bluuebunny/crossref_metadata_2025 huggingface dataset:
The testicular cycle and androgen biosynthesis in the tree sparrow Passer montanus saturatus
Authors: Chan K. M. B. , Lofts B.
Published: August 2009

The annual testicular cycle of the tree sparrow (Passer montanus saturatus) has been studied by histochemical and biochemical techniques.

The spermatogenetic cycle has two clearly defined peaks of activity. Throughout the winter the gonads are sexually regressed, but a recrudescence of spermatogenetic activity begins in the spring and the gonads rapidly develop into full breeding condition by April. In late April and early May a rapid testicular regression takes place as spermatogenetic activity terminates. Then, in July, a second seasonal spermatogenetic wave begins and gonads once again develop into a breeding condition. By August the testes have become fully regressed into their sexually quiescent post‐nuptial phase and remain this way until the following spring. The seasonal rehabilitation of the interstitial tissue, which is a characteristic part of many avian cycles, does not occur until this latter regressive phase.

The seasonal fluctuations in the in vitro production of testosterone from A5‐pregnenolone‐16T shows the same annual bimodal pattern as the spermatogenetic cycle, being high at times when the seminiferous tubules are spermatogenetically active, and low during times of sexual quiescence. There is a close correlation between the level of testicular androgen synthesis and the seasonal fluctuations in the interstitial cell lipid cycle. Thus, testosterone synthesis builds up in the spring at a time when small sudanophilic lipid droplets are present in the interstitial Leydig cells, and reaches a peak at a time when this material is becoming rapidly depleted from the cell cytoplasm. During the first period of testicular regression, the Leydig cells become markedly sudanophilic, possibly as a result of the accumulation of precursor material at a time of low testosterone synthesis, then again become depleted of this material as secretory activity builds up once again.

The possible interrelationship between the histochemical and biochemical cycles, and also the spermatogenetic cycle and the daily photoperiods, are discussed.
Food and feeding habits of the frog Rana temporaria in bogland habitats in the West of Ireland
Authors: Blackith Ruth m. , Speight M. C. D.
Published: August 2009

A species list of prey organisms of Rana temporaria in a blanket bog and adjacent man‐modified (mainly grassland) habitats is presented. From this it is concluded, in line with the findings of other authors, that this species is unselective and sedentary in its feeding habits. Argument is presented suggesting these habits are ideally suited to the needs of a bog‐land predator. It is further suggested that these habits tend to make R. temporaria a particularly effective predator of ground‐living predatory and parasitic insects.
Reproduction in male Pipistrellus pipistrellus (Mammalia: Chiroptera)
Authors: Racey P. A. , Tam W. H.
Published: August 2009

The annual reproductive cycle has been investigated in the male pipistrelle bat Pipistrellus pipistrellus. Spermatogenesis occurs during summer and spermatozoa are produced in August and September. The seminiferous tubules then regress rapidly but sperm are stored throughout winter in the cauda epididymidis. Little change is apparent in the morphology of the Leydig cells throughout the year, and histochemical studies have revealed no seasonal differences in the occurrence of enzymes involved in steroidogenesis. The percentage yields of testosterone and androstenedione after incubation of testis and adrenal tissues in vitro with tritiated pregnenolone have been determined and measurements made of the concentration of these hormones in testes and whole blood. Although the highest levels of these androgens are synchronous with spermatogenesis, both continue to be produced by the testes during winter. Studies in castrated bats have confirmed these observations and indicate that the activity of the accessory reproductive organs during winter is dependent on testicular androgens. The testicular cycle of the pipistrelle is not thought to be complicated by adrenal androgenesis, or storage of androgens in the brown fat. The interrelationships between reproduction and hibernation in bats are discussed.
The sacculus epipharyngeus in the Giant panda, Ailuropoda melanoleuca
Authors: Cave A. J. E.
Published: August 2009

The bursa epipharyngea of the Giant panda,Ailuropoda melanoleuca,is a saccular diverticulum (sacculus epipharyngeus) situated between pharynx roof and basis cranii. In the Ursidae the bursa comprises a pair of unequal‐sized diverticula having separate ostial communication with the epipharynx. Such dual type of bursa was recorded by Davis (1964) in theAiluropodaspecimen he systematically anatomized and was regarded as evidence indicating affinity with the Ursidae rather than with the Procyonidae. But in four additionalAiluropodaspecimens subsequently examined, and described herein, the ursid pattern of sacculus did not obtain. The significance of this difference in the anatomical findings is indicated.
Effect of temperature on embryonic development and diapause in Chesias legatella (Lepidoptera: Geometridae)
Authors: Wall C.
Published: August 2009

The changing temperature requirements ofChesias legatellaSchiffermüller during embryonic development are investigated. The eggs are laid in the autumn and embryogenesis is interrupted by a short diapause at the germ band stage, after which development proceeds slowly throughout the winter. The effects of temperature during the pre‐diapause, diapause and post‐diapause phases of development are assessed by examination of the rate and variability of morphogenesis through all the embryonic stages. An examination is presented of the effect of temperature during the late autumn on the rate and uniformity of diapause termination, and consequently on the length of the hatching period the following spring.
Protozoan parasites of the blood of British wild birds and mammals*
Authors: Baker J. R.
Published: August 2009

