bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of individual leopards (Panthera pardus kotiya) using spot pattern variation
Authors: MITHTHAPALA S. , SEIDENSTICKER J. , PHILLIPS L. G. , FERNANDO S. B. U. , SMALLWOOD J. A.
Published: March 2009

Twenty‐one captive leopards (Panthera pardus kotiya) at the National Zoological Gardens in Sri Lanka were individually identified using spot pattern variation, Based on an identification method established for lions (Panthera leo), a code was devised examining 23 variable characters, each of which had one to three values. These characters ranged from number and spacing of muzzle spots to forehead and eye patterns. Correlation among characters to be used for identification was minimized using principal component cluster analysis. The most variable character was chosen from each of eight non‐overlapping clusters, and frequencies were calculated for each character value. The probability of occurrence of a given spot pattern was calculated as the sum of the frequencies of each character value. From this probability of occurrence, the information content, in bits, was computed for each pattern. The number of bits per character was also calculated. Using the binomial theorem, the reliability of identification was estimated as the sum of the probabilities of zero or one individual having an identical combination of character values. These binomial probabilities exceeded 0.99 for 15 out of 21 animals, and 0.95 for all but two. In these two animals, the information content was low (5.99 and 5.50 bits, respectively) compared to the others, in which information content ranged from 6.87–10.86. Although the mean number of bits (8.5) was theoretically sufficient for a 99% reliable identification, it was concluded that supplementation with an additional character would be worthwhile for identification of individual leopards.
Feather structure in flightless birds and its bearing on the question of the origin of feathers
Authors: MCGOWAN C.
Published: March 2009

Of several hypotheses proposed for the origin of feathers two predominate: feathers evolved for flight, or for thermal insulation. The argument is sometimes made that since wing feathers degenerate with flightlessness, their primary function is aerodynamic, supporting the flight hypothesis. Examination of the primary feathers of flightless carinates reveals little evidence of degeneration. Notwithstanding the impropriety of deducing original from present‐day functions, feather structure in flightless carinates does not support one evolutionary hypothesis over any other.

Ratites have markedly different primary feathers from flightless carinates and this might be attributable to the longer time since the loss of flight.
Surface‐feeding on cephalopods by procellariiform seabirds in the southern Benguela region, South Africa
Authors: LIPINSKI M. R. , JACKSON SUE
Published: March 2009

Cephalopod beaks recovered from stomach samples taken from 14 seabird species in the southern Benguela region off Southern Africa and from one species at Sub‐Antarctic Marion Island, were identified as far as possible, counted and the lower rostral lengths (LRLs) measured. Dorsal mantle lengths (DMLs) and body masses of the cephalopods eaten were estimated. The results of analyses by percentage frequency of occurrence and numerical abundance are discussed with reference to present knowledge of the distribution of cephalopods eaten by seabirds in the areas studied. Division of the cephalopod component of seabird diets into species which float, and species which sink, after death indicates that the birds forage on dead or moribund cephalopods on the surface, rather than catching live bioluminescent cephalopods at night.
Annual variation in the mating system of the dragonfly Paltothemis Kneatipes (Anisoptera: Libellulidae)
Authors: ALCOCK JOHN
Published: March 2009

The libellulid dragonfly Paltothemis lineatipes exhibits annual variation in male mate‐locating behaviour, variation that appears to be related to changes in the number of males competing in an area. In a year when males were numerous, as reflected in a high rate of male‐male interactions, individuals defended small streamside territories, regularly raided neighbouring territories in an attempt to steal females there, and often were forced off their territory after a few hours of daily ownership. In this year, temporal partitioning of a given site was common, with the same males taking it in turns to defend the location for part of each day. In a year when males were much less numerous, as seen in a very reduced rate of aggressive encounters, males defended territories more than twice as large on average than in the high‐density year; they rarely took females from neighbours, and they much less frequently ‘shared’ ownership of a site with another male on a given day. The changes between low‐ and high‐density years were not associated with a change in average daily copulatory success of territorial males, although the variance in mating success was significantly greater in the high‐density year.
Sexual differences in the absolute growth pattern of the Indo‐Pacific sandy shore crab Matuta lunaris
Authors: BELLWOOD D. R. , PEREZ O. S.
Published: March 2009

The absolute growth pattern of Matuta lunaris (Forskål) is assessed, based on moult increment data and analyses of size frequency distributions. Both sexes show determinate growth with maturity occurring at the terminal puberty moult. However, Matuta lunaris is unusual as the sexes differ markedly in their growth patterns. Males mature at a larger size than females and grow to a larger maximum size. Male growth is characterized by relatively constant moult increments and an unknown and possibly variable number of immature instars with widely overlapping size ranges. In contrast, female growth is characterized by relatively large moult increments and a fixed number of instars, each with restricted size ranges.
Morphological and biochemical variation in populations of Dugesia (G.) tigrina (Turbellaria, Tricladida, Paludicola) from the western Mediterranean: biogeographical and taxonomical implications
Authors: RIBAS MARIA , RIUTORT MARTA , BAGUÑA JAUME
Published: March 2009

Dugesia (Girardia) tigrina is a Nearctic freshwater triclad native to North America, now amply distributed in most European countries as the result of a reportedly unique introduction into north‐west Europe early this century and its dispersal southwards and eastwards in the last decades. All European populations described so far are externally spotted, with a pigmented pharynx, and, apart from two sexual populations recently described in England, they are fissiparous. This uniformity contrasts with the variability reported in its native area, thus supporting the hypothesis of a single introduction. However, thorough morphological, karyological and biochemical comparative studies of European populations have never been properly done.

