bluuebunny/crossref_metadata_2025 huggingface dataset:
Interannual variation in the breeding biology of the Antarctic prion Pachyptila desolata at Bird Island, South Georgia
Authors: Liddle G. M.
Published: March 2009

Interannual variation in aspects of the breeding biology of Antarctic prions was studied for three summers (1989–1992) at Bird island, South Georgia. Egg size, mass and incubation period remained constant. Laying, hatching and fledging were significantly delayed and less synchronous in 1991/92 (range of laying dates 51 days compared to 10–15 days in the two other seasons). This was due to an unusually cold and protracted winter, with ice blocking burrows into the spring, restricting availability of nest sites. Brooding lasted longer in 1991/92 but the overall fledging period was unchanged. Skeletal growth rates did not vary amongst years; growth in mass was slower in 1989/90 but fledging mass was similar in all three years. In 1989/90 and 1991/ 92 later hatched chicks grew (in mass) faster. The survival of chicks from hatching to fledging did not vary amongst years or with hatching date. Feeding frequency was similar between years, once allowance had been made for starlit nights. Thus late and asynchronous breeding in 1991/92 did not result in reduced breeding success either through predation or starvation.

Crustaceans formed 98–99% of the mass of the identifiable portion of regurgitated food samples. Significant annual variation was found within these crustaceans with the presence of krill (least in 1990/91) being inversely related to that of amphipods and copepods. There was no relationship between diet composition and chick growth or survival. Other seabird species, lacking the morphological specialization for feeding on copepods and amphipods, had very low breeding success in 1990/91, when krill was scarce.
Relaxation of reproductive suppression in non‐breeding female naked mole‐rats, Heterocephalus glaber
Authors: Westlin Lilian M. , Bennett N. C. , Jarvis Jennifer U. M.
Published: March 2009

Ninety‐four non‐reproductive female naked mole‐rats, from seven colonies, were studied in terms of vaginal perforation, vaginal smears and urinary concentrations of oestradiol‐17β and progesterone in relation to the time of parturition of the breeding female, the queen. The study concentrated mainly on the period from nine days prepartum to 13 days postpartum of 12 births. Sixty‐eight percent (n= 253) of the non‐reproductive females had detectable urinary concentrations of oestradiol‐17β and many of these had perforated vaginas throughout the study period. These females showed a significantly increased urinary concentration of oestradiol six days prior to parturition of the queen. In females with undetectable concentrations of oestradiol‐17β, the proportion with perforated vaginas increased from six days prepartum (54%) to reach a peak on the day of parturition (92%) of the queen. Urinary progesterone‐concentrations were 0.7nmol/mmol creatinine at some stage in the study period in 90% of the females and scattered short peaks or spikes were experienced by all these females, but without synchronization between the females in a colony and without any detectable correlation with the time of parturition of the queen. Maximal concentrations in some females were comparable to the values in cycling breeding females during the luteal phase, but were of a much shorter duration than in breeding females. Vaginal smears did not show clear cyclic patterns.
Terminal spawning in the deepwater squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae)
Authors: Jackson George D. , Mladenov Philip V.
Published: March 2009

Maturation in the onychoteuthid squid Moroteuthis ingens was found to be irreversible, with death following shortly after sexual maturation and spawning. Both males and females were found with spent gonads. The ovary reaches very large sizes in mature females and probably prevents feeding by constricting the caecum. There was also a marked difference in the tissue integrity between immature females and females which had reached sexual maturity. Mature and spent females showed advanced tissue breakdown with individuals having a thin mantle wall with an inelastic, gelatinous appearance. Histological examination of the mantle wall revealed that the tissue breakdown was due to a drastic histolysis of muscle tissue and, to a lesser extent, collagen fibres. Mature males also showed some tissue breakdown and loss of muscle fibres but this was not as dramatic as in the females. These features are considered in relation to processes contributing to terminal maturation in M. ingens.
Reproduction constrains the use of daily torpor by free‐ranging common poorwills (Phalaenoptilus nuttallii) (Aves: Caprimulgidae)
Authors: Csada R. D. , Brigham R. M.
Published: March 2009

The purpose of this study was to determine if common poorwills (Phalaenoptilus nuttallii) resist entering torpor during the breeding season. During the summers of 1991 and 1992, we studied poorwills in the Cypress Hills, Saskatchewan, Canada, near the northern limit of their distribution. Since poorwills are monogamous and share incubating and brooding responsibilities, we predicted that the non‐incubating or non‐brooding bird would enter torpor when stressed energetically (e.g. on cold and/or wet nights). Individuals carrying temperature‐sensitive radio transmitters entered torpor significantly less often during the breeding season (two of 195 bird nights) than the non‐breeding season (27 of 44 bird nights). During the breeding season we found no birds involved in an active nesting attempt in torpor. We conclude that reproduction constrains the use of torpor by adult birds, but why non‐incubating and non‐breeding birds did not enter remains unclear.
Observations on a mite (Poecilochirus davydovae) predatory on the eggs of burying beetles (Nicrophorus vespilloides) with a review of its taxonomic status
Authors: Blackman S. W. , Evans G. O.
Published: March 2009