The reported occurrence of protozoan parasites of the blood of British wild birds and mammals is reviewed. Nineteen species of British birds have been recorded as hosts of Haemoproteus (or Parahaemoproteus), Leucocytozoon (or Akiba), Plasmodium, Trypanosoma or “atoxoplasms” (a group whose taxonomic status is presently in doubt), and seventeen species of British mammals are known to be hosts of Babesia, Hepatozoon, Polychromophilus or Trypanosoma (including at least three species from Chiroptera: T. (Schizotrypanum) dionisii, T. (S.) vespertilionis and T. (Megatrypanum) incertum).
Some aspects of the breeding biology of the equatorial land snail Limicolaria martensiana (Achatinidae: Pulmonata)
Authors: Owiny A. M.
Published: August 2009

A study of the breeding season of the polymorphic equatorial land snailLimicolaria martensianaSmith (Achatinidae: Pulmonata) lasting six years and six months in populations in the Kampala District (lat. 0 20′) and the Equator line shows that the snail breeds continuously throughout the year but has bimodal peaks in its breeding which occurs during the dry seasons, while during the rainy seasons breeding is low. It is the decrease in the amount of rainfall which induces peak breeding and as a result there is an inverse relationship between the amount of rainfall and the breeding intensity. The evolution of ovoviviparity with the ability to retain eggs and/or youngin uteroduring aestivation is the phenomenon that enablesL. martensianato have peak breeding during the dry seasons. Moisture which enables young to feed and thus grow is an ultimate factor in determining breeding inL. martensiana. The gestation period is 10 to 14 days during the rainy seasons but the snail retains its eggs and/or youngin uteroduring the dry seasons and only deposits them when rain returns. The eggs take 18.6±5.43 days (N=130) to hatch after they are laid. Hatchingin uteroand outside occurs by the young eating the egg shells. Oogenesis in the snails occurs at all times.L. martensianastores viable allosperms which it can use for further reproduction.
Respiratory surface areas of an air‐breathing siluroid fish Saccobranchus (Heteropneustes) fossilis in relation to body size
Authors: Hughes G. M. , Singh B. R. , Guha G. , Dube S. C. , Munshi J. S. Datta
Published: August 2009

The surface area of the gills, air sacs and skin have been measured in specimens of different body size and their relationship to body weight fits the equation: area=aWb. The slopes (b) of the double logarithmic plots are 0.746 (gills), 0.662 (air sacs) and 0.684 (skin). The gills are poorly developed and their average weight specific area is less than figures obtained for sluggish marine fishes. The skin has an area about 70% of the total respiratory surfaces (gills+air sac+skin). Nevertheless the greater thickness of the skin leads to a smaller diffusing capacity of the tissue barrier (Dt) as compared with the gills and air sac. The air sac area for each ml of air that it contains is about 10.5 cm2 which is much lower than figures obtained for lungs of other air‐breathing fish and for tetrapods.
Synthetic parental calls, auditory discrimination learning and individual recognition by young precocial birds: frequency, intensity and duration
Authors: Cowan P. J.
Published: August 2009

A series of experiments were carried out to investigate the effects of training and testing with the frequency, intensity and duration of simple synthetic sounds on the approach behaviour and distress vocalization of young Domestic chickens. Familiar frequencies occurring singly and in combinations can increase the responsiveness of chicks compared with novel frequencies. Neither duration nor intensity appears involved in auditory discrimination learning per se, but rather both allow fine control over the young chick's behaviour. On the basis of comparison with the results of an experiment involving parental calls, the possible structure of a call which would facilitate individual recognition of parents by voice was suggested. Sound frequency may be the most important call parameter facilitating individual recognition of the parental voice by young precocial birds.
Experiments on resting site selection by nocturnal moths
Authors: Boardman Margaret , Askew R. R. , Cook L. M.
Published: August 2009

When different species of moths are presented with a choice between black and white resting backgrounds, there is a strong correlation between the colour selected and the reflectance of the forewings. Under more natural conditions, light‐coloured moths usually rest on fresh vegetation whilst dark‐winged species select tree bark or rest upon the ground, and different defensive strategies appear to have been adopted by species in these two latter situations. Studies on the mechanism of background selection, and on background selection in polymorphic species, are reviewed.
The effects of oestrous condition and familiarity on the sexual behaviour of polecats (Mustela putorius and M. fur × M. putorius hybrids)
Authors: Poole Trevor B.
Published: August 2009

The effects of two factors on the sexual behaviour of polecats (Mustela furo and M. putorius×M. furo hybrids) were investigated, in an indoor arena of 16 m2, firstly the oestrous condition of the female and secondly the familiarity of the two individuals.

The initial approaches of a male polecat are similar irrespective of the oestrous condition of the female but his subsequent behaviour is dependent upon the female's response. Whereas males copulated with oestrous females they showed a wider repertoire of social acts and a greater number of changes of behaviour towards females which were not in oestrous. Unreceptive females elicited both sexual and aggressive behaviour from males.