We have undertaken such a study comparing 24 populations present in a restricted area of the western Mediterranean. The results show an unexpectedly ample variation in external and pharyngeal pigmentation patterns, the presence of sexually reproducing populations, and ample variation in their biochemical patterns as revealed by isoelectric‐focusing. This is an indication that European Dugesia (G.) tigrina is far more diverse than previously thought, suggesting that several, independent introductions from its native area have recently occurred, and the implications of these findings in biogeographical and taxonomic terms are discussed.
Gonadal development and differentiation in Alligator mississippiensis at male and female producing incubation temperatures
Authors: Joss J. M. P.
Published: March 2009

The development and differentiation of the gonads of embryonic alligators incubated at 30 °C (100% female producing) and 33 °C (100% male producing) was investigated histologically. The stage of development of the gonad and differentiation into an ovary or a testis occurred at essentially the same time at both temperatures. This contrasts with the overall development of the embryos which was slower at the lower temperature. A few days prior to differentiation, gonads grew more quickly at 33 °C than they did at 30 °C. However, once differentiated into a presumptive testis, gonads reduced in volume so that at hatching presumptive testes were smaller than presumptive ovaries. It is hypothesized that synchrony/asynchrony of development of the gonad and the rest of the embryo may account for temperature‐dependent sex determination.
Nest location by spool‐and‐line tracking of dasyurid marsupials in New Guinea
Authors: WOOLLEY P. A.
Published: March 2009

Spool‐and‐line tracking was used to study the nesting habits of three species of dasyurid marsupial, tentatively identified as Murexia longicaudata, Antechinus naso and A. habbema. Five nests were located; those of M. longicaudata (two individuals) were arboreal and those of A. naso (one individual) and A. habbema (two individuals) subterranean. The roughly spherical nests, approximately 20 cm in diameter, were formed of interwoven plant material (broad leaves, bamboo leaves and ferns). Arboreal nests had a single entrance hole on one side. Subterranean nests were situated from 65 to 100 cm below the ground surface and they were reached through tunnels approximately 4 cm in diameter. Only A. habbema was found nesting communally. All nests contained a variety of invertebrates. The leaf composition and invertebrate fauna of the nests are tabulated.
Minicia marginella (Araneae: Linyphiidae), a spider new to Britain, from the Channel Tunnel site
Authors: SNAZELL R.
Published: March 2009

In the summer of 1987 a project was initiated to study certain aspects of the environmental impact of tunnelling for the Channel Tunnel. The study areas were situated in East Kent between Dover and Folkestone. At one of the chosen study sites, a male and female of the linyphiid spider Minicia marginella (Wider), hitherto unknown from Britain, were taken in pitfall traps. Both sexes of the species are described and illustrated from the British material.
Characteristics of parotid saliva from the common wombat (Vombatus ursinus)
Authors: Beal A. M.
Published: March 2009

Saliva was collected from the parotid glands of anaesthetized common wombats (Vombatus ursinus) to ascertain the maximal flow rates, salivary composition and possible adaptations to the diet. After temporary catheterization of the parotid duct through the oral opening, salivary secretion was evoked by ipsilateral intracarotid infusion of acetylcholine at varying rates to produce salivary flow rates ranging from 0.017±0.0012 ml.min‐1(0.62±0.037 μmin‐1.kg‐1body weight) to 2.00±0.148 ml.min‐1(70.5±3.21 μl.min‐1kg‐1body weight). The concentrations of Na (22.2±5.50 to 107.0±5.2 mmol.1‐1) and H+ (12.5±1.73 to 17.4±1.40 nmol‐1‐1) were positively correlated with salivary flow rate. The concentrations of K (99.3 ± 6.51 to 13.7±0.62 mmol.1‐1), Ca (1.36±0.229 to 0.74±0.021 mmol.1‐1), Mg (1.14±0.092 to 0.03±0.002 mmol.1‐1), HCO3(65.3±2.43 to 55.7±1.70 mmol.1‐1), PO4(3.30±0.334 to 0.51±0.038 mmol‐1‐1), protein (2.08±0.284 to 0.49±0.084 g.1‐), amylase activity (6.75±1.515 to 1.97±0.538 mkat.1‐1) and urea (10.9±0.89 to 3.88±0.28 mmol‐1‐1) were negatively correlated with flow rate. The relationships between salivary flow and C1 concentration or osmolality were diphasic: negative at low flows and positive at high flow rates. The patterns of excretion of the major anions in the saliva differed substantially from those reported for parotid glands of other marsupials. The saliva had levels of amylase activity which were far higher than those of other marsupials and which may be an adaptation to a diet rich in carbohydrate. Salivary Na/K ratios were not decreased by high‐rate intracarotid infusion of aldosterone (80–100 μg.h‐1for 4 h) which indicated that the wombat gland, like the parotid glands of macropods, requires chronic exposoure to high levels of mineralocorticoides to sensitize the gland.
Variation in the calorific value and total energy content of the lesser sandeel (Ammodytes marinus) and other fish preyed on by seabirds
Authors: Hislop J. R. G. , Harris M. P. , Smith J. G. M.
Published: March 2009