Observational evidence is presented suggesting that the mite Poecilochirus davydovae Hyatt (Mesostigmata: Parasitidae) is predatory on the eggs of the burying beetle Nicrophorus vespilloides Herbst and that an increase in numbers of the mite in the laboratory accounts for a reduction in apparent beetle clutch size over successive generations. Morphological adaptations for oophagy are described and physogastry is reported for the first time in the genus Poecilochirus. A new sub‐genus Physoparasilus is proposed for the reception of P. davydovae and P. subterraneus and the female of P. davydovae is redescribed. The implications of the oophagous behaviour of P. davydovae on the mite‐Nicrophorus relationship are discussed.
Flight style in bats as predicted from wing morphometry: the effects of specimen preservation
Authors: Bininda‐Emonds O. R. P. , Russell A. P.
Published: March 2009

An as yet unconsidered potential error in studies that predict flight style from morphological measurements of bats is the effect of the specimen type employed. On the basis of the finding that morphological measurements taken from fluid‐preserved bat specimens may not yield values equivalent to those taken from the live animal, we compared the values of several variables (lifting surface area, wingspan, mass, aspect ratio, wing loading and minimum power speed) for live and fluid‐preserved little brown bats (Myotis lucifugus) with the accepted standards for this species given by Norberg & Rayner (1987). Significant differences were detected for lifting surface area, wingspan, mass, aspect ratio and wing loading values taken from live bats and their respective values reported by Norberg & Rayner. Differences between preserved bats and Norberg & Rayner's numbers were limited to lifting surface area and wingspan (extended wing positions only), aspect ratio (all wing positions), and mass (both 70% ethanol‐ and 45% isopropyl alcohol‐preserved specimens). Thus, Norberg & Rayner's values correspond most closely to values obtained from preserved museum specimens, a fact reflecting the source of their data in this instance. This and other limitations involved in attempting to predict the flight style of bats from a few morphological characters are discussed.
Intraspecific variation in the dolphinsLagenorhynchus albirostrisandL. acutus(Mammalia: Cetacea) in metrical and non‐metrical skull characters, with remarks on occurrence
Authors: Mikkelsen Anna Maria Hill , Lund Anders
Published: March 2009

Intraspecific multivariate data analyses of 27 metrical and 20 non‐metrical characters were performed on skulls ofL. albirostris(Gray, 1846) andL. acutus(Gray, 1826) to distinguish between possible populations from the eastern and the western North Atlantic.

The results from principal component (PC) analysis and partial least square (PLS) analysis suggest that the skulls ofL. albirostriswere taken from separate populations, whereas those ofL. acutuswere not.

A difference in the occurrence‐patterns of the two species was found, indicating that the degree of intraspecific variation may be linked to the water‐depth related distribution.
Postcranial paleoneurology of the Diapsida
Authors: Giffin Emily B.
Published: March 2009

The relationships between the size of the spinal cord and the size of the neural canal, and between gross spinal cord anatomy and locomotor style, were documented in a wide range of living diapsids. Observed relationships were used to make predictions about spinal cord anatomy and about limb use and position in related fossil taxa. In particular, the data suggest that the brachial plexus, and therefore the cervical/dorsal vertebral transition, of the theropod dinosaurs studied was located considerably posterior to its presently accepted location, and that the forelimbs of the giant carnosaurs Tyrannosaurus rex and Carnotaurus sastrei were of biologically insignificant use. Neural canal measurements support previous interpretations of locomotor style in extinct crocodilians, and can be used to predict limb placement in plesiosaurs.
The breeding ecology of Cancer gracilis (Crustacea: Decapoda: Cancridae) and the mating systems of cancrid crabs
Authors: Orensanz J. M. , Parma A. M. , Armstrong D. A. , Armstrong J. , Wardrup P.
Published: March 2009

Brachyuran crabs in the family Cancridae are found in a variety of habitats, ranging from ‘open’ sandy or muddy grounds to ‘structured’ rocky bottoms rich in refuge space. Cancer gracilis Dana inhabits shallow open habitats in the north‐east Pacific Ocean. Females in all reproductive conditions aggregate in relatively small areas, where mating activity appears most intense. Maximum mating activity was observed towards the end of the spawning/hatching season (August). Females play an active role in mating, often initiating interactions with the prospective male partner. Mating in the field was non‐assortative with respect to size. There was no indication of direct mate choice by either males or females; resolution of male‐male competitive interactions was size‐based. Males below minimum mating size (77 mm carapace width) had spermatophores in the vas deferens but did not react to receptive females.

Sperm competition is likely because sperm can be retained across moults and multiple copulations are possible within a receptive period. Female spermathecae are of the ‘ventral’ type (contrary to what has been indicated for cancrids), and during intercourse are beyond the reach of male gonopods. Mechanisms to exclude competing sperm include male‐produced sperm plugs and post‐copulatory mate guarding.