Unfamiliar females provide a more powerful eliciting stimulus for the male's copulatory behaviour than do familiar females.
Aspects of the overwintering habitat of the Wolf spider Pardosa lugubris
Authors: Edgar Walter , Loenen Maarten
Published: August 2009

Pardosa lugubris occurs in the vicinity of woodlands and overwinters among leaf litter. Field recordings of litter temperatures in winter indicate that temperatures within the litter fluctuate much less than those on the surface and that the lower the air temperature the greater the difference between the temperature of the surface litter and that of the deep litter. Specimens of P. lugubris, in a litter hill constructed in the laboratory, moved into the deeper layers of the litter as the temperature was lowered below freezing. It is suggested that the use P. lugubris makes of leaf litter as an overwintering habitat may account for its close association with woodland and its occurrence in more northerly latitudes compared with other members of the genus.
Spawn site selection and colony size of the frog (Rana temporaria) and the toad (Bufo bufo)
Authors: Cooke A. S.
Published: August 2009

Information has been collected from various sources on spawn site selection and colony size of the frog (Rana temporaria) and the toad (Bufo bufo). Details are tabulated for 764 frog breeding sites in Britain and in the Republic of Ireland and for 139 toad sites in Britain (the toad does not occur in Ireland). Both species tend to breed in whatever types of site are most available. In Britain the garden pond has steadily increased in importance for both species since 1950. Frogs usually spawned in shallow water, 266 reports out of a total of 588 (45%) referring to water up to six inches (15 cm) deep. Toads tended to spawn in deeper water, 48 reports out of 82 (59%) mentioning water 7–18 inches (18–46 cm) in depth. Median depths were: frog, seven inches (18 cm); toad 13 inches (33 cm). Information on colony size was assimilated for 574 frog colonies and 86 toad colonies. Colonies in gardens were smaller than those in other types of site. Relatively fewer large frog colonies (≡100 animals) were found to occur in London than elsewhere in Britain, and British colonies were generally larger than those in Ireland. Colonies of 100 or more individuals were recorded relatively more frequently for toads than for frogs. By combining information on choice of site and colony size, rough estimates can be derived of the percentage of frogs and toads breeding in gardens and other types of site. For instance, in the London area in the 1960s perhaps 20–25% of the frogs bred in gardens and private grounds. The ecological significance of these observations is discussed.
The blood circulatory function of the dorsal aorta ligament in Rainbow trout (Salmo gairdneri)
Authors: Priede Imants G.
Published: August 2009

An elastic longitudinal ligament stretched under considerable tension lies within the dorsal aorta of Rainbow trout.

Experiments with mechanically simulated swimming movements in an artificial model demonstrate that such a ligament can act as a pump mechanism. The output of the pump increases with tail beat frequency up to a certain point where the mechanism tends to break down. Investigations on the trout dorsal aorta show that pump breakdown probably takes place at relatively low output pressures.

Fundamental blood flow considerations indicate that a fully effective dorsal aorta pump over the full range of swimming speeds is undesirable. It is concluded that the dorsal aorta ligament can act as a pump which automatically increases circulation during swimming particularly to the body musculature. The output pressure is small but may be of significance in causing reflex increase in cardiac output.
An investigation of playful behaviour in Rattus norvegicus and Mus musculus (Mammalia)
Authors: Poole Trevor B. , Fish Jane
Published: August 2009

The playful behaviour of laboratory rats (Rattus norvegicus) was investigated in litters of five individuals with the mother present; parallel observations were made on mice (Mus musculus). Seven mixed litters containing four young rats and a young mouse fostered at birth were also observed.

Solitary play was recorded in both species and took a similar form but social play was only observed in rats. In rats, solitary play frequently preceeded social play.

The behavioural elements involved in the social play of Rattus norvegicus were described, and the majority of these were the playful equivalent of adult agonistic behaviour elements. These social play elements were found to be organized into definite sequences which differed from those of adult aggression. Each behavioural element was found to act as a social releaser.

Young mice did not respond playfully to social play from a rat litter mate; mice were less attractive to rats as playmates in comparison with fellow rats.
The genus Xenoclarias (Pisces, Siluriformes) in Lake Victoria, with a redescription of Xenoclarias eupogon and notes on the biology of the species
Authors: Gee J. M.
Published: August 2009

The acquisition of large collections of the catfish Xenoclarias Greenwood from Lake Victoria, East Africa, demonstrated a need for a reappraisal of the taxonomy of the genus. It is suggested that only one species, Xenoclarias eupogon (Norman) is found in the lake but that it is very variable in many of its morphometric characters. The species is redescribed from data obtained for 72 fishes from various localities and depths in the lake. Observations of the food of the fish show it to be almost entirely insectivorous with a preference for Chironomidae over Chaoboridae larvae. Evidence is also put forward to support the view that X. eupogon breeds on or close to rocky shores.
The diet of feral Herpestes auropunctatus (Carnivora: Viverridae) in the Fijian Islands
Authors: Gorman Martyn L.
Published: August 2009

