bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidermal structure and dynamics of the toad, Bufo bufo, deprived of the pars distalis of the pituitary gland
Authors: Budtz Povl E.
Published: August 2009

Structural changes and epidermal dynamics of the toad, Bufo bufo, were followed during 14 days after ablation of the pars distalis of the pituitary gland by taking skin biopsies 2, 17, 24, 40 and 65 hours, and 7 and 14 days after the operation.

The rate of differentiation of new cornified layers was moderately increased during the first week, and highly increased during the second week after removal of the pars distalis. The keratinization process became gradually abnormal with regard to initial keratinization (formation of a peripheral dense band) as well as to final keratinization (laydown of an interfibrillar dense matrix). The structural manifestations of the keratinization process after pars distalis ablation are discussed in relation to those of intact toads.

By counting the number of cells in the different “compartments” of the epidermis, it is shown that the total number of cells per length or square unit of stratum corneum remained constant in spite of at least five layers of stratum corneum being produced in a 14‐day period during which intact toads would have produced only one or two corneal layers. This shows that cell production can keep up with the increased rate of formation of corneal layers for at least 14 days after removal of the pars distalis, and consequently the rate of cell divisions must have increased.

It was further shown that the ratio between the number of cells in the stratum germinativum and in the stratum intermedium was decreased, which is discussed in relation to epidermal dynamics.

In Merkel cells, the number of granules increased, and eventually the granules became included within lysosome‐like bodies, indicating a secretory function of these cells. The findings are discussed in relation to the knowledge of mammalian Merkel cell structure and function.

No significant change was observed in the flask cells.

The control of amphibian epidermal proliferation, differentiation and moulting is discussed. It is concluded that these processes should be considered separately since they may not necessarily be coupled to one another and probably are differently controlled.
Modulatory multiplicity in the feeding mechanism in cichlid fishes, as exemplified by the invertebrate pickers of Lake Tanganyika
Authors: Liem Karel F.
Published: August 2009

Electromyography, motion analysis, osteology, myology and feeding behaviour of a morphologically specialized monophyletic lineage of cichlids in Lake Tanganyika have revealed that Eretmodus, Spathodus and Tanganicodus possess a feeding apparatus with a more extensive functional repertoire than that of any other teleost studied to date. When collecting a wide range of foods by inertial suction this trophic group can employ two strategies, a preprogrammed cyclical, energy saving pattern, or a modulated mode effected by extensive overlap of the firing patterns of multiple muscles resulting in a precise control of the magnitude and direction of suction. When dislodging sessile prey from the substrate the complexity of electromyographic and kinematic patterns increases. Because upper jaw protrusion can be effected and controlled independently from the complex couplings causing mouth opening and movements of the suspensory apparatus, a new decoupled model of upper jaw protrusion is proposed. The decoupled model predicts that upper jaw protrusion can be effected directly by contraction of epaxial muscles that raise the neurocranium, causing the premaxillae to slide anteroventrally. Upper jaw protrusion can be modulated continuously and directly by balanced cocontractions of antagonistic muscle sets giving the decoupled model an improved function over a very extensive range. The morphologically symmetrical muscular apparatus can function asymmetrically. Very pronounced asymmetrical firings of multiple muscles produce a continuously modulated jaw mechanism with an extensive repertoire.
Notochordal and elastic components of the axial skeleton of fishes and their functions in locomotion
Authors: Symmons Saida
Published: August 2009

Structural details of the notochord and elastic longitudinal ligaments (dorsal and ventral) of fish are presented with discussions on their possible contribution to the speed, power and modes of swimming by conferring an automatic spring‐like resilience to the vertebral axis as a whole. The notochord is also believed to function as a series of ring‐like hinges placed intervertebrally which dictates that the centra must be biconcave (amphicoelous) to support and house them. Examination of about 100 species shows that, whilst the dorsal ligament is always present, the ventral is found in primitive teleosts only. The phylogenetic significance of this in relation to the different efferent branchial systems will be submitted (with diagrammatic recording of dissections) for publication in the near future. The dorsal and ventral ligaments are suitably situated to assist the circulation of lymph and blood respectively in the small lateral vessels associated with the main longitudinal one of the appropriate system. Experimental work is required to test the hypotheses presented.
Allometry of the limb bones of mammals from shrews (Sorex) to elephant (Loxodonta)
Authors: Alexander R. McN. , Jayes A. S. , Maloiy G. M. O. , Wathuta E. M.
Published: August 2009

Measurements have been made of the principal leg bones of 37 species representing almost the full range of sizes of terrestrial mammals. The lengths of corresponding bones tend to be proportional to (body mass)0·35 and the diameters to (body mass)0·36, except in the family Bovidae in which the exponents for length are much nearer the value of 0·25 predicted by McMahon's (1973) theory of elastic similarity. Comparisons are made between mammals of similar size belonging to different orders.
Chromatophores and adaptation to coloured backgrounds in two colour types of the edible frog, Rana esculenta
Authors: Nielsen Hans Ingolf
Published: August 2009

The adaptation to coloured backgrounds of green and permanentiy brown specimens of Rana esculenta, and the anatomical and physical bases for their difference in colour were studied by means of reflectance microspectrophotometry and electron microscopy.