Wet and dry calorific values (energy densities) and total energy content of lesser sandeel Ammodytes marinus, sprat Sprattus sprattus, Atlantic herring Clupea harengus, whiting Merlangius merlangus, saithe Pollachius virens and cod Gadus morhua, were measured. Calorific values varied both within and between species. Larger fish tended to have higher calorific values than small ones, particularly when considered in terms of wet weight, but there was considerable temporal variation. The calorific values and body weights of sandeels larger than 10 cm showed marked seasonal trends and in consequence the total energy content of a sandeel of given length in summer is approximately double the spring value. The calorific values of herring and sprat also varied from month to month but seasonal cycles were less obvious. Whiting varied least. Both calorific values and total energy content of individual sprat were very variable in summer (the spawning season of this species). Because there is so much intraspecific variation, care must be taken when assessing the relative merits (in terms of energy) of different species as prey. The practical difficulties of obtaining reliable data on wet calorific values are discussed and the use of dry calorific values and dry weight/length relationships is recommended.
Morphological and steroidogenic assessment of ovarian activity during lactation in the spotted hyaena (Crocuta crocuta)
Authors: Jaarsveld A. S. van , Lindeque M. , Skinner J. D.
Published: March 2009

Histological evidence suggests that the spotted hyaena (Crocuta crocuta) is polyoestrous, and that corpora lutea are persistent and are not visible after one birth interval. Multiple generations of corpora lutea therefore represent recurring ‘infertile’ oestrous cycles. Plasma oestradiol‐17β and progesterone concentrations fluctuate concurrently, with the highest concentrations occurring during pregnancy. The reduced mean oestradiol‐17β concentrations observed during lactation suggest reduced ovarian steroid secretion during this reproductive phase. However, signs of follicular activity in some lactating females indicate that endocrine activity may still occur during lactation. The presence of multiple ‘infertile’ cycles and some degree of follicular development during lactation explains the ability of this species to fall pregnant soon after the loss of a litter, and provides a mechanism for overcoming the low recruitment rate so characteristic of this species.
Kinematics of prey processing in Chamaeleo jacksonii: conservation of function with morphological specialization
Authors: So K‐K. J. , Wainwright P. C. , Bennett A. F.
Published: March 2009

This study develops a model of prey processing behaviours in lizards of the family Chamaeleonidae based on a kinematic analysis of videotaped feeding sequences in a representative species, Jackson's chameleon (Chamaeleo jacksonii). High‐speed video (200 fields per second) and a computerized image analysis system were used, respectively, to film and quantify sequences of three individuals feeding on crickets. Two behaviours, chewing and prey transport, were identified a priori and compared in detail. Analyses of variance revealed significant differences between the two behaviours in seven of 11 kinematic variables. Patterns of correlation of variables within the entire data set were similar to correlations within each behaviour. A principal component analysis on the kinematic variables provided complete separation of the two behaviours in multivariate space. Chewing is distinct from prey transport behaviour in several ways: (1) chewing lacks extensive posterior movement in the hyoid skeleton while the jaws repeatedly open and close against the prey; (2) there is greater mouth opening in chewing; and (3) the entire gape cycle and its components occur more quickly in chewing. Prey transport involves extensive anterior posterior movements of the hyoid skeleton, which reflect the function of the tongue in transporting the prey from the oral cavity into the oesophagus. In both behaviours mouth opening is primarily associated with lower jaw depression rather than head elevation. Maximum hyoid retraction always occurs after peak gape is achieved. The body and head remain stationary with reference to the background, hence no inertial transport occurs. The kinematic profile of prey transport is compared to published feeding cycles of other iguanian lizards and a generalized model of prey processing in amniotes. Prey transport in chameleons follows the same kinematic patterns as reported for other iguanian lizards. We conclude that chameleons possess a generalized food processing system characteristic of other iguanian lizards, largely unmodified despite the presence of an extraordinary prey capture behaviour and its associated morphology.
Ontogeny of agonistic behaviour in the territorial damselfly larvae, Xanthocnemis zealandica (Zygoptera: Coenagrionidae)
Authors: Rowe R. J.
Published: March 2009

The ontogeny of agonistic displays associated with territory maintenance by Xanthocnemis zealandica larvae is described. Display repertoire and patterns of display use shift as larvae develop from second‐instar to final‐ (=c. 14th) instar. Displays and frequency of display use change, consistent with the developing sensory capability of the growing larvae. Repertoire size does not change markedly during development but there is almost complete turnover in the set of most frequently used displays. The opportunity is taken to correct descriptions of some behaviours observed in small larvae.
Habitat use and ranging behaviour of the red fox (Vulpes vulpes) in a Mediterranean rural area: is shelter availability a key factor?
Authors: Lucherini M. , Lovari S. , Crema G.
Published: March 2009