On the basis of scat analysis, the diet of the mongoose Herpestes auropunctatus is described for animals living in a variety of habitats on Viti Levu, Fiji. The species eats a wide variety of vertebrate, invertebrate and plant food. Although introduced to Fiji in an attempt to control rodents, the mongoose has had little success in this respect. However, as a result of predation it may have had an adverse effect on various members of the native fauna.
Observations on the use of grottos by Mediterranean Monk seals (Monachus monachus)
Authors: Bareham J. R. , Furreddu A.
Published: August 2009

A group of six Monk seals (Monachus monachus) was discovered to lie up inside a grotto on the shores of a lake reached via an underwater passage. Nearly 1200 hours of observation on the movement of the seals showed that the greatest use of the grotto was made during the winter months and when the wind was towards the grotto entrance. Entry and exit times were not significantly affected by sea state, dark or light, nor were they significantly correlated with sunrise and sunset times or sea and air temperature. These variables did not significantly affect the length of stay in the grotto. Entry occurred most frequently in the early morning and exist at night.

Discussion is given of the possible reasons why grottos are used by Monk seals. This appears to be a recent adaptation which may be related to the effects of human disturbance.
Patterns of social grouping in ungulates of Tsavo National Park, Kenya
Authors: Leuthold Walter , Leuthold Barbara M.
Published: August 2009

The paper presents data on group size frequencies and mean group sizes in 11 species of ungulates and, for seven of them, more detailed information on the composition of groups in Tsavo East National Park, Kenya. In several species, mean group size was higher in a part of the study area with more open vegetation. No significant seasonal variations in mean group size were found, except in waterbuck which concentrated markedly in one location during the dry season. Minor local or seasonal variations in the proportions and/or sizes of different group types were evident in most species. In general, grouping patterns were consistent with the type of social organization found in other areas for the species concerned. Frequencies and types of interspecific associations, and the possible factors underlying their formation, are also discussed.
Studies on the chemical ecology of Biomphalaria glabrata: The effects of chemical conditioning by the snails kept at various densities on their growth and metabolism
Authors: Thomas J. D. , Goldsworthy G. J. , Benjamin M.
Published: August 2009

It has been shown that heterotypically conditioned media (Het. C.M.) produced by lettuce fed snails maintained at various densities can influence the allometric growth and the rates of specific growth, ingestion, egestion, assimilation and heart beat of isolated assay snails. The growth rate of the assay snails was enhanced by increasing the density of snails producing the Het. C.M. to an optimum threshold of one snail per 100 ml. Further increases in density were followed by a decline in their growth rate. The higher growth achieved by the assay snails in the optimum treatment can be attributed to the fact that their specific growth rates over the first three weeks of the experiment were higher than those of snails in other treatments.

Ingestion and assimilation correlated well with specific growth rates. Percentage assimilation values are high, ranging from 78.4 to 89.6%. The onset of reproductive activity is followed by a dramatic decline from approximately 26 % to 5 % in the gross efficiency of utilization of food for somatic growth.

Snails not receiving Het. C.M. from the outer tanks have a relatively higher ratio of specific growth rate in weight to length than was the case with snails in the other treatments. The heart beat rates of snails in the Het. C.M. produced by snails at densities of 80 to 160 snails per 41 are significantly lower than those of snails at other densities. The possible causation and adaptive significance of these effects are discussed.
Excirolana braziliensis, a Pan‐American sand beach isopod: taxonomic status, zonation and distribution
Authors: Glynn Peter W. , Dexter Deborah M. , Bowman Thomas E.
Published: August 2009

Excirolana braziliensis Richardson is shown to be the senior synonym of Cirolana salvadorensis Schuster and C. koepckei Bott. The latter two species, incorrectly assigned to Cirolana, were formerly regarded as distinct and were separated on the basis of size‐dependent characters. Sampling of sandy beaches along the eastern Pacific from Mexico to Chile (21 localities) and the western Atlantic from Mexico to Brazil, including the West Indies (20 localities), demonstrates that E. braziliensis is commonly the most abundant macroscopic organism present in this habitat. Marked differences in zonation of young and adults are illustrated from data in Panama.
On the ecology of Crataerina hirundinis (Diptera: Hippoboscidae) in Scotland
Authors: Summers R. W.
Published: August 2009

During the summer of 1969, in eastern Scotland, a study was carried out on Crataerina hirundinis (L.), a flightless ectopasasite of the House martin. The environment of the hosts's nest was described. The fly was found to move actively between the nests of its host. The populations in the main study colonies (in farm cart‐sheds) were higher than in colonies on the eaves of buildings or on a cliff. Juvenile House martins were more heavily infested than the adults. Female flies predominated in the nest populations and were also found to be proportionately more common on the birds than in the nests. Feeding studies showed that female flies imbibed 4.8 mg of blood per day whereas males took 3.5 mg. Although C. hirundinis is specific to the House martin, it can also breed successfully on the Sand martin and Swallow. Ecological factors are believed to prevent these birds from being regular hosts. House sparrows cannot act as hosts.
Cells secreting non‐resinous substances in the female lac insect Kerria lacca (Homoptera‐Coccoidea)
Authors: Haque M. S.
Published: August 2009

The non‐resinous secretions, both waxy and non‐waxy, are all produced by specialized epidermal cells.
Fishes of the family Pseudochromidae (Perciformes) in the northwest Indian Ocean and Red Sea
Authors: Lubbock Roger
Published: August 2009

