. Snails derived from a population with 99.1% aphallic individuals and raised under different food and density conditions did not differ from the original population in frequency of aphally. By contrast, when snails from a population with 66.7% aphallic individuals were raised on a low food supply, more individuals became euphallic than expected under complete genetic determination. These results suggest that, in addition to a genetic component. the expression of the genital dimorphism can be influenced by environmental conditions.
The effect of pH on feeding behaviour in newt larvae (Triturus: Amphibia)
Authors: Griffiths R. A.
Published: March 2009

The feeding responses of three species of newt larvae were compared under circumneutral and sublethal acid conditions. Under acid conditions (pH 4.5) feeding behaviour was suppressed in palmate newts, Triturus helveticus, and smooth newts. T. vulgaris, but not in crested newts, T. cristatus. At low pH, approach and orientation towards food occurred in T. helveticus and T. vulgaris, but snapping was inhibited; T. cristatus snapped and consumed food immediately it was offered under the same conditions. These differences are not consistent with the apparent greater tolerance of T helveticus for acidified ponds. The observations suggest that the chemosensory system of T. helveticus and T. vulgaris may be impaired at low pH.
Sex differences in the nursing relationship between mothers and pups in the Atlantic harbour seal, Phoca vitulina concolor
Authors: Rosen D. A. S. , Renouf D.
Published: March 2009

Sex differences in the dynamics of the relationship between harbour seal mothers and their pups were investigated. An index of pair proximity governance suggested that pups became increasingly responsible for maintaining the distance between the pair over the course of the nursing period. Male pups demonstrated a stronger tendency to control initiation distance than female pups. A Nursing Index utilizing suckling bout initiations and terminations revealed that, as weaning approached, pups became progressively more responsible for the continuance of nursing. Male pups exhibited more control than female pups, primarily through initiating a greater portion of the bouts. On‐teat times averaged 4.08 min per bout, with no significant differences between male and female pups. Male pups, however. nursed a greater portion of haul‐out time due to higher bout frequencies obtained through more bout initiations. Mothers did not preferentially reject attempts to nurse by pups of either sex. These results suggest that the tenet of parental investment theory suggesting male pups enjoy preferential investment may be misleading. In harbour seals. male pups seem actively to seek out resources, as opposed to any inherent strategy on the par1 of the mother.
Body mass in large extant and extinct carnivores
Authors: Anyonge William
Published: March 2009

Body mass in six species of Plio‐Pleistocene carnivores was estimated based on the relationship between mass and cross‐sectional geometric properties, distal articular surface area, lengths and circumferences of proximal limb bones (femur and humerus) in 28 species of extant carnivores. All measures, except lengths, were found to give congruent body mass estimates. Two of the extinct carnivores (Smilodon fatalis and Panthera atrox) are estimated to be as much as one and a half times heavier than previously thought. Based on these results inferences are made concerning possible prey species.
The adaptive significance of brood size and time of breeding in the dipper Cinclus cinclus (Aves: Passeriformes) as seen from post‐fledging survival
Authors: Ormerod S. J. , Tyler Stephanie J.
Published: March 2009

We assessed the post‐fledging survival of dippers Cinclus cinclus from 743 broods in relation to brood size, time of hatching and territory quality. We paid particular attention to assessing whether contrasting breeding performance along unproductive (i.e. acidic) and productive (i.e. circumneutral) rivers represented strategies which optimized the number of surviving young.

For all brood sizes, post‐fledging survival varied significantly through the breeding season, with most survivors coming from attempts in the peak period of hatching. After correcting for these seasonal effects, the most common brood size overall, of four, was also the most productive as seen from post‐fledging survival; differences in the frequency of occurrence and survival between broods of four and five were marginal. Moreover, a change in the modal brood size from five to four occurred as the season progressed. consistent with a shift in brood productivity.

Broods at acidic sites were significantly smaller than at circumneutral sites; while brood size four was the most productive at both types of site, brood size three was the second most productive at acidic sites, while brood size five was the second most productive at circumneutral sites. Dippers at acidic sites bred significantly later than at circumneutral sites, but post‐fledging survival declined most rapidly through the season at the former.