Factors affecting activity, habitat use, and home‐range size of the red fox were analysed in a highly heterogeneous rural environment. Individual differences in behaviour were used to test our hypotheses. Food habits tended to depend on food availability, which, in turn, was mainly influenced by temperature. Diet was highly heterogeneous. Insects, e.g. grasshoppers and beetles, and cultivated fruits were the staple of the diet, but no diet component stood out clearly from all others. For an opportunistic species such as the fox, habitat heterogeneity may be the main factor underlying a wide trophic niche. All foxes selected the vineyard as part of their home ranges, whereas they preferred for activity the abandoned olive‐yard among the habitats of their home ranges. Human intolerance of foxes affects their pattern of activity, habitat selection, and ranging behaviour. Foxes were strongly nocturnal. Cover‐rich habitats were preferred for resting and for movements in daylight. Areas under human management were mainly used at night. Selectivity was higher for resting than for activity sites. Variation in home‐range size and shape can be influenced not only by the dispersion of the main food patches, but also by the location of shelters
Diet of the golden‐tipped bat Kerivoula papuensis (Microchiroptera) from north‐eastern New South Wales, Australia
Authors: Schulz M. , Wainer J.
Published: March 2009

The diet of the golden‐tipped bat (Kerivoula papuensis) was investigated by collecting faecal samples from captured individuals in the Richmond Range State Forest, north‐eastern New South Wales, Australia. Faecal analysis was used so that all captured individuals could be released after processing and banding. A total of 53 faecal pellets were collected in the summer and autumn months from 39 individuals. The major food of K. papuensis were spiders (Araneida) comprising 91.9% of the total volume of food. Other foods consumed in small quantities were Coleoptera, Lepidoptera and Diptera.
Male roosting habits and mating behaviour of Myotis myotis
Authors: Zahn Andreas , Dippel Barbara
Published: March 2009

Attic‐dwelling male Myotis myotis use different roost sites, but prefer one (or a few) of them and visit others sporadically. Roost‐site preference can change, especially during the mating season. The males use their roost sites over years. Mean occupancy of all roost sites shows a maximum during the mating season. Females of different nursery colonies meet at male roost sites as far as 12 km from their colonies. They stay, on average, four days with one male, may join several males during one mating season and may visit their mating sites over years. Males appear to show no special behaviour to attract females but extend the time they are present at the roost site during the mating season. Each male is visited by about seven adult mates, on average. Differences in reproductive success are indicated by the times males were joined by females and by the numbers of mates and copulations. Two typical mating postures, copulation and five different social calls are described. Since females of different colonies meet at the male roost sites, the mating system of Myotis myotis may favour genetic exchange between colonies.
Integumentary structure and its relationship to wiping behaviour in the common Indian tree frog, Polypedates maculatus
Authors: Lillywhite H. B. , Mittal A. K. , Garg T. K. , Agrawal N.
Published: March 2009

Skin of the Indian tree frog, Polypedates maculatus (Rhacophoridae), was studied in the context of self‐wiping behaviour which functions to expel and distribute cutaneous secretions recently shown to retard evaporative water loss. The secretions contain both mucus and lipids and are derived from a common gland considered to be homologous with characteristic anuran mucous glands. The glands are bipotent and secrete both mucus and lipoid products which are evidently mixed within the glandular lumen. Another type of gland resembling characteristic anuran serous (or granular) glands is found in dorsal but not ventral skin, whereas the lipid‐secreting mucous glands are found in skin associated with all body surfaces. There is no distinct, lipid‐secreting gland present in the skin of this species other than the mucous glands. These histochemical data complement the earlier finding that resistance to evaporative water loss in this species is relatively small compared with phyllomedusine 'waterproof frogs which also exhibit wiping behaviour associated with secretion of lipids. Thus, wiping behaviour may have evolved in association with mucous secretions before dominant lipoid secretions resulted from strong selection for water conservation.
Redescription of Naja siamensis (Serpentes: Elapidae), a widely overlooked spitting cobra from S.E. Asia: geographic variation, medical importance and designation of a neotype
Authors: Wüster W. , Warrell D. A. , Cox M. J. , Jintakune P. , Nabhitabhata J.
Published: March 2009

The Indochinese spitting cobra, Naja siamensis Laurenti, 1768, is redescribed. In order to avoid future confusion with other Asiatic Naja species, and to fix this scientific name irrefutably, we designate a neotype for this species, and designate the same specimen as neotype for the junior synonym Naja naja isanensis Nutaphand, 1982. The pattern of geographic variation in this species is investigated by means of multivariate analysis of morphological characters. We summarize the literature concerning this species, with particular emphasis on separating information concerning N. siamensis from that relating to other Asiatic cobra species. This species is of considerable medical importance, and we present case histories of local envenoming and snake venom ophthalmia.
Weight change and the body reserves of female blue tits, Parus caeruleus, during the breeding season
Authors: Woodburn R. J. W. , Perrins C. M.
Published: March 2009