An account is given of pseudochromid fishes from the northwest Indian Ocean and Red Sea. Thirteen species are recorded; four new species of Pseudochromis and two new species of Chlidichthys (all from the Red Sea) are described. Keys are provided, and details are given of the ecology, maintenance in aquaria, and spawning of pseudochromids. As an appendix, a new name is proposed for Pseudochromis punctatus Kotthaus, 1970.
Components and patterns in the behaviour of the nematode Caenorhabditis elegans
Authors: CROLL NEIL A.
Published: August 2009

The behavioural activities during movement, feeding and defaecation have been recorded and measured in adult females of Caenorhabditis elegans. The postures and components of recognizable wave forms are described. Stress has been laid on the mechanism of antagonistic interaction of backward and forward movement, and the rates and characteristics of “spontaneous” and “induced” reversal periods. During feeding, rapid rates of pharyngeal activity are invariably related to low rates of somatic muscle wave propagation. Head oscillations are considered to be separate events not directly linked with feeding or foraging. The combination of certain wave forms, together with other measurements have been used to develop a hypothesis to describe a co‐ordinating mechanism applicable to the nematode level of organization.
Behaviour of the Talapoin monkey (Miopithecus talapoin) studied in groups, in the laboratory
Authors: DIXSON A. F. , SCRUTON DIANE M. , HERBERT J.
Published: August 2009

The behaviour of the Talapoin monkey has been studied both qualitatively and quantitatively by observing small captive groups kept in the laboratory. The behavioural repertoire is compared with that of other Old World Catarrhines. Talapoins show greater similarities to Cercopithecus monkeys than to Erythrocebus, Macaca, Papio or Cercocebus. However, there are differences in behaviour between talapoins and Cercopithecus monkeys, which lend additional support to the view that the former should be placed in the separate genus Miopithecus.
The feral goats of Kielderhead Moor
Authors: MCDOUGALL PETER
Published: August 2009

Herds of feral goats are present along the high ground of the Scottish Borders at the College, Hindhope, Kielderhead Moor (the study area), Bewcastle Fell and Roan Fell.

In the study area the nannies remained solitary, or in the company of their yearlings on the steep ground below the high moor throughout the winter. After the birth of their kids in March two female herds were formed each with a herd billy which came from the two male herds which were present through the winter on the high moor. The male herds left the study area in the spring and their ranges are not known. The two female herds maintained separate ranges on the high moor until the end of August when they combined into one large herd and were joined by a strange herd of billies which had not previously been seen.

After the first three or four days of its life the kid is left in a hiding place for most of the day whilst its mother ranges widely grazing with the herd. The kids join the herd when they are about six weeks old.

The Kielderhead Moor goats had a recruitment rate of 0–29/nanny/year and the females have a further expectation of life of 3–7 years. Figures for the billies are unreliable as disappearances of males from the moor are more likely to be the result of emigration than of deaths. While the herds of nannies have fairly restricted home ranges there is some evidence to suggest that many of the billies wander freely along the Borders.

In the early part of the summer the sheep and goats are eating very similar proportions of the plants present on the moor. Later on in the season there is a divergence with the sheep eating less Calluna while the goats eat less Eriophorum, but as the Trichophorum becomes available both animals include this in their diet.
The reproductive cycle, condition and feeding in Barbus liberiensis, a tropical stream‐dwelling cyprinid
Authors: PAYNE A. I.
Published: August 2009

This investigation examines the biology of Barbus liberiensis, a small cyprinid living in the forest streams of Sierra Leone and Liberia, in relation to seasonal changes in the environment. The population studied showed a single discrete breeding season coinciding with the early part of the rains. Maturing fish previously marked moved upstream at this time. The pattern of gonad development is analysed and the relationship of fecundity to body size is defined numerically. The total and somatic (i.e. excluding gonad weights) condition of the fishes, relative to the length/weight data in September‐November when the gonads are resting, reach a peak at spawning time for both mature males and females and for immature fish. The pattern of condition during a year differs in the two sexes.

B. liberiensis consumes a wide variety of foods but relies largely on insects and higher plant fragments. Debris from the forest canopy is an important source of nutriment. The fish feed, during the daytime and possibly at night, throughout the year. Experiments to determine the rate at which food passes through the gut are described and show that food passage is rapid.

The seasonal cycles in condition and reproduction are discussed in relation to cycles in some other tropical and temperate riverine fishes.
The feeding and ranging behaviour of Galapagos giant tortoises (Geochehne elephantopus) The Cambridge and London University Galapagos Expeditions, 1972 and 1973
Authors: RODHOUSE P. , BARLING R. W. A. , CLARK W. I. C. , KINMONTH ANN‐LOUISE , MARK ELIZABETH M. , ROBERTS D. , ARMITAGE LESLEY E. , AUSTIN P. R. , BALDWIN S. P. , BELLAIRS A. D. , NIGHTINGALE P. J.
Published: August 2009