These survival data provide evidence from both seasonal and spatial patterns that brood sizes in the dipper may be optimized in ways consistent with the enhancement of productivity. By contrast, delayed breeding at acidic sites contrasted with the patterns expected from optimization, instead reflecting resource scarcity.
Developmental aspects of sleep apnoea in northern elephant seals, Mirounga angustirostris
Authors: Blackwell Susanna B. , Boeuf B. J. Le
Published: March 2009

Northern elephant seals, Miroungu angustirostris, breathe irregularly while sleeping on land, alternating bouts of breath‐holding (apnoea) that can last up to 25 min with periods of breathing (eupnoea). Our aims were to quantify changes in this behaviour during development and to determine the correspondence between these ontogenetic changes and those independently recorded in the dive durations of free‐ranging seals. We observed 163 seals during periods of apparent sleep, ranging in age from new‐born to adult. at Año Nuevo, California. Mean length of apnoea and percentage time spent in apnoea were 3·1 min and 59%, in neonates (0–4 days old). These values decreased to 1·8 min and 37% in suckling pups (5–28 days old), then increased with age thereafter, reaching about 8·0 min and 60% in adults of both sexes. Sleep apnoea duration and percentage time spent in sleep apnoea increased most markedly after weaning, when the animals were learning to swim and dive. Mean sleep apnoea duration and mean dive duration increased in a similar way during the first year of life; thereafter. mean sleep apnoea duration reached an asymptote while mean dive duration continued to increase. We conclude that the elephant seal's ability to sustain long apnoeas is not only an adaptation for foraging underwater but also a means for conserving water and energy while fasting on land.
Spatial organization and recruitment of lynx (Lynx lynx) in a re‐introduced population in the Swiss Jura Mountains
Authors: Breitenmoser Urs , Kavczensky Petra , Dötterer Michael , Breitenmoser‐Würsten Christine , Capt Simon , Bernhart Frank , Liberek Martin
Published: March 2009

We monitored seven resident (three males and four females) and six dispersing subadult Eurasian lynx from to in a population that was re‐introduced to the Swiss Jura Mountains in the early 1970s. Home‐range areas of the neighbouring adults were 71–281 km2, and significant core areas 34–252 km2. Males occupied significantly larger areas than females. Home‐range overlap was 9% for neighbouring males and 3%) for females. Core areas of males did touch, but those of females were clearly separated. Each male's home range covered those of one or two females. Population density was 0.94 lynx/100 km2 for resident animals. Pre‐dispersal mortality was estimated to be 50%. Juveniles dispersed from their mothers' home area at the age of 10 months. Of six monitored subadults. only one survived the first year of independence. Human‐caused mortality (traffic accidents. illegal killing) was high. This was also the case among resident adults. This might be a threat to the long‐term survival of the reintroduced population.
Studies on skeleton formation in reptiles: Patterns of ossification in the skeleton of Chelydra serpentina (Reptilia, Testudines)
Authors: Rieppel Olivier
Published: March 2009

Patterns and sequence of ossification are described throughout the skeleton of Chelydra serpentina Linnaeus. Evidence is adduced documenting the decoupling of ossification processes from sequence and patterns of chondrification. Convergence of ontogenetic repatterning in the ossification of the axial skeleton in Chelydra and Squamata is discussed, as are problems of adaptive modification of ossification patterns. The development of a carapace may be correlated with changes of ossification patterns in the postcranial axial skeleton of turtles, but the most striking evidence for the adaptive modification of ossification sequence obtains from a comparison of the limb skeleton and its ossification in Chelydra and in sea turtles
Summer quiescent behaviour of the millipede Ommatoiulus moreleti (Julida: Julidae)
Authors: Bailey P. T. , Kovaliski J.
Published: March 2009

The millipede Ommatoiulus moreleti (Lucas), (Julidae) originates in the south‐west Iberian Peninsula, and has successfully invaded parts of southern Australia with hot, dry summers. The species is inactive in the field during summer but is active in autumn, particularly following rains, and in spring. There is some activity in winter. In this paper, the temperature and humidity determinants of seasonal behaviour are analysed, in particular the conditions causing summer quiescence.

Experiments using a millipede treadmill apparatus at different temperatures at 95% RH showed an almost linear response of locomotor activity with temperature between 3 and 21°C, but when the temperature was increased to 28°C, the millipedes became quiescent. Activity could he restored by reducing the temperature.