A female blue tit lays a large clutch that is commonly heavier than her own body weight. Body reserves cannot provide for the entire clutch and little is known of the importance of these reserves during the breeding season. This study reports on weight changes in adult female blue tits during the breeding season, observed by the use of electronic balances. In addition, data from dissecting 67 adult female blue tits, at different stages of the breeding cycle, were used to investigate the changes in body weight. There was a rapid increase in body weight during a period of 4–5 days before the first egg was laid, which was explained mostly by the development of the oviduct and the production of an egg on the final day. Body weight remained constant during the laying period, before decreasing by approximately one gram after clutch completion, owing to the absence of an egg and the absorption of the oviduct. Body reserves increased during the day after clutch completion, were maintained throughout the incubation period and were mobilized during the first five days of the nestling period. Breeding female blue tits appear to deposit small body reserves to act as a short‐term buffer against adverse conditions or to support the brooding phase.
Home range, activity and movements of a wolf pack in central Italy
Authors: Ciucci P. , Boitani L. , Francisci F. , Andreoli G.
Published: March 2009

Home range, habitat use, activity and movement patterns were studied in a pack of wolves in a mountainous region of Abruzzo, central Italy from June 1986 to March 1987. The home range, estimated by the minimum convex polygon from 421 radio locations, measured 197 km2and comprised several infrastructures and areas of human presence, including four garbage dumps and two offal sites. Core areas, calculated by the harmonic mean method, were located toward the centre of the home range where human disturbance and road density were lowest but forest cover was highest. During the time‐span of the study, home‐range use and movement patterns suggested a marked centrality in spatial behaviour and traditionality in retreat areas year‐round, both during pup‐rearing season and the following months. In addition, by being essentially nocturnal, resident wolves appeared to adopt tactics of temporal segregation from people to exploit food resources safely in the proximity of human settlements. Overall activity correlated with distance travelled (r = 0.90,P<< 0.001), and corresponded to cyclic nocturnal movements from retreat to feeding areas. Wolf movement rate between 20:00 and 04:00 h averaged 2.5 km/h but varied up to about 8 km/h, and daily distance travelled (x̄= 27 km/night; range 17–38 km/night) mostly depended on the location of traditional feeding sites. Home‐range configuration, habitat use, activity and movements all appeared highly integrated so as to represent the most functional compromise between avoidance of human inteference and exploitation of the available food resources.
Mortality of lemmings, Lemmus lemmus, at peak density in a mountainous area of Norway
Authors: Steen H. , Holst J. C. , Solhøy T. , Bjerga M. , Klaussen E. , Prestegard I. , Sundt R. C. , Johannesen ø.
Published: March 2009

We estimated carcass density and determined cause of death in a peak‐density lemming, Lemmus lemmus, population at Finse, Norway. Of 74 recovered carcasses, 80% had subcutaneous haematoma (blood underneath the skin) in the head region, though the skin on the skull most often appeared unharmed. Thirty percent were apparently killed by a mustelid predator, while 51% were probably killed by corvids. Carcass density was 26.6 and 9.4ha‐1 in good and poor lemming habitats, respectively.
Seroepidemiology of rabbit haemorrhagic disease (RHD) in wild rabbits (Oryctolagus cuniculus) in the United Kingdom
Authors: Trout R. C. , Chasey D. , Sharp G.
Published: March 2009

An extensive collection of blood samples from adult wild rabbits, from areas where Rabbit Haemorrhagic Disease (RHD) had not been recorded, was obtained from sites across the U.K. and parts of Eire over the winter of 1994/95. Sera from 946 animals were examined for antibodies to RHD. Antibody was found in all populations, varying between 20 and 100% depending on locality, and overall 64% of rabbits were seropositive in midwinter, supporting the view that non‐pathogenic RHD or RHD‐like caliciviruses, which are not producing clinical disease, circulate within rabbit populations. The serological response to these agents appears to confer significant immunity on rabbits subsequently exposed to the virulent RHD virus, so the disease will not be as devastating as myxomatosis was in the early 1950s (99% mortality) but at least one‐third of the c. 40 million rabbits in the U.K. are susceptible.
Diet of feral house cats Felis catus, ferrets Mustela furo and stoats M. erminea in grassland surrounding yellow‐eyed penguin Megadyptes antipodes breeding areas, South Island, New Zealand
Authors: Alterio N. , Moller H.
Published: March 2009

Spring and summer diets of feral house cats (Felis catus), ferrets (Mustela furo) and stoats (M. erminea) were studied in grassland surrounding breeding areas of yellow‐eyed penguins (Megadyptes antipodes), a regionally threatened native species. All three predator species ate large numbers of young rabbits (Oryctolagus cuniculus) and birds. Stoats also relied heavily on mice (Mus musculus). Use of rabbits increased in rank order of increasing predator size, and male stoats ate more lagomorphs than female stoats. Diet differences may reflect character displacement as a result of exploitation competition, but interference competition or predation may force the smaller species to exploit micro‐habitats with increased ground cover and consequent increased availability of smaller prey. Reduction of predation of native species like yellow‐eyed penguins by decreasing or increasing staple mammal prey numbers of the introduced predators may provide lasting conservation benefits, but could also trigger diet changes that increase risk to endangered wildlife.
Habitat suitability in muskrats: a test of the food limitation hypothesis
Authors: Virgl J. A. , Messier F.
Published: March 2009