Adaptation to the lightness of the background took place in the green type, but not in the brown, whereas adaptation to hue and purity in both types seems negligible.

The iridophores of this species probably represent a λ/4‐system. The colour difference between the two types seems mainly to be caused by a difference in the selective reflectivity of the iridophores because of a difference in thickness of the platelets and the cytoplasmic interspaces. Furthermore there is a difference in the amount and, probably, composition of the xanthophore pigment.
The distribution of forest passerine birds and Quaternary climatic change in tropical Africa
Authors: Diamond A. W. , Hamilton A. C.
Published: August 2009

A cluster analysis of the distribution patterns of forest passerine birds in tropical Africa showed that they could be divided into three main distribution types: those of restricted distribution (144 species), those of disjunct distributions across West, Central and rarely to East Africa (65 species) and those of very wide distribution (81 species). Centres of species richness, endemism and disjunction coincide spatially, and are identified as forest refugia, where forest persisted throughout Quaternary climatic vicissitudes. These distribution patterns agree with modern interpretations of Quaternary palaeoclimatic changes, which show that glacial periods were arid and interglacials humid. Glacial periods were therefore too dry for montane forest to have spread into areas at present occupied by lowland forest, as advocated by Moreau and other supporters of ihe “pluvial” theory; montane forest is probably as extensive now as at any time during the Quaternary and there is no evidence of past connections between currently isolated montane forests. Bird distribution can be explained largely by slow dispersal outwards from refugia as climatic conditions allowed forest to spread, combined with a relaxing of the distinction between “montane” and “lowland” species under conditions of reduced interspecific competition.
Seasonal changes in the skin glands of Roe deer (Capreolus capreolus)
Authors: Adams M. G. , Johnson Elizabeth
Published: August 2009

Seasonal changes in the specialized skin glands of the forehead, metatarsal gland and interdigital regions of Roebucks are described and compared with glands of the general body surface. In both the forehead region and dorsal skin the sebaceous and apocrine glands enlarge as the testes enlarge and regress after the rut, but the glands of the forehead region are at least three times larger than those of the general body surface. The apocrine glands of the forehead region discharge by exocytosis except at the time of maximum secretion, which precedes total cell breakdown. In the metatarsal and interdigital regions the skin glands are enlarged throughout the year.
Vocalizations of nine species of rat (Rattus; Muridae)
Authors: Watts C. H. S.
Published: August 2009

The sounds produced by seven species of Rattus native to Australia and the Black rat (R. rattus) and the Brown rat (R. norvegicus), were investigated in the laboratory. Both audible and ultrasonic sounds were recorded and the ontogeny of the different vocalizations investigated. All nine species had the same basic repertoire of seven more or less discrete calls. Some calls varied more between the different species than did others. Similarly there were species' differences in the ease with which some calls could be elicited. Two major continua were identified, one audible and one ultrasonic. An attempt was made to put the vocalizations recorded into an evolutionary perspective.
The use of fish vertebrae in scats for estimating prey size of otters and mink
Authors: Wise M. H.
Published: August 2009

A method of using fish vertebrae in scats of otters and mink in order to estimate prey size is described. Significant positive correlations between fish fork length and length of abdominal and caudal vertebrae respectively were demonstrated and described for a series of reference fish of different species. Comparison of direct length measurements of fish fed to captive mink with length estimates obtained from vertebrae recovered in then scats and derived using the appropriate regression lines determined from the reference fish revealed a close measure of agreement and indicated that the method achieves a high level of accuracy. Use of vertebrae from scats for estimating fish length is considered to have several advantages over use of scales, and the method greatly extends the range, accuracy and value of the information that can be obtained from scat analysis.
Nocturnal loss of muscle protein from House sparrows (Passer domesticus)
Authors: Jones Marilyn M.
Published: August 2009

An overall loss of protein was considered to be the explanation for at least some of the observed loss of lean dry material from muscle of wild House sparrows overnight.
The structure of the glands in the angulus oris of the Bank vole Clethrionomys glareolus
Authors: Grifftths C. , Kendall Marion D.
Published: August 2009