When the millipedes were exposed to 45% RH there was comparatively little activity at any temperature. Field evidence indicates ii rapid breaking of quiescence with surface moisture

The success of O. moreleti in invading the surface‐litter habitat in South Australia can he explained by its ability to avoid desiccation; its adaptations include its quiescent behaviour during summer and its ability to moult from a winter (reproductive) to B summer (non‐reproductive) form.
Growth, body condition and demography of wild banteng (Bos javanicus) on Cobourg Peninsula, northern Australia
Authors: Choquent David
Published: March 2009

Growth, body condition and demography of a sample of 125 banteng, Bos javanicus, from a largely unharvested wild herd on Cobourg Peninsula in northern Australia were examined. Growth (measured as changes in age‐specific head‐length) was sexually dimorphic, males growing faster and attaining larger sizes than females. Females reached maximum size in three to four years, and males in five to six years. Body condition (measured by the kidney‐fat index) was low amongst juveniles, increasing into middle age. Condition of aged females showed a marked decline. Males attained sexual maturity between three and four years, females between two and four years. Fecundity declined in older females. Breeding was seasonal, mating activity peaking during October and November, with births most frequent between June and August. Mortality amongst calves was high over the first six months of life, declining rapidly amongst older animals. Comparison of demographic data with those reported for captive herds indicates that the wild banteng in this study matured later, were less fecund, and suffered a higher rate of juvenile mortality. Lower fecundity and higher juvenile mortality were associated with patterns of age‐specific body condition, suggesting that food availability was the major factor affecting demography and hence rates of change in banteng abundance.
Comparative quantitative histology of mammalian growth plates
Authors: Kirkwood J. K. , Kember N. F.
Published: March 2009

Variation in the growth rate of long bones is a function of the number of dividing cells in the columns of the proliferation (flat) cell zone of the growth plate, the frequency with which they divide, and the size to which they grow prior to ossification. In a previous study we found that the wide variation in bone growth rates seen among species of birds was largely associated with variation in the numbers of cells in the flat cell zone. Here we have undertaken a similar study of the growth plates of mammals and have examined variation in the morphology and cell kinetics of the tibial growth plates of a variety of species. The bone growth rates tended to he lower than those observed in birds and were particularly low in the anthropoid primates. Although quite marked variation in flat cell numbers is apparent, the results suggest that variation in cell division rate may play a relatively greater role in variation in bone growth rate among mammals than it does in birds. and that the very low hone growth rates seen in the primates are due, in part, to lower rates of cell division than in other species.
Reproductive success in the mandrill, Mandrillus sphinx: correlations of male dominance and mating success with paternity, as determined by DNA fingerprinting
Authors: Wickings E. J. , Bossi T. , Dixson A. F.
Published: March 2009

Considerable controversy exists concerning possible effects of sexually selected phenotypes via intermale competition on reproductive success. The mandrill (Mandrillus sphinx) is an extreme example of evolution by sexual selection, and hence we have studied a semi‐free‐ranging colony of mandrills in Gabon to gather information on male rank, mating success and paternity, as determined by DNA fingerprinting. Two morphological variants or adult male were identified; ‘fatted’ males, with maximum secondary sexual coloration, which occupied dominant positions in the social group, and ‘non‐fatted’ males, with muted secondary sexual adornments, smaller testes and lower plasma testosterone levels, which lived as peripheral/solitary individuals. DNA fingerprinting analyses on infants born over five successive years showed that only the two most dominant, fatted males in the group had fathered off spring. Throughout the annual mating season these males attempted to mate‐guard and copulate with females during periods of maximal sexual skin tumescence. Male rank and mating success were strongly positively related and the alpha male sired 80–100% of the resulting offspring during three consecutive years. Non‐fatted adult males and group associated subadult males engaged in infrequent, opportunistic matings and did not guard females. Loss of alpha status resulted in a fall in reproductive success, but the effect was gradual; the deposed alpha male continued to father 67% and 25% of infants born during the next two years. Thus these results of behavioural and genetic studies on mandrills demonstrate unequivocally that clear‐cut relationships exist between male secondary sexual development, social dominance, copulatory behaviour and reproductive success in the social group.
Nest intrusions, infanticide, and parental care in the burying beetle, Nicrophorus orbicollis (Coleoptera: Silphidae)
Authors: Robertson I. C.
Published: March 2009