Results are discussed in the context of the ‘structured‐to‐open’ habitat gradient, which may underlay much of the diversity in cancrid reproductive ecology. We argue that, by comparison with C. magister (a larger size sympatric species also found in open habitats), (1) reproductive asynchrony and female gregariousness in C. gracilis increase the environmental potential for polygyny, resulting in a female defence polygynous mating system, and (2) reproductive asynchrony inflates the operational sex ratio, leading to stronger sexual selection.
Comparative external morphology of theConusosphradium (Mollusca: Gastropoda)
Authors: Spengler H. A. , Kohn A. J.
Published: March 2009

The osphradium is larger and more complex inConus, a large and taxonomically difficult genus, than in other prosobranch gastropods. We examined intra‐ and interspecific variation in external anatomical characters of this major chemoreceptor organ, how these relate to ecological characteristics, and the potential of the osphradium to aid taxonomic differentiation, among 22 species ofConus.Six quantitative characters convey the main features of theConusosphradium: its area, width‐length ratio, curvature, orientation relative to the animal's anterior‐posterior axis, density of sensory leaflets, and number of digitiform ridges on sensory leaflets. Species in 85% of pairwise comparisons differed significantly with respect to at least one variable. Multivariate discriminant function analysis successfully differentiated other species. Osphradium size relative to body size varied significantly with habitat type, and number of digitiform ridges varied with food type, but other characters were independent of ecological attributes and may potentially be useful in phylogenetic reconstruction.
Patterns of dispersal and seasonal migration in roe deer (Capreolus capreolus)
Authors: Wahlström L. K. , Liberg O.
Published: March 2009

Roe deer (Capreolus capreolus) spacing behaviour, during the period between mother‐fawn separation and home range establishment, was studied in southern Sweden during 1987–1992. Data were collected, using telemetry, in two non‐hunted populations. Females dispersed either as yearlings, or as 2‐ or 3‐year‐olds after having migrated between non‐overlapping summer and winter ranges for one and two seasons, respectively. Seasonal migration usually ended with permanent settlement in the new summer area. Males dispersed as one‐ or two‐year‐olds, or remained philopatric. Median distance moved was c. 2 km with no significant sex‐bias. Both populations underwent one increase, and one stable phase. During the increase phase, the frequency of yearling dispersal was 70% in one of the populations, but dropped to 20% at high density. This drop paralleled a 14% decrease in yearling winter weights. In the other population, yearling dispersal frequency was 56% during the increase phase. This population stopped increasing at an intermediate density and dispersal frequency was kept at 75%. Weights remained high in this population. In neither of the populations, at intermediate and high densities, was a sex‐bias in dispersal among yearlings evident. Dispersers were on average heavier than philopatrics. High juvenile winter weight did not predestinate yearlings to dispersal, whereas low weight seemed to prevent dispersal. On the basis of these relationships, we propose a hypothesis relating dispersal to body condition, in order to explain dispersal tendency at different population densities. Further, we suggest the reason for female migration is the advantage of residing in a group during winters when predation risk is high. Since it is difficult for females (but not for males) to join non‐relatives, dispersers must go back to the natal area as long as they have too few offspring to form their own matriarchal group.
Does limb length predict the relative energetic cost of locomotion in mammals?
Authors: Steudel Karen , Beattie Jeanne
Published: March 2009

Do relatively longer limbs result in a lower energetic cost of locomotion? To determine whether or not cost is correlated with limb length in some way other than that due to their respective relationships to body mass, we have removed the effects of size by calculating the residuals of the relationship between each character and body size. We then regressed the pairs of residuals on one another. Because biological variables do not occur in a series of units that have evolved independently, the degree of divergence of two species is likely to be influenced by the length of time since they last shared a common ancestor. We therefore corrected for the phylogenetic relatedness of species. Data on the energetic cost of locomotion of a wide variety of species were taken from published sources. Data on limb lengths were taken from specimens in various museum collections which were similar in body mass (± 12%) to the specimens on which the cost measurements were made. None of the correlations between the residuals of either fore‐ or hindlimb length and neither of two estimates of the cost of locomotion was significant atP= 0.05. It is concluded that limb length does not importantly influence an animal's locomotor efficiency. These results do not imply the lack of a close relationship between cost and stride length.
The courtship behaviour of the spotted dusky salamander, Desmognathus fuscus conanti (Amphibia: Caudata: Plethodontidae)
Authors: Verrell Paul A.
Published: March 2009

The courtship behaviour of the North American southern dusky salamander, Desmognathus fuscus conanti (Plethodontidae), is described for the first time. The male is the most active participant, as is typical for caudate amphibians, and much of his behaviour can be understood in terms of orientation to and stimulation (or persuasion) of the female. The latter is largely accomplished by the transfer of courtship pheromones from the male's mental (chin) gland. The orientation and persuasion phases of courtship appear necessary if sperm transfer by means of a spermatophore deposited upon the substratum is to be successful. The courtship of D. fuscus conanti is qualitatively identical to that of D. santeetlah, with which it is sexually compatible in the laboratory and with which it may hybridize in nature. However, a broader comparison of species in the genus Desmognathus reveals that the greatest interspecific differences occur during the orientation and persuasion phases of courtship. A complete understanding of the evolution of courtship behaviour in desmognathine salamanders awaits availability of ethograms for all other taxa and a robust, independent phytogeny for the entire subfamily.
Systematics, speciation and biogeography of the dwarf chameleons (Brookesia; Reptilia, Squamata, Chamaeleontidae) of northern Madagascar
Authors: Raxworthy C. J. , Nussbaum R. A.
Published: March 2009

Brookesia dwarf chameleons, endemic to Madagascar, were surveyed at the following localities in northern Madagascar (north of 16°S): Montagne d'Ambre, Ankarana, Manongarivo, Tsaratanana, Marojejy and Masoala. A total of 15 species occur in this region. Six new species are described and five new synonyms are identified. The genus Brookesia, the most speciose chamaeleontid genus in Madagascar, contains 23 species.