Field observations on the behaviour of adult Galapagos giant tortoises (Geochehne elephantopus) on the islands of Santa Cruz (Indefatigable) and Pinzon (Duncan) were made by the 1972 Expedition, and on Santa Cruz by the 1973 Expedition. The animals (in all 14 on Santa Cruz and three on Pinzon) were observed continuously throughout the day for periods of 3–14 days so that their main non‐reproductive activities (feeding and walking) could be quantitatively recorded. The period of potential activity was between about 08.00 hrs and 16.00–18.00 hrs, but the pattern of behaviour was extremely variable, both in a given individual and between one individual and another; it seemed little influenced by the relatively slight fluctuations of temperature and climate which occurred during the period of study (July‐September) on Santa Cruz. The tortoises on Pinzon, a much more arid island, were less active, and one showed a strongly bimodal activity pattern with a resting period during the middle of the day. The animals studied in 1972 showed a strong disposition to return after several days to the same sleeping place, but this homing tendency was not observed in 1973. This discrepancy can perhaps be attributed to the fact that the two expeditions worked in different areas under different weather conditions. Observations on the plants eaten, on the association between tortoises and certain birds, and on some other aspects of tortoise behaviour such as walking speed and responses to sounds are also described.
Winter whitening of Scottish Mountain hares (Lepus timidus scoticus) in relation to daylength, temperature and snow‐lie
Authors: JACKES ANNE D. , WATSON ADAM
Published: August 2009

Changes in the coat colour of Scottish Mountain hares (Lepus timidus scoticus) were measured in the field. The rate of change varied between years, as did the extent to which the hares turned white. The data on these aspects were compared with changes in daylength and with variations in air temperature and the period of snow‐lie.
Population dynamics, distribution patterns and life cycles of Neobisium muscorum and Chthonius orthodactylus (Pseudoscorpiones: Arachnida)
Authors: Goddard Susan J.
Published: August 2009

The population dynamics, life cycles and distribution patterns of Neobisium muscorum (Leach) and Chthonius orthodactylus (Leach) were studied over a two year period in a Chiltern beechwood site. The data obtained for the two species are compared, and the importance of pseudoscorpions in the beechwood community is discussed.
Limb movements and locomotor function in the California sea lion (Zalophus californianus)
Authors: English Arthur Wm.
Published: August 2009

The peculiar amphibious mode of life of California sea lions suggests that their locomotor systems may contain adaptations both to life on land and in the water. Previous studies of their locomotor behaviour have been either superficial or based on inferences which were derived from limb structure. Limb movements associated with locomotor behaviour in California sea lions are described on the basis of frame‐by‐frame analysis of slow motion cinematography of typical aquatic and terrestrial locomotor sequences. Results are compared to reports of terrestrial and aquatic locomotor behaviour in fissiped carnivores, whose locomotor behaviour is presumed to reflect the framework from which the locomotor behaviour of sea lions was derived. The major distinction between sea lions and fissipeds in terms of aquatic locomotor behaviour involves the use of the forelimb in sea lions. Propulsive thrust is generated by medial rotation, adduction and retraction of the forelimbs in sea lions, in contrast to nearly pure limb retraction in fissipeds. The major features which distinguish terrestrial locomotor behaviour in sea lions from that of fissipeds are use of the manus as a transverse rather than sagittal propulsive lever and extensive use of posterior axial and head and neck movements rather than hindlimb movements. The biomechanical implications of these movements are used to elucidate their potentially adaptive features.
Locomotion, pedal retraction and extension, and the hydraulic systems of Bullia (Gastropoda: Nassaridae)
Authors: Trueman E. R. , Brown A. C.
Published: August 2009

Surface locomotion and burrowing by Bullia digitalis have been analysed by use of ciné film and electronic recording. Both movements are shown to be carried out by a series of steps in which the propodium is first extended whilst the snail is anchored by the posterior of the foot (penetration anchor) and, when buried, also by the shell; secondly the shell is drawn forwards and downwards towards the anchored propodium (terminal anchor). The extremely flattened foot of this snail contains a greatly enlarged pedal sinus containing blood and functions as a hydraulic organ. This contrasts with the foot of most gastropods, e.g. Patella, which crawl over hard surfaces and have no large fluid filled pedal cavity.

During each step, or digging cycle, there are two pressure pulses, one effecting propodial extension, the second occurring as the shell is drawn forwards. The pedal haemocoel is isolated from the remainder of the circulation for at least part of the locomotory cycle so enabling the foot to function as a fluid‐muscle system at constant volume. Bullia exhibits convergence with burrowing bivalve molluscs having a similar pattern of alternating anchorages in sand and in both water is ejected from the mantle cavity to liquefy the sand in front of the shell.

The energy cost of burrowing by B. digitalis is estimated to be 6.6 times 10‐6 J/mg dry tissue weight, a figure comparable to that of the clam Donax provided that burial occurs at a similar rate. By contrast the energy requirement for Bullia to move over the surface of sand is about one tenth of that for burial.