Data on habitat selection, overwinter survival, and litter survival rate of muskrats indicate that fitness differs among habitats in marsh environments. We measured nine nutrient‐dependent phenotypic variables of muskrats and one independent assessment of forage quality during the ice‐free period (May‐October) from 1992 to 1994. Data were used to test the hypothesis that differences in food resources limit the demographic performance of muskrats in marginal versus prime habitats (food limitation hypothesis, FLH). None of the null predictions relating habitat quality with reproductive parameters could be rejected statistically. Adult body mass and length were greater in prime habitats, but fat content did not differ, which suggested that the difference was associated with larger structural size of dominant animals in prime habitats. Growth rate of weaned juveniles was not different among habitats, which represented the strongest evidence for rejecting the FLH. Faecal crude protein content, which was used as an index of quality of food ingested, was marginally different between the two most suitable habitats, but the direction of the difference did not support our prediction. Overall, the temporal variation in faecal crude protein content was similar among habitats. We conclude that food is not a key factor limiting the demographic performance of muskrats among habitats during the ice‐free season.
Two new species of Phoridae (Diptera) whose larvae associate with large spiders (Araneae: Theraphosidae)
Authors: Weinmann D. , Disney R. H. L.
Published: March 2009

Two new species of Megaselia Rondani, M. dinwrphica Disney and M. praedafura Disney, are described from South America. Their larvae crawl around on the bodies and exuviae of Theraphosidae. Larvae of M. praedafura were observed moving on to the spider's prey while it was engaged in feeding from the same prey.
Development of electrical signalling in larvae of the African fish, Pollimyrus adspersus (Mormyridae, Teleostei): the patterns of interdischarge intervals
Authors: Kramer Bernd , Postner Martin
Published: March 2009

The ontogenetic development of the overt motor and the electrical signalling behaviour in larvae of a West African elephantfish, Pollimyrus adspersus, were studied. At an age of 35–40 days, hovering in mid‐water was first observed. Before that time, the larvae moved only occasionally and rested in the nest that was guarded by the male parent. The very low electric organ discharge (EOD) rate of 2.4 ± 0.9 Hz observed in 8‐ to 10‐day‐old larvae (that generate their first EODs on day 8) increased to an adult rate of 8.4 ± 1.7 Hz in 21‐ to 25‐day‐old larvae. Even 8‐ to 10‐day‐old larvae generated a trimodal inter‐EOD interval distribution (with three distinct discharge rates), similar to that observed in adults, although larval interval modes were of much longer duration. For the first (high rate) mode, the trend towards shortening stabilized already at the age of 21–25 days, whereas for the second and third (low rate) modes, this occurred only at an age of around 61–70 days.

Inter‐EOD interval patterns recorded during swimming behaviour of 8‐ to 10‐day‐old larvae closely resembled that observed in juveniles (exceeding 100 days): there was a single mode only, and EOD rate was increased (13.1 ± 3.2 Hz).

Artificial stimulation with natural inter‐EOD interval patterns previously recorded from other larvae or the nest‐guarding male did not evoke any responses in 14‐day‐old larvae, apart from a brief EOD stop response to stimulus onset. However, even in larvae as young as 11 days, Preferred Latency Responses of their EODs to an artificial series of stimulus pulses (constant rate of 5 Hz) were observed at a stimulus intensity of 120 μVp‐p/cm. In the youngest larvae, 36‐ms latencies were most frequent; this shortened to 19 ms in 31‐day‐old larvae (approaching the adult value; Kramer, 1978). The time pattern of EOD generation in P. adspersus larvae resembled that in mature specimens even before the adult electric organ became functional.
Sexual dimorphism in northern temperate spiders: implications for the differential mortality model
Authors: Prenter J. , Montgomery W. I. , Elwood R. W.
Published: March 2009

We examined sexual size dimorphism in 627 species from 123 genera and 32 families of northern temperate spiders from Great Britain and Ireland with different life histories, using phylogenetically independent contrasts. Web‐building and non‐web‐building, sit‐and‐wait predators were compared with non‐web‐building, active hunting spiders. After accounting for phylogenetic effects, we find no evidence of differences in sexual size dimorphism in northern temperate spiders with differing life history/predatory strategies. We discuss the implications of our findings for the generality of the differential mortality hypothesis (Vollrath & Parker, 1992) with respect to spiders with different predatory modes from different habitats and environments. This recent theory proposed that extreme sexual dimorphism in spiders resulted from differential adult mortality as a consequence of different adult life histories. We conclude that this model cannot explain the less extreme dimorphism found in temperate spiders.
Haul‐out and diving activity of male Atlantic walruses (Odobenus rosmarus rosmarus) in NE Greenland
Authors: Born E. W. , Knutsen L. Ø
Published: March 2009