Almost all the northern Brookesia species are restricted to rainforest and occupy a relatively narrow elevational range. Although the northern rainforests represent just one‐third of the total rainforest and about 5% of the total island area, 65% of the Brookesia species occur in this region, and 52% are endemic to the northern rainforest. Five new biogeographic regions of the northern rainforest are identified based on centres of Brookesia endemicity: Montagne d'Ambre, Northwest, Tsaratanana, Northeast and East. Speciation is thought to have been facilitated in the north through geographic isolation, with the Tsaratanana mountain range and the dry forests south of Montagne d'Ambre forming barriers to dispersal, and the Tsaratanana mountains acting as a centre of isolation. The fragmented distribution of several Brookesia species of low altitude rainforest suggests a period in Madagascar's history when the climate was wetter and low altitude rainforest much more widespread.
Pre‐ and post‐maturation survival in adults of the damselfly Pyrrhosoma nymphula (Zygoptera: Coenagrionidae)
Authors: Bennett S. , Mill P. J.
Published: March 2009

The technique of mark‐release‐recapture was used to study survival before and after sexual maturity in adults of the damselfly Pyrrhosoma nymphula (Sulzer). Fewer females were recaptured upon return to water to breed despite no differences in dispersal or daily survival rate between the sexes over the immature period. Because females took longer to mature than males, their poorer recapture rate was attributed to greater overall mortality during their longer maturation phase. Survivorship curves for tenerals marked at emergence suggested that overall survival of immature adults was similar to, if not better than, that of mature adults. The reasons for this are discussed.

Jolly's model was used to estimate daily survival rates for mature adults. The assumptions of the model were tested rigorously. Estimates for females were statistically less reliable than those for males. Mean reproductive spans for males and females were 6.8 and 6.6 days, respectively, giving mean total adult lifespans of 19.4 days and 21.6 days for individuals surviving the maturation period.

Because neither sex visited the breeding site every day, sampling exclusively at water resulted in underestimation of mean reproductive spans for both sexes. Female reproductive spans were underestimated to a greater extent; because females remain away from water longer between visits, there is a greater chance that they will die before being recaptured.

Mean reproductive spans were also underestimated when only a sub‐section of the habitat was sampled. Females were significantly more mobile than males and this increased the likelihood that they would move out of the study area, resulting in more severe underestimation. The importance of obtaining accurate estimates of mature lifespan for females is discussed.
Variation in jump force production within an instar of the grasshopper Schistocerca americana
Authors: Queathem E. J. , Full R. J.
Published: March 2009

Jumping ability varies by two‐fold within an instar during the moult cycle in the grasshopper, Schistocerca americana (Acrididae: Cyrtacanthacridinae). Changes in jump distance could result from deviations in jump angle away from the optimum during development, a change in jump energy and/or a change in body mass. Body mass has already been shown to vary by over two‐ fold within an instar (Queathem, 1991). In the present study, jump angle remained near the optimum of 43° during the time course of maximal jumps throughout the instar. Jump energy was correlated with ground reaction force production because energy lost to backward rotation and drag was small. Ground reaction force production varied by nearly four‐fold over the period of the instar. Within instar six, force production and body mass accounted for 85% of the variation in jump distance. Their patterns of change relative to one another explain the four functional stages we define for within instar performance. Jump distance increased early within instar six (Stage I, days 0–2) because force production increased. In Stage II (days 3–8), jump distance remained at its peak because an increase in body mass was offset by an equal increase in force production. Jump distance decreased in Stage III (days 8–11) because body mass continued to increase while force production levelled off. Force production decreased to a greater extent than body mass during Stage IV (days 11–13), resulting in a further decline in jump distance during the three days preceding the moult to adulthood. Our results suggest that further examination of the musculo‐skeletal system could provide a causal explanation for this change in jumping ability within an instar. The present study illustrates the remarkable physiological and mechanical changes that affect locomotion within a single instar, and highlights developmental differences between arthropods and vertebrates. Arthropod development is by its very nature a discontinuous process separated by periods of continuous, parabolic changes, and this pattern of growth is reflected in locomotor performance through ontogeny.
Activity patterns of the serotine bat (Eptesicus serotinus) at a roost in southern England
Authors: Catto C. M. C. , Racey P. A. , Stephenson P. J.
Published: March 2009