Duration of paternal care in the burying beetle Nicrophorus orbicollis Say is highly variable. Both parents bury and defend mouse‐sized vertebrate carcasses as food resources for their offspring, but males abandon their broods several days before females. Nests defended by single female parents were taken over by aggressive conspecifics in live of nine cases, whereas only six of 16 nests defended by both parents were taken over. In the event of a takeover, the intruding beetle replaced the resident beetle of the same sex, destroyed any eggs that were present, and paired with the remaining resident to produce a new clutch. Broods raised by usurpers following takeovers were less successful than broods raised by initial residents on unused carcasses. The majority of takeovers occurred 35 days after carcass burial. The occurrence of nest intrusions by conspecifics did not significantly influence duration of male parental care; when conspecific intruders were excluded from nests males remained with their broods (± S.E.) 11·2 ± 0·8 days (n= 15), and when intruders were added to nests males remained with their broods 12·2 ± 0·6 days (n= 8). Conflict for carcasses intensified in response to larger brood mass, but duration of male care was unaffected by brood mass. Overall. brood mass and the presence or absence of intruders explained only 5% of the variance associated with brood abandonment by males.
Annual cycles of migratory fattening, reproduction and moult in European quail (Coturnix coturnix)
Authors: Boswell T. , Hall M. R. , Goldsmith A. R.
Published: March 2009

Experimental studies of the physiological mechanisms underlying avian migration have concentrated on small passerines. The present study is concerned with the regulation of migratory fat deposition in a galliform. the European quail (Coturnix coturnix). The increased mass associated with migration was due exclusively to the deposition of fat whereas the increased body mass of laying females was due to increases in lean tissue and water as well as fat. Annual cycles of body mass, moult, gonadal size and plasma luteinizing hormone were measured every other week in captive males and females held outdoors under natural daylengths and temperatures in Bristol, UK (51° 27′ N). Males and females showed two peaks of fat deposition each year which occurred at the migratory passage times reported in wild birds. Luteinizing hormone levels and gonadal size increased in parallel with vernal fat deposition, and remained high until late summer. The pattern of primary feather moult in the intact birds was similar to that of wild quail, with moult following gonadal regression and being suspended during autumnal fattening. Castration of European quail did not inhibit the expression of migratory fattening, as it does In certain passerines. In fact, castrates displayed fattening cycles that were more clearly defined and of greater amplitude than those in the intact males. The annual cycle of European quail differs from that of other well‐studied passerine migrants such as Zonotrichia sparrows, and this is most likely associated with differences in breeding ecology. In addition, the ability of quail to express vernal fattening independently of the presence of the gonads suggests that taxonomic differences between migratory species are also apparent in the physiological mechanisms of migratory fattening.
The anatomy, chemical composition and maximum glycolytic capacity of adipose tissue in wild Svalbard reindeer (Rangifer tarandus platyrhynchus) in winter
Authors: Pond Caroline M. , Mattacks Christine A. , Colby R. H. , Tyler N. J. C.
Published: March 2009

Adipose tissue was dissected completely from 21 female and two male Svalbard reindeer killed in the wild in December 1989. The gross mass, mean adipocyte volume, collagen content, the maximum activities of hexokinase and phosphofructokinase and the fatty acid composition of triacylglycerols were measured in samples of adipose tissue from at least 14 superficial, intraabdominal, cardiac and intermuscular depots homologous to those of other terrestrial mammals. The total adipocyte complement was calculated from the mass of each depot and its site‐specific adipocyte volume. Almost all the adipose depots found in other terrestrial mammals were present. Site‐specific differences in adipocyte volume were pronounced but, in contrast to other mammals, the glycolytic capacity of intermuscular adipose tissue was only slightly greater than that of other metabolically active depots, possibly because this subspecies does not naturally perform prolonged, strenuous exercise. All metabolically active depots except the cardiac adipose tissue enlarged with increasing fatness, but the superficial depots expanded more than any of the internal depots. Partitioning between anterior and posterior superficial depots was variable, with the posterior depots enlarging slightly more than the anterior depots. The adipose tissue in the hoof and around the eye was metabolically inert, but that of the bone marrow and the knee had low but detectable glycolytic capacity. The hoof and knee depots contained a high proportion of collagen, suggesting that they are load‐bearing structures.