During August‐September 1989 and 1990, movements, haul out and dive activity of male Atlantic walruses (Odobenus rosmarus rosmarus L.) were studied at a terrestrial haul‐out site situated in an inshore foraging area in NE Greenland at 76± 30′ N. Data were collected from direct observations of a group of about 50 males during August, including walruses that could be individually identified from natural markings, and from tracking of 8 adults equipped with satellite‐linked radio transmitters during August‐September. In both years, instrumented walruses hauled out for a total of 29.3% of the sampling time. In 1989, when ice floes were available for hauling out, the walruses spent 11% of the time on ice, whereas in 1990, when ice was absent from the study area, they only hauled out on land. Duration of haul‐out periods, which did not differ between months or years, averaged 11 h (0.46 d) on ice (S.D. = 5.9, range: 1–29 h, n= 19 periods), and 38 h (1.6 d) on land (S.D. = 11.7, range: 13–64 h, n= 43). The walruses mainly hauled out during the afternoon and evening. Numbers hauling out on land during August were negatively correlated with wind direction, precipitation (rain) and wind‐chill. In 1989, the duration of periods of absence from the terrestrial haul‐out site (i.e. presumed foraging trips) averaged 206 h or 8.5 d (S.D. = 106.9, range: 48–412 h, n= 13), whereas, in 1990, such trips averaged only 81 h or 3.4 d (S.D. = 37.9, range: 24‐156 h, n= 24), reflecting that walruses used the haul‐out site more frequently when ice was absent. Direct observations of foraging walruses showed that they were submerged about 81% of the time.
ZSL Scientific Meetings: short reports Sexual selection, genetic variation and speciation
Authors: Cotgreave Peter
Published: March 2009

Rudyard Kipling was able to explain “How the Leopard got its Spots” and “How the Rhino got its Skin”, but he did not offer any clue as to “How the Peacock got its Tail”, which is an issue that has long taxed the minds of evolutionary biologists. In fact, the males of many animal species produce extravagant ornaments that appear to serve no really useful purpose. We know that, at least in some cases, these flamboyant displays are to do with sexual selection; they are used by females in making their choice of mates. However, we do not understand the consequences of such behaviour for other evolutionary topics.
Conservation of deer: contributions from molecular biology, evolutionary ecology, and reproductive physiology
Authors: Jabbour H. N. , Hayssen V. , Bruford M. W.
Published: March 2009

Molecular phylogenetics, interspecific comparisons, and assisted reproductive techniques are recent approaches to understanding and facilitating conservation of endangered species. This paper reviews the contribution of these approaches to a small but well‐studied group of mammals, deer, many of which are endangered in the wild. Conservation efforts require a comprehensive understanding of the biology and history of these animals. The value of assisted reproductive technologies for conservation of deer has received increased awareness especially for captive populations. Such breeding programmes are designed to assist propagation of threatened species and to maximize genetic diversity within populations through the movement of genetic material across the globe, but will only be successful if we understand the genetic and reproductive potential of various lineages. Here we discuss the phylogenetic status of deer, the distinctiveness and evolution of their reproductive patterns, and current approaches for improving the success of controlled breeding programmes for the conservation of endangered lineages. Only by combining both theoretical and practical approaches to conservation efforts can we hope to salvage the remaining organismal diversity of our planet.
Reproduction in the female Angolan free‐tailed bat, Tadarida (Mops) condylura (Microchiroptera: Molossidae), in the eastern Transvaal, South Africa
Authors: Vivier L. , Merwe M.van der
Published: March 2009

The reproductive pattern in the female Angolan free‐tailed bat, Tadarida (Mops) condylura (A. Smith, 1833), was studied at two localities in the eastern Transvaal during the period 1988–1990. Reproduction in female T. condylura was seasonally polyoestrous. Females displayed a bimodal reproductive pattern, with reproductive activity extending from early September to early May, followed by reproductive quiescence from May to August. The interval between the two reproductive cycles was marked by a post‐partum oestrus with adult females becoming pregnant one to three weeks after parturition while still nursing their young. Females become sexually mature during their first year with some only undergoing one pregnancy. Gestation and lactation periods were 85 days and 50–60 days, respectively. Females displayed dextral dominance with regard to the morphology and function of the ovary and uterus.
Testes weight, body weight and mating systems in marsupials and monotremes
Authors: Rose R. W. , Nevison C. M. , Dixson A. F.
Published: March 2009

Relationships between testes weight, body weight and mating systems were examined in 40 marsupial species and in the extant monotremes. Relationships between relative testes weight and mating systems in marsupials resemble those previously described for primates. Thus relative testes weights are greatest in those marsupials where females mate with multiple males during the fertile period, i.e. polyandrous species (e.g. Antechinus ftavipes, Isoodon obesulus, Perameles nasuta, Potorous tridactylus, Macropus eugenii and M. agilis) and smallest in monandrous forms (e.g. Petauroides volans and Petaurus breviceps) where females usually mate with a single male. These findings are consistent with effects of sperm competition upon the evolution of relative testes sizes in marsupials. Where field studies on marsupial mating systems are lacking, we make predictions based upon examination of their relative testes weights. Tarsipes rostratus, Acrobates pygmaeus, Macropus rufogriseus and Sarcophilus harrisii are predicted to engage in multiple matings and sperm competition. Conversely, Lasiorhinus latifrons, Cercatetus concinnus and Pseudoantechinus macdonnellensis are predicted to be monandrous in their mating behaviour. The monotremes (Ornithorhynchus anatinus, Tachyglossus aculeatus and Zaglossus bruijnii) are characterized by possession of very large testes; monotremes are shown to have significantly greater relative testes weights than marsupials, primates or avian species. This taxonomic difference is unlikely to be related lo the occurrence of oviparity or to the abdominal position of the testes in the Monotremata. Their mating systems are not known in detail, but some evidence for multiple matings (and hence for sperm competition) exists for Tachyglossus aculeatus so that their large testes may be adaptive in this context.
Survival and behaviour of castrated Soay sheep (Ovis aries) in a feral island population on Hirta, St. Kilda, Scotland
Authors: Jewell P. A.
Published: March 2009