Activity patterns and emergence times of a colony of serotine bats, Eptesicus serotinus, were studied in southern England. Time of emergence from the day roost varied over the summer but was strongly correlated with sunset. Mean emergence time was 11.6 ± 7.7 min after sunset. Early in summer, activity patterns were unimodal, becoming bimodal during mid‐ to late pregnancy and multimodal in early to mid‐lactation. When juveniles were volant, activity patterns became unimodal again. Periods of low ambient temperature were associated with reduced activity. The duration of the first foraging flight decreased as pregnancy progressed, possibly as a result of the greater wing‐loading caused by increased body mass. However, the first foraging flight increased in duration during the course of lactation, probably in response to a combination of increased night length and the increased energetic demands of milk production. It is concluded that seasonal variation in the length of time spent away from the roost in the serotine is related to reproductive status, night length and ambient temperature. It is suggested that the more northerly distribution of this bat in continental Europe may be due to differences in habitat use and diet.
The effects of sex, season and habitat availability on patterns of habitat use by fallow deer (Dama dama)
Authors: Thirgood S. J.
Published: March 2009

Diurnal habitat use by fallow deer Dama dama was studied between 1986–9 by direct observations from transects of eight populations in sites of differing environmental structure and composition. Sites chosen differed in the overall proportion of woodland cover, and ranged from virtually continuous woodland areas in the New Forest, southern England, to open agricultural sites with only scattered woodland copses.

Within both New Forest and agricultural areas, individuals in male groups and female groups showed similar patterns of habitat use. In the New Forest, the habitat used most overall by both sexes was open woodland, with extensive use also made of grassland, woodland clearings and closed woodland. In agricultural areas, most extensive use was made of closed woodland, with open woodland, arable land and grassland used to a lesser extent. Individuals in mixed‐sex groups in the New Forest but not in agricultural areas made more extensive use of grasslands than those in single‐sex groups.

Individuals in female groups in the New Forest showed pronounced seasonal variation in habitat use with utilization of open woodland higher in autumn and winter and grassland higher in spring and summer. Individuals in female groups in agricultural areas showed little seasonal variation in habitat use. There were insufficient data to investigate seasonal variation in habitat use by individuals in male and mixed‐sex groups.

Availability of habitat types varied widely between study sites. Use of either open or closed woodland remained high in each site reflecting increased selection for woodland resources when they were of limited availability. Fallow deer appeared able to satisfy their ecological and behavioural requirements from a variety of environments through: (i) changing strength of selection of particular habitats to compensate for differing availability; and (ii) substitution of one habitat in one area for a different habitat in another area which offered the same effective resources. This flexibility in resource use parallels observed plasticity in other aspects of fallow behavioural ecology.
Some British species of Schizomavella (Bryozoa: Cheilostomatida)
Authors: Hayward P. J. , Thorpe J. P.
Published: March 2009

Six British species of the Cheilostomatous bryozoan genus Schizomavella Canu & Bassler, 1917 are described and figured. Neotype specimens are selected for S. auriculata (Hassall) and S. linearis (Hassall), and lectotypes are selected for S. cuspidata (Hincks) and 5. hastata (Hincks). S. hastiformis Hayward and Ryland is placed in synonymy with S. linearis. S. sarniensissp. nov. is described from several south‐west British localities.
Genital morphology and copulatory mechanics in Anyphaena accentuata (Anyphaenidae) and Clubiona pallidula (Clubionidae: Araneae)
Authors: Huber Bernhard A.
Published: March 2009

The spiders Anyphaena accentuata (Walckenaer, 1802) and Clubiona pallidula (Clerck, 1757) are investigated with respect to the functional morphology of their genital organs. Copulatory mechanics is directly analysed by freeze‐fixation of copulating pairs and subsequent preparation of serial sections of the clasped genitalia. Data on courtship behaviour are included. Beyond the discussion of specific findings, the general usefulness of copulatory mechanics for phylogenetic research and the supposed function of male genitalia as stimulators are addressed.
Behaviour of female and pup grey seals Halichoerus grypus during the breeding period at Froan, Norway
Authors: SMISETH P. T. , LORENTSEN S.‐H.
Published: March 2009

We studied the behaviour of grey seals, Halichoerus grypus, during the breeding period at Froan, Norway, and compared our findings with existing studies on grey seals at breeding sites in Britain and Canada. The pups at Froan spent more time in water than pups at other breeding sites. While on‐shore, the pups at Froan spent most of their time resting, behaviour similar to pups at other breeding sites. Lactating females at Froan spent most of their time in the sea, thus differing from females at most other breeding sites which spend most of their time on‐shore. While in the sea, the females at Froan spent most time diving, typically interrupted by regular periods of surface swimming.
Statural growth in known‐age African elephants (Loxodonta africana)
Authors: LEE P. C. , MOSS C. J.
Published: March 2009

The shoulder heights of 224 females and 170 males, and hindfoot length of 236 female and 217 male known‐age African elephants (Loxodonta africana) were measured, and growth curves constructed for each measure of size. A linear relationship between foot length and shoulder height was confirmed in simultaneous measures of 97 males and 110 females. Growth curves demonstrated the typical sexual dimorphism in both foot length and shoulder height, with males growing more rapidly than females from birth onwards. The size dimorphism in foot length and shoulder height becomes marked by the age of 10 years, with males on average being 60–70 cm taller than females at 65 years. This size dimorphism is produced through faster growth which continues for longer than does that of females. The variance in growth rates is slightly greater for females than for males. It is proposed that female growth after puberty is affected by a trade‐off between growth and reproduction, while males who deviate markedly from typical patterns of growth may be subject either to mortality or energetic constraints limiting their potential variance.
Temporal activity patterns of crested porcupines Hystrix cristata
Authors: CORSINI M. T. , LOVARI S. , SONNINO S.
Published: March 2009