There was no statistically significant correlation between fatness and mean adipocyte volume and differences in fatness were due mainly to differences in adipocyte complement. Cell proliferation may be the principal mechanism of adipose tissue expansion in all superficial, intraabdominal and intermuscular depots studied. The total adipocyte complement was about twice that predicted from allometric equations relating adipocyte complement to body mass in other mammals and did not increase with age. There were no significant differences between lactating and non‐lactating females in any of the parameters measured. The mean volume of intra‐orbital adipocytes corresponded closely to that predicted from allometric equations. There were more unsaturated triacylglycerol fatty acids in the outer sides of the superficial depots and in other peripheral sites such as hoof, eye and distal marrow, indicating some biochemical adaptation to cooler peripheral tissues.
Effects of maternal age and condition on parturition and the perinatal period of Antarctic fur seals
Authors: Lunn N. J. , Boyd I. L.
Published: March 2009

The effect of maternal age and condition on the date of parturition and the duration of the perinatal period of Antarctic fur seals at Bird Island, South Georgia, were investigated over three consecutive breeding seasons. Females rear young during a four‐month lactation period in a highly seasonal but predictable environment. Although females may first pup at three years of age, they did not attain full adult size until six years of age; older females (≥ 6 years) tended to be heavier, longer, and in better condition than younger females (3–5 years). Older females returned to breeding beaches earlier and could occupy the most suitable pupping sites, and gave birth when densities of animals on the beaches were low (i.e. more favourable for pup survival). Females that arrived earlier were able to remain ashore longer with their pups prior to departing on their first foraging trips but this was unrelated to either maternal age or condition. Younger females returned later in the pupping season, possibly as a result of late implantation due to smaller energy reserves than older and larger females. In 1990 all females arrived late, were in poorer condition, gave birth to lighter pups, and had shorter perinatal periods. This suggests that not only was implantation late but that females returned to an area of low food availability prior to parturition.
Cephalodiscus graptolitoides sp. nov. a probable extant graptolite
Authors: Dilly P. N.
Published: March 2009

A new species of pterobranch has been found that has features that could resolve the longstanding arguments by palaeontologists about how the fossil graptolites produced their elaborate extra‐corporeal homes. Many complex and biologically highly unlikely solutions previously proposed can be simplified. This animal is probably classifiable as a graptolite and thus a living fossil, representing a group thought to be extinct for 300 million years.
A histochemical comparison of fibre types in the M. pectoralis and M. supracoracoideus of the great skua Catharacta skua and the herring gull Larus argentatus with reference to kleptoparasitic capabilities
Authors: Caldow R. W. G. , Furness R. W.
Published: March 2009

Skuas, which are closely related to gulls, frequently use a specialized feeding method (kleptoparasitism) by which they rob other seabirds of their food. This paper tests the idea that skuas have evolved as specialist kleptoparasites.

The fibre type composition of the M. pectoralis, M. supracoracoideus and M. iliofibularis of a great skua Catharacta skua (Brünn.) and a herring gull Larus argentatus (Pontopp.) was determined by three enzyme histochemical methods commonly used for mammalian fibre classification; the reactions for alphaGPDH, NADH‐TR and mATPase activity.

In both species slow fibres were present only in the M. iliofibularis, and fast twitch glycolytic fibres were not present in any of the muscles. The M. pectoralis and M. supracoracoideus of both species consisted entirely of the fast twitch oxidative‐glycolytic fibres.

The overall metabolic enzyme activities of the muscles were assessed in terms of the proportions of fibres with high, intermediate and low metabolic enzyme activity. The overall levels of oxidative and glycolytic enzyme activity were significantly higher in the M. pectoralis than in the M. supracoracoideus and significantly higher in both of these than in the M. iliofibularis. This was true of both species.

The oxidative and glycolytic activities of all three muscles of the great skua were significantly higher than those of the homologous muscles of the herring gull. This was particularly true of the M. pectoralis and M. supracoracoideus. It is suggested that this difference between great skuas and herring gulls enables the former to be more effective aerial kleptoparasites than the latter.
Density‐related features of natterjack toad (Bufo calamita) population in Britain
Authors: Denton J. S. , Beebee T. J. C.
Published: March 2009

We have studied a series of natterjack populations with varying densities of adults on the three main habitat types (lowland heaths, coastal dunes and coastal marshes) occupied by this species in Britain. Animals were aged by skeletochronology, condition was assessed by measuring weight length ratios in autumn and home ranges were determined by individual‐marking and by radiotelemetry. Female longevity was inversely correlated with population density, but no similar effect was observed for males. Uniformity of growth rates, absolute growth rates and mean condition for both sexes were also inversely related to population density, whereas mean home range showed a positive correlation. Taken together the data indicated that in high‐density populations natterjack toads grew more slowly and erratically, were in poorer condition and foraged much more widely than their counterparts in low‐density populations.
Anti‐predator defences of Argiope appensa (Araneae, Araneidae), a tropical orb‐weaving spider
Authors: Jackson Robert R. , Rowe Richard J. , Wilcox R. Stimson
Published: March 2009