The free‐living population of Soay sheep on the island of Hirta, St. Kilda, in the Outer Hebrides, has been intensively studied since 1959. The present study was initiated to throw light on the causes of the high mortality rate of adult rams in comparison to that of ewes. In 1978, 1979 and 1980, a total of 72 male lambs was castrated within a day or two of birth. The survival of these castrates has been much longer than that of the entire rams, marked as controls, and longer than that of ewes of the cohorts of the same years. The daily activity pattern of the castrates was similar to that of ewes rather than that of rams. In particular, during the rut the castrates spent most of the daylight hours grazing, in contrast to the rams who were continuously moving and involved in agonistic and sexual encounters. This study substantiates the earlier assertion that the costs in energy of reproduction are a major cause of mortality in temperate zone ungulates. The social organization of some castrates was similar to that of females in that they remained with the home‐range group of ewes into which they were born, but other individuals resembled males in that these castrates clubbed together in their own groups. These patterns of behaviour persisted throughout life.
Spider webs: dew‐loading of the linyphiid sheet‐web
Authors: Brackenbury J. H.
Published: March 2009

When fully dew‐laden the sheet‐web of the spider Frontinellina frutetorum Koch (Araneae, Linyphiidae) stretches by an estimated 66%, well beyond the breadking strain of structural silk threads in air (19–25%). Tests showed that non‐sticky threads of the araneid spider Zygiella x‐notata could stretch by up to 55% after immersion in water. Implications of water‐induced hyper‐elasticity for web design and loading tolerance are discussed.
Factors affecting the difference in foraging success in three co‐existing Cyclosa Spiders
Authors: Miyashita Tadashi
Published: March 2009

Species‐specific differences in prey‐capture success of co‐existing web‐building spiders are derived from complex factors: various web parameters, web placement, and the spider's response to prey. By examining these, this study revealed prey‐capture modes of three species of web‐building spiders of the genus Cyclosa living in the same habitat. Cyclosa octotuberculata and C. argenteoalba showed a greater prey capture rate than C. sedeculata, though size compositions of prey were similar in all species. Cyclosa octotuberculata spins thick silk with large adhesive droplets, which may contribute to the higher stopping and retention abilities of the web. Cyclosa argenteoalba constructs webs at open sites where prey is abundant, and has webs of dense mesh size, which may result in the high stopping ability of webs. In C. sedeculata, the web is less effective for stopping and retaining prey, probably owing to the thin silk with a small amount of sticky material, and the response to prey is not rapid. It seems that the former two species achieve a similar level of foraging success by using different sets of foraging traits and the third species has the disadvantage in most aspects of foraging.
The adaptive significance of monogamy in the golden‐reumped elephant‐shrew
Authors: Gibbon Clare D. Fitz
Published: March 2009

Golden‐rumped elephant‐shrews Rhynchocyon chrysopygus are primarily monogamous, males and females defending joint territories for long periods and probably for life. However, males may occasionally solicit extra‐pair copulations from neighbouring females and annex their territories if the resident male disappears for any reason. Males provide no direct paternal care, and the adaptive significance of monogamy in this species is unclear. Although it is possible that males provide some indirect benefits to the female and her offspring, these are unlikely to be substantial. Males and females spend little time together, so males are unlikely to provide additional protection from predators, and there is no evidence that the presence of a territorial male reduces the costs of territorial defence for the female. Females were able to breed successfully when mated bigamously, demonstrating that the undivided assistance of the male is not essential for successful rearing of offspring. The fact that male elephant‐shrews occasionally attempt to defend more than one female suggests that polygyny would be beneficial for males. However, defending two territories is costly, resulting in increased activity and weight loss, and higher rates of intrusion by neighbouring males. Female elephant‐shrews do not occupy particularly large home ranges for their body size. The results suggest that the high costs of defending a territory large enough to encompass the ranges of more than one female, combined with the greater probability of being cuckolded, make defending more than one female a poor option for male elephant‐shrews.
Description of the mature larva of the waspDinetus pictuswith phylogenetic implications for the tribe Dinetini (Insecta: Hymenoptera: Sphecidae)
Authors: Asís J. D. , Tormos J. , Gayubo S. F.
Published: March 2009

The mature larva of the waspDinerus pictusis described. The ventral position of the anus, the absence of antenna1 papillae, and the weak development of the galeae, together with other minor differences in labrum, epipharynx, and parietal bands, clearly separate the larva ofDinetusfrom those of the tribe Astatini. Larval and adult characters do not support the inclusion of Dinetini in the Astatinae (sensuBohart & Menke, 1976), and provide evidence in support of a relationship with the Laninae‐Crabroninae complex.