The activity of radiotagged adult crested porcupines Hystrix cristata L., 1758, was studied in a rural hilly area of Central Italy, from July 1990 to June 1991. Three males and one female were monitored every 15 minutes for 18–24 hours/individual/week, and their activity patterns were correlated to ambient temperature, precipitation and lunar phases. Three individuals, out of the four monitored, showed a fall of activity in the beginning of the cold season, but generally porcupines appeared adapted to a wide spectrum of temperatures. The mean duration of nocturnal and crepuscular activity was 9 h 22'±42', showing little variation throughout the year. In the cold months, i.e. when nights are relatively longer, porcupines usually left their burrows after sunset and came back some hours before sunrise. In the warm season they left their burrows at sunset, or shortly before, and returned at sunrise, or shortly after. Overall diurnal activity was scarce (2 h 11' ± 1 h 30'), but in spring it increased to over 40% of the diel activity (3 h 22' ± 3 h). Moonlight avoidance was slight. Precipitation did not seem to influence the activity of porcupines.
A nomenclature for the radula of the Cephalopoda (Mollusca)–living and fossil
Authors: NIXON MARION
Published: March 2009

A nomenclature for the teeth of the radula of fossil and living Cephalopoda is proposed. The names suggested can be used for the 13 elements (teeth and plates) across each transverse row of the radula of Nautiloidea (fossil and extant), and, by retaining the names for all except the two outer elements on either side, for the nine elements in Ammonoidea (fossil) and Coleoidea (fossil and extant). One transverse row of the radula has a central rhachidian tooth, and on either side lateral tooth 1, lateral tooth 2, marginal tooth 1, marginal plate 1, marginal tooth 2, marginal plate 2, the last two being present only in the Nautiloidea.
Cues for web invasion and aggressive mimicry signalling in Portia (Araneae, Salticidae)
Authors: JACKSON ROBERT R.
Published: March 2009

Portia is a web‐invading araneophagic spider that uses aggressive mimicry to deceive its prey. The present paper is a first step toward clarifying experimentally the cues that govern Portia's decisions of whether to enter a web, whether to make signals once in a web, and whether to persist at signalling once started. The following conclusions are supported: cues from seeing a web elicit web entry, but volatile chemical cues from webs of prey spiders are not important; seeing a spider in a web increases Portia's inclination to enter the web; after web entry, cues from webs of prey spiders are sufficient to elicit signalling behaviour, even in the absence of other cues coming directly from the prey spider; seeing a prey spider or detecting vibrations on the web make Portia more prone to signal, but volatile chemical cues from prey spiders are not important; once Portia is on a web and signalling, seeing a moving spider and detecting vibrations on the web encourage Portia to persist in signalling; on the basis of visual cues alone, Portia can distinguish between quiescent spiders, insects and eggsacs.
Effects of foliaceous varices on the mechanical properties of Chicoreus dilectus (Gastropoda: Muricidae)
Authors: MILLER D. J. , LABARBERA M.
Published: March 2009

Removal of the foliaceous varices from the shells of Chicoreus dilectus had no significant effect on the crushing strength (load at failure) of the shells, but decreased the total work necessary to break the shells by 35–50%. This effect was due to the removal of varices as an architectural feature of the shell rather than simply to the removal of shell material per se; varicate shells had a mean work to failure per unit shell mass 1–6–2–3 times greater than avaricate shells. Because the strength of gastropod shells often exceeds the maximum forces that durophagous predators may bring to bear on them, work to failure may be a more important factor in the design of gastropod shells than breaking load.
Scaling relationships within the maxillary tooth row of the Felidae, and the absence of the second upper premolar in Lynx
Authors: RUSSELL A. P. , BRYANT H. N. , POWELL G. L. , LAROIYA R.
Published: March 2009

Suggestions that short‐faced members of the Felidae tend to lack the second upper premolar (P2) imply a possible shift in scaling associated with the palate and maxillary tooth row in Lynx, which lacks P2, as compared to felids that retain it. This hypothesis is tested using a scaling model that relates the lengths of the palate, and the upper tooth row and its components, to post‐palatal skull length in the small to moderately large felids Felis catus (domestic cat), L. canadensis (Canada lynx), F. pardalis (ocelot), and F. concolor (cougar). Scaling relationships of both palate and tooth row length to post‐palatal skull length do not differ significantly from isometry in all four species. However, ocelots have a significantly shorter palate and tooth row than lynxes over their overlapping ranges of post‐palatal skull length, suggesting that the absence of P2 is not correlated with the length of the face in these species. CI, P3 and P4 tend to be relatively longer in larger felids; none the less, ocelots have a relatively small P3 and lynxes have a proportionately large P4. Because both lynxes and ocelots have a relatively small gap between CI and P3, the absence of P2 is not correlated with available space within the tooth row in adults. However, lynxes also appear to have a relatively long dP3 that almost obliterates the diastema within the deciduous tooth row. The absence of P2 in Lynx may be an engineering artefact that is associated with a shift in proportions within the deciduous toothrow, resulting in inhibition of the development of P2 and dP2 early in ontogeny. Despite the variable occurrence and polymorphism associated with P2 in the Felidae, this character has systematic value within this clade and is a synapomorphy for Lynx.
The influence of increasing density on body weight, kid production, home range and winter grouping in roe deer (Capreolus capreolus)
Authors: Vincent J. P. , Bideau E. , Hewison A. J. M. , Angibault J. M.
Published: March 2009