Pedal extension involves both blood flow, so that the foot may function as a hydraulic system, and direct muscular antagonism between the fibres of a three dimensional muscle network in the opercular muscle. When the snail is extended the shell contains some sea‐water which plays a dynamic role in pedal expansion and retraction independently of the pedal blood sinus. The possible role of this cavity in other prosobranchs is discussed.
Location before emergence of the female bee, Centris pallida, by its male (Hymenoptera: Anthophoridae)
Authors: Alcock John , Jones C. Eugene , Buchmann Stephen L.
Published: August 2009

Large numbers of males of the bee Centris pallida Fox have been observed patrolling areas in which females are emerging. Males locate specific sites at which a buried bee is about to emerge and dig down to meet the other individual, male or female. If it is a female, mating is initiated when she scrambles into the excavation pit created by the male. Males fight intensely with one another for possession of digging sites and for unburied virgin females. Experiments indicate that males locate conspecifics beneath the surface on the basis of extremely non‐specific olfactory cues; they are capable of locating buried honey bees and other insects. The evolution of digging behaviour is traced to selection favouring males that are first to reach a virgin female which will mate just once in her lifetime. A number of examples are given of other insects that have evolved similar abilities, apparently in response to similar selection pressures.
Body size and composition of Crabeater seals (Lobodon carcinophagus), with observations on tissue and organ size in Ross seals (Ommatophoca rossi)
Authors: Bryden M. M. , Erickson A. W.
Published: August 2009

Linear body measurements and body weights of 17 Crabeater seals and four Ross seals were recorded, and the relationships of weight to linear dimensions were calculated. There were no significant differences between sexes of these relationships in Crabeater seals. All Ross seals were males.

The major body components (blood, fat, skin, muscle, bone, connective tissue and viscera) of seven Crabeater seals were weighed after dissection.

Blood, fat and skin of two Ross seals were weighed. Weights of 22 visceral organs of the same animals, and linear bone dimensions of eight Crabeater seals and skull measurements of five Ross seals were recorded.

There was no significant difference between sexes or ages in body composition of Crabeater seals. Relatively, Crabeater and Ross seals had less blood (9–10% body weight) than Elephant seals, and less fat (21–22% body weight) than most other marine mammals. The low body fat content may have been attributable to season and physiological status of the animals when dissected. The percentages of body weight represented by the other major components of Crabeater seals were: skin 8%, muscle 44%, bone 10%, connective tissue 0.7% and total viscera 8%. These figures, and the relative sizes of individual organs, were discussed in relation to their possible function in Crabeater and Ross seals.
The breeding of the Sooty tern Sterna fuscata in the Seychelles and the effects of experimental removal of its eggs
Authors: Feare Christopher J.
Published: August 2009

In the Seychelles the eggs of the Sooty tern Sterna fuscata are collected for human consumption. A reduction in the number of Sooty terns breeding in exploited colonies has been attributed to over‐exploitation of the eggs. However, the population decline has been over‐estimated and factors other than exploitation have led to a reduction in the land area available to breeding colonies.

In the study colony, on Bird Island, egg laying was highly synchronous, and birds which laid at peak laying time had a higher reproductive success than those that laid early or late. The higher success of these birds was due to their being at the same stage of the reproductive cycle as their neighbours: this reduced losses of eggs to predators and losses of chicks due to pecking by adults and other chicks. Birds which laid late, which included young birds and birds which had lost their first egg and laid a replacement, were therefore penalized.

The ability to lay a replacement egg after loss of the first, was found experimentally to be much greater than previous estimates had suggested, and some individuals were induced to lay a third egg. Both the ability to relay and the success of replacement eggs declined seasonally. The laying of a replacement egg did not seem to place extra strain on the parents, and the lower weights of most replacements compared with first eggs was due to seasonal factors rather than to the inability of adults to produce a large second egg.

The food brought by the parents to the chicks consisted mainly of fish and squid, but frequent and abrupt changes in the species composition of the food suggested that food supplies were unpredictable. In 1973 chick growth was interrupted by two periods of food shortage, and although late hatched chicks experienced this food shortage early in their lives, starvation did not appear to be a major source of mortality.

The regulation currently in force in the Seychelles imposing a close season for egg collecting protects only late‐laid eggs, and since these have a very low success rate and can contribute little to future generations, there is no biological foundation for continuing this restriction. Adult mortality and age at first breeding are not known for Seychelles Sooty tern populations, and exploitation should be restricted to 10–20% of the birds that lay during the main laying period.
Observations on the peritrichous ciliate Scyphidia ubiquita from the west coast of Wales and a description of a new species
Authors: Fish J. D. , Goodwin B. J.
Published: August 2009

The peritrichous ciliate, Scyphidia ubiquita Hirshfield has been recorded on the west coast of Wales from the mantle cavity of snails belonging to the genus Littorina. The ultrastructure is similar to that described for specimens from the Pacific coast of the United States, but the scopula lacks a pellicular crest. Scyphidia acanthophorasp.n. from the mantle cavity of the top shells, Gibbula umbilicalis (da Costa) and Monodonta lineata (da Costa) is described on the basis of light, surface and transmission electron microscopy. It is distinguished from other scyphidians principally by the general body shape, form of the macronucleus and the ultrastructure of the scopula disc. Comparisons are made between this species and S. ubiquita particularly with respect to the ultrastructure of the scopula and the mode of attachment to the host.
The mechanism of burrowing of Sipunculus nudus
Authors: Trueman E. R. , Foster‐Smith R. L.
Published: August 2009

The method of burrowing of Sipunculus nudus L. and the movement beneath the sand is described. Pressures in the coelom have been measured and the forces exerted during burrowing are calculated.
Light intensity as a factor in the regulation of the density of symbiotic zooxanthellae in Aiptasia tagetes (Coelenterata, Anthozoa)
Authors: Steele R. Dunbar
Published: August 2009

Experiments designed to investigate the effect of different levels of illumination on the density of symbiotic zooxanthellae in the anemone Aiptasia tagetes (Duch. & Mich.) are described.