Anti‐predator defence behaviour of Argiope appensa (Fuesslin) (Araneae, Araneidae) was studied in the laboratory. The most frequent response of adults and large juveniles of A. appensa to disturbance was pumping, a behaviour during which this web‐building spider moved its body rapidly up and down with its legs remaining on the silk. When disturbed, small juveniles differed from adult females and larger juveniles by often dropping from the web instead of pumping. Argiope appensa sometimes put its web betweeen itself and stimuli from potential predators by shuttling from one side of the hub to the other. Argiope appensa occasionally tugged on the web but this behaviour appeared to be primarily a component of prey‐catching sequences instead of defence. Experiments were carried out to determine the types of stimuli that elicited pumping. Lightly touching the spider or its web, forcefully hitting the web, and air movement elicited pumping but there was no evidence that chemical stimuli from potential predators were important.
Spring and summer food habits and habitat use of the Europena pine marten (Martes martes) on the island of Micorca, Spain
Authors: Clevenger Anthony P.
Published: March 2009

The food habits and habitat use of pine marten (Martes martesL.) on the Balearic Island of Mincorca were studied from March‐August 1990. In a 28.2 km2area, a series of hiking trails/forest roads were used to collect pine marten faeces bi‐monthly and study te species' differential use of habitats. A total of 28 different food items were identified in 723 faeces. Small mammals were the most important food overall, constituting 34% of the volume During March‐April, small mammals were the principal food consumed (63% of volume), followed by birds (19%). In May‐June, birds were the main food (40%), then small mammals. Plant material and insects were the most important foods in July‐August, both made up 68% of the pine marten diet. The abundance of certain foods and the degree of difficulty in obtaining them appear to be important factors that govern pine marten food selection in Minorca. Habitat use was studied along 12 routes totalling 32.6 km. Pine marten showed preference in March‐April for Coastal Shrubland habitat, while during May‐June they were found most in the Upland Pine type. During July‐August, the Upland Pine and Open Pine habitats were most frequented by pine marten. According to bimonthly food habits data, habitat use seems largely determined by the abundance and availability of their prey items in the available habitat types. Martens may concentrate hunting efforts in areas different from when they are not hunting. The Minorcan pine marten differs from continental populations in its wide use of shrublands, in addition to forests.
Transpiration from othognathous spiders of Thailand and Burma
Authors: Schwendinger P. J.
Published: March 2009

Transpiration rates in dry air (20% RH) were measured in 15 orthognathous spider species (Mesothelae, Mygalomorphae) from Thailand and Burma. The mean weight losses range between 0.1 and 1.9% body weight per hour; they are mostly highter than data from related spiders in the literature. Differences between the species are discussed. Web and burrow architecture of the species, and to a lesser extent their geographical distribution, reflect the specific water relations.
Tooth growth in male Antarctic fur seals (Arctocephalus gazella) from South Georgia: an indicator of long‐term growth history
Authors: Boyd I. L. , Roberts J. P.
Published: March 2009

Growth of upper canine teeth of male Antarctic fur seals (Arctocephalus gazella) which died of natural causes at Bird Island, South Georgia, was quantified from measurements of annual layers in longitudinal sections of teeth. Mean age at death was 7.69±0.07 years and this showed a small but significant increase through the period when samples were collected (1972/73–1988/89). There were significant correlations between morphometrics of teeth and those of seals, suggesting that tooth growth provided an indication of body growth. Tooth growth rate was lowest in seals which died early (age 4 years) and increased with age at death. Changes in the growth pattern of teeth suggested that fur seals which became sexually mature early also died early. Tooth growth layers deposited in each calendar year were compared with the expected layer depth based on a linear relationship between layer depth and age at which each layer was deposited. There was significant variation in the depth of tooth growth layers deposited in different years, suggesting that growth was greater in some years than others. No trends in cohort strengths were detected, but particularly poor years for growth were closely related to years in which reproductive performance was also observed to be low. Variations in growth from 1967/68 to 1987/88 were correlated significantly (P < 0.008) with the Southern Oscillation Index of climatic variation.