In this paper, we present an analysis of the consequences of increasing density, over a period of nine years (from 1980 to 1988), on the dynamics, and the social and spatial organization of a forest roe deer population. Hunting of this population ceased in 1979, after which time there was a significant increase in population density, with three distinct periods easily identified: 1980–1983 (PI), immediately following cessation of hunting, characterized by a relatively low density (d = 5–7 animals/100 ha), 1984–1985 (P2), a period of rapid population growth, and 1986–88 (P3), a period of high density (d = 25 animals/100 ha). During PI, the population was irregularly distributed across the study site but, as density increased, distribution became more uniform, and eventually covered the whole of the available area. Home‐range structure and shape remained unchanged from PI to P3 but, by the end of the study, average range size was 30% lower for adult males only, and the period prior to subadult males, but not females, establishing a permanent home range had increased from c. 18 month to c. 30 months. Winter group size increased overall from PI to P3 with, for the first time, observations of groups of five or more animals and a reduction in the frequency of observations of solitary females, with does more commonly observed in pairs or small groups; the proportion of solitary males, however, did not change between the two periods. The mean number of kids per female declined significantly from PI to P3 and body weights recorded for juveniles of both sexes and for adult males were also significantly lower during the period of relatively high density (P3). However, for adult females, absolutely no body weight change was observed. This divergence between the sexes of response to increasing density is discussed.
Selection for an unstable micropterism inPyrrhocoris apterus(Heteroptera: Pyrrhocoridae)
Authors: Socha Radomír
Published: March 2009

Twenty‐eight generations of mass selection for an unstable micropterism (short wings) in the red firebug,Pyrrhocoris apterus(L.), resulted in anunstable micropterous(ump) strain with a high frequency of micropterous individuals. The strain, segregating individuals with enormously reduced wings, is polymorphic for mosaic pigmentation in the epidermis. Micropterous individuals, both symmetric and asymmetric, appear predominantly among pigmentation mosaic (umpmo) forms. Individuals with a normal, nonmosaic epidermis (umpwt) are rarely micropterous. The reproductive capacity of micropterousumpmofemales is strongly reduced. It is suggested that pigmentation mosaicism and unstable micropterism may have a common or linked genetic basis. A new mode of wing length regulation is suggested, engaged in conspicuous destabilization ofumpwings and consisting presumably of transpositions of mobile genetic elements.
The biology, life cycle and ecophysiology of the Antarctic miteAlaskozetes antarcticus
Authors: Block W. , Convey P.
Published: March 2009

This paper is dedicated to the late Nigel Bonner, who as Head of the Life Sciences Division at British Antarctic Survey, encouraged and supported this research with his characteristic enthusiasm.

The cryptostigmatid miteAlaskozetes antarcticus(Michael) is a dominant member of many terrestrial communities in the maritime Antarctic, where it survives extreme temperatures, short cold summers, numerous freeze‐thaw cycles, desiccating conditions and a limited season for growth and reproduction. However, examination of features of its biology, from morphology, through life‐history strategy to physiology, indicate very little specialization to the Antarctic environment.Alaskozetes antarcticusis a herbivore/detritivore, typical of the Cryptostigmata in general, with low feeding and growth rates, long life span and low reproductive output. Physiological specializations exist in the form of low enzyme activation energies and elevated metabolic rates at low temperatures when compared with temperate species, and associated low optimum temperatures for activity, feeding and growth. Growth rates comparable with temperate species are achieved in the field, with an extended life cycle of five years or more as a result of the short growing season, and the ability of all life stages to overwinter equally successfully. Overwintering survival, involving supercooling enhanced by the use of antifreezes such as glycerol, although initially described in Antarctic species, is now known to be characteristic of many temperate relatives, so it is not a specific adaptation to the polar environment. The obvious success ofA. antarcticusin maritime Antarctic terrestrial environments must be attributed to a combination of several features characteristic of the Cryptostigmata in general, rather than to specific polar adaptations.
Life histories, secondary production and microdistribution of Psephenidae (Coleoptera: Insecta) in a tropical forest stream
Authors: Dudgeon David
Published: March 2009

The ecology of four species of Psephenidae (water penny beetles) was investigated in Tai Po Kau Forest Stream (TPKFS), New Territories, Hong Kong, over a two‐year period. Quantitative benthic samples were taken from different microhabitats in the stream on 47 occasions and, in combination with light‐trap catches of adult beetles, were used as a basis for investigating life‐history patterns and estimating secondary production. Total psephenid annual production over the period 1977–79 was 930–5 mg AFDW (ash‐free dry weight) 0.5 m‐2, but was more than twice as high in 1977–78 (1381–6mg AFDW 0.5m‐2) than in 1978–79 (562.6mg AFDW 0.5m‐2). Sinopsephenus chinensis and Eubrianax sp. were the most abundant psephenids in TPKFS, but the larger S. chinensis contributed most to total psephenid secondary production. Eubrianax sp. made the second largest contribution to production, while the contribution of the two remaining species (Psephenoides sp. and Mataeopsephus sp.) was minor. Eubrianax sp. production was generally constant between years, but production (and population densities) of the other three psephenids declined in 1978–79. Sinopsephenus chinensis was clearly bivoltine in TPKFS, but Eubrianax sp. and Psephenoides sp. showed asynchronous growth and almost continuous recruitment. Accurate estimates of production: biomass ratio (P: B) ratio were possible for S. chinensis only, and varied between 12.8 and 19.4 over the two years of the study.