The anemones are found to regulate the densities of their zooxanthella populations to fixed levels which are dependent upon ambient light intensity.

Regulation is continuous and results from the interaction of increase in algal numbers, growth of host tissues, population of new host tissues by symbionts and extrusion of zooxanthellae by the host.

The nature of the process by which zooxanthellae are selected for extrusion is discussed and a scheme is outlined indicating the pathways through which the level of the algal population in Aiptasia, and other coelenterates, is believed to be controlled.
The genetics of bridling in guillemots from a study of hand‐reared birds
Authors: Jefferies D. J. , Parslow J. L. F.
Published: August 2009

The guillemot (Uria aalge) is a dimorphic species in the Atlantic part of its range with both a normal and a “bridled” form. The results of hand‐rearing guillemots of known parentage are compatible with bridling being a recessive variant from the normal, carried by a single gene on one of the autosomes. The first definite signs of bridling were seen as early as 54–66 days after hatching. There was no significant difference between the bridled and normal variants in the body weight and wing length of breeding adults and egg weight and hatching weight of the young. The likelihood of physiological differences between the two variants and also the factors determining morph‐ratio and its changes with time are discussed.
Growth, condition and reproduction in the Impala ram (Aepyceros melampus)
Authors: Hanks J. , Cumming D. H. M. , Orpen J. L. , Parry D. F. , Warren H. B.
Published: August 2009

The relationship between reproductive activity, body growth and condition in the male Impala is examined. Body growth is described by the use of the von Bertalanffy equation, and asymptotic values for each parameter are given together with the age at which these are attained. Seasonal changes in body condition are determined by the use of the kidney index and the fat content of the bone marrow, and this is related to body weight and the time of the rut. Growth and development of the reproductive organs with age and season are described in relation to reproductive activity.
The biology, ecology and functional aspects of the organs of feeding and digestion of the S.E. Asian mangrove bivalve, Enigmonia aenigmatica (Mollusca: Anomiacea)
Authors: Morton Brian
Published: August 2009

Enigmonia aenigmatica (Holten 1803) is an anomiid bivalved mollusc highly adapted for life attached to the trunks, projecting prop roots and leaves of mangrove trees. It is a characteristic member of the S.E. Asian mangrove community.

It exists in four growth forms, or morphs determined by the nature of the surface on which settlement takes place. It is also orientated and positioned on the tree trunks of Avicennia and the prop roots of Rhizophora, in relation to the long axis of the tree and the direction of the current. Further aspects of the biology and ecology of Enigmonia are discussed.

Enigmonia is monomyarian and lies on its right shell valve. This has resulted in an asymmetry which is of especial significance with regard to an understanding of the functional morphology of the organs of feeding and digestion in particular. The eccentricities seen in Enigmonia have been compared with the adaptations found in other anomiids in particular and other bivalves in general.

The feeding and digestive cycle of Enigmonia has been described and found to be correlated with the rhythm of the tide; it is essentially similar to that described for some other littoral bivalves.

The adaptations and specializations of Enigmonia are discussed in relation to its life in the mangal.
The adaptive and classificatory significance of certain quantitative features of the forelimb in primates
Authors: Ashton E. H. , Flinn R. M. , Oxnard C. E. , Spence T. F.
Published: August 2009

Quantitative osteological features of the primate brachium and antebrachium can be defined in relation to functionally significant contrasts in the principal muscle blocks. Such features, as shown by univariate and multivariate statistical study of a total of 525 sets of arm bones from 39 primate genera, demonstrate a broad correlation with the extent to which the forelimb is subject to tensile forces during locomotion. Man, in different features, resembles contrasting groups of non‐human Primates; in sum total of such characteristics, he is unique.

Other dimensional characters, defining more general features of the arm bones differentiate individually, but more especially in multivariate combination, between major taxonomic groups within both Prosimii and Anthropoidea.

In combination, the two groups of dimensions give a separation that is primarily taxonomic but which has a locomotor underlay.

When, in sum total, the dimensional characters of the arm are combined with those of the shoulder (where, as established in earlier work, the separation produced is almost exclusively locomotor), the initial division is in accordance with locomotor function of the forelimb—and especially the extent to which the limb is subjected to tensile forces. But there is a strong taxonomic underlay.

A method is thus provided for enquiry into both the taxonomic and functional significance of arm bones of fossil Primates.

The work, in addition to endorsing the classical concept of Man's retention of primitive mobility in the distal segments of his forelimb, also re‐emphasizes his uniqueness through arm mobility being associated with shoulder action principally caudal and ventral to the joint.