Eubrianax sp. and (especially) S. chinensis were most abundant in midstream microhabitats but Psephenoides sp. was more numerous close to the stream banks. Mataeopsephus sp. was relatively rare and lacked an obvious microdistribution pattern. Multivariate statistics (principal components analysis followed by multiple regression) were used to investigate the relationship between psephenid densities in each benthic sample and the sediment characteristics, detrital standing stocks and algal biomass in the environment where the sample was taken. The analysis revealed that psephenid microdistribution was influenced by sediment grain‐size characteristics rather than by algae or detritus, but the proportion of variation in the abundance of psephenid species accounted for by sediment characteristics was rather low.
Thermoregulation and metabolism in the Cape golden mole (Insectivora: Chrysochloris asiatica)
Authors: Bennett N. C. , Spinks A. C.
Published: March 2009

The Cape golden mole, Chrysochloris asiatica is an insectivore which excavates superficial foraging burrows as it searches for its food. It has a mean (±S.D.) resting metabolic rate (RMR) when newly captured of 1–17±0.17 cm3 O2g‐1 h‐1 (n= 14), within the thermoneutral zone (TNZ) of 30–32°C.

The body temperature (Tb) of the mole in the TNZ is low 32.9 ± 0.36 (n= 14) and remains stable at ambient temperatures (Tas) from 28–32°C. Above 32°C (range 34–37°C), Tb increases albeit slightly to 36 ± 1.75°C (n= 14). The conductance is high 0.27 ± 006cm3 O2g‐1 h‐l°C‐1 (n= 46) at the lower limit of thermoneutrality. The mean RMR at 9°C (the lowest Ta tested) was 4.82±11 cm3 O2g‐1h‐1, which is 4.1 times that of the RMR in the TNZ.

At an ambient temperature of 9°C, three of the golden moles entered a state of torpor where the RMR was reduced from 5.9±0.56 to 10 1.0 ± 0.69cm3O2g‐1h‐1.
Mass transfer during lactation of an ice‐breeding pinniped, the grey seal (Halichoerus grypus), in Nova Scotia, Canada
Authors: Baker S. R. , Barrette C. , Hammill M. O.
Published: March 2009

Mass transfer during lactation was examined by serial weighing of mother‐pup pairs in an ice‐breeding population of grey seals, in the southern Gulf of St. Lawrence (c. 46° N‐c. 63° W), Canada.

Male pups (171 ± 1–3kg, n= 4) were significantly heavier at birth (P= 001) than females (14.6 ± 1.4 kg, n= 9), and grew significantly faster until weaning (males: 2.7 ± 0.6kg/d, n= 45; females: 2.4 ± 0–5kg/d, n= 63, P= 004). At weaning, males (56.2 ± 6.7 kg, n= 24) were significantly heavier (P= 0‐01) than females (51.6 ± 53kg, n= 25). Lactation for both sexes lasted 14.9 ± 1.4 days (n= 13).

At parturition, adult females weighed 227 ± 26 kg (n= 26). During lactation they lost 5.6 ± 1.lkg/d (n= 35). An analysis of carcass composition of six females collected during different stages of lactation showed that they utilized 61% of their fat reserves during lactation.

Efficiency of mass transfer varied from 25–3% to 70–4% (49.3 ± 10.8%, n= 35). Examination of stomach contents indicated that some ice‐breeding females consumed food during lactation.

Our results in this ice‐breeding population show that females invest more in sons than in daughters.
Movements and habitat use in gravid and nongravid female garter snakes (Colubridae: Thamnophis)
Authors: Charland M. Brent , Gregory P. T.
Published: March 2009

We examined movements and habitat use with respect to reproductive condition for female garter snakes (Thamnophis sirtalis and T. elegans) in south‐eastern British Columbia, Canada. Radiotelemetry was used to measure movements by snakes and the locations of animals were used as habitat sampling points to examine patterns of habitat use. Rates of movement of gravid females were low during gestation, but increased following parturition until they were similar to those of nongravid females. Both groups used areas characterized by high levels of cover (vegetation, rocks, or trees), but there were marked differences in the habitat features of the sites selected. Gravid females remained primarily in rocky areas that were relatively rare on the study site. In contrast, nongravid females used a variety of habitats, ranging from grasslands to forests, but preferred areas with relatively high amounts of overhead cover. Our results indicate that predator avoidance may be a primary feature of habitat choice for both groups. However, gravid females appear to have an additional requirement for careful thermoregulation, and may be selecting sites that balance both needs.