The presence of glands opening to the angulus oris region of the bank vole Clethrionomys glareolus has been confirmed. The glands are similar in general to the apocrine sweat glands of man and other animals although histological differences were noted. Also there was a marked sex difference in the diameters of the lumens of the secretory tubules in this study (undertaken in the late autumn and early winter) The hairs into which the glands open are larger than other hairs in the region, and the surface pattern of the scales is inverted.
The influence of function on the development of bone curvature. An experimental study on the rat tibia
Authors: Lanyon L. E.
Published: August 2009

The effect of depriving the tibia of normal mechanical function during its growing period was investigated by performing a unilateral sciatic neurectomy in the gluteal region of young rats. The animals were kept for 16 months, after which their tibias were examined. On the neurectomized side there was a failure of this bone to attain its normal weight, thickness, cross sectional shape or longitudinal curvature. Attainment of the bone's overall length was uneffected.
The hydraulic system in a burrowing worm, Priapulus caudatus
Authors: Hammond R. A.
Published: August 2009

The function of the coelom as a locomotory hydraulic system in Priapulus caudatus has been examined and discussed. Pressure changes within the coelom during burrowing have been measured and used to monitor the activities of the muscular system.
The ecology, structure and functions of social play in Bighorn sheep (Ovis canadensis)
Authors: Berger Joel
Published: August 2009

Social play was studied in Bighorn sheep (Ovis canadensis) by examining its structure in two natural populations and by inferring functions through sexual differences in behaviour. Lambs discriminated the size of lambs with which they played. During contact play they responded most often to similarly sized individuals, whereas in locomotor play they chased and followed all sizes. Males engaged in more contact‐oriented play than females. This evidence supports the idea that contact‐oriented play developed in part to provide training for combatant skills in males and locomotor play as part of a general anitpredator strategy in both sexes. Social play was severely restricted in a desert environment due to risks and personal injury. The implications of lack of play in natural populations are discussed.
The hind limb step cycle of Iguana and primitive reptiles
Authors: Brinkman Donald
Published: August 2009

The hind limb step cycle of Iguana is described and compared with other lizards. In generalized lizards with well developed limbs, the femur retracts through a large arc and rotates as it retracts, flexion of the crus on the metatarsus occurs during the initial part of the propulsive phase and extension of the knee and ankle during the final part, the crus rotates to face laterally, the metatarsus is laterally directed at the time of pedal plantarflexion, and pedal plantarflexion involves an initial rotation of the metatarsus around its long axis followed by an extension of the ankle joint. The evolutionary significance of the differences in the hind limb step cycle of lizards and salamanders is considered and it is shown that in many, but not all, features, primitive reptiles would have been like salamanders. The primitive step cycle differs from the mammalian pattern in the large amount of rotation of the limb segments, the large amount of femoral retraction, and the reduced amount of lateral movement of the hip relative to the knee that occurs during femoral retraction.
Size, maturation and the social control of sex reversal in the coral reef fish Anthais squamipinnis
Authors: Shapiro Douglas Y.
Published: August 2009

A major hypothesis to explain the causal initiation of protogynous sex reversal is that females change sex upon reaching a critical size. A study of the coral reef fish Anthias squamipinnis shows that the size hypothesis does not hold. Females from two neighbouring, but spatially discrete and probably genetically homogeneous populations on Aldabra Island changed sex at distinctly different sizes. Previous laboratory and field studies in which sex reversal has followed the removal of a male from social groups have been uncontrolled and thus permit the interpretation that sex reversal is caused by non‐specific social disruption or by causes other than male removal. In this study, a male was removed from each of eleven single‐male and five multi‐male social groups in the laboratory (N= 8 male removals) and in the field (N= 19 male removals). In each group, the result was that one female changed sex. Laboratory controls made it unlikely that sex reversal was induced by non‐specific disruption and field observations showed that sex reversals resulted from male removals and were not coincidental, ongoing events. Previous statements that sex change is controlled by the presence or absence of a male, by inhibition of a female's tendency to change sex, or by aggression or dominance are shown, by an analysis of the complexity of issues, to be premature. Gonadal histology on 130 specimens confirmed that this species is a monandric, protogynous hermaphrodite and provided details of gonadal transformation.
The biology and functional morphology of Chlamydoconcha orcutti with a
Authors: Morton Brian
Published: August 2009

Two specimens of the exceptionally rare Chlamydoconcha orcutti Dall 1884 have been
Some properties of Red deer (Cervus elaphus) at exceptionally high population‐density in Scotland
Authors: Mitchell Brian , Crisp Janet M.
Published: August 2009

This paper records some features of Red deer (Cervus elaphus L.) at very high population density on a Scottish island. About half the total population was shot‐out in autumn 1974, and half the remainder in autumn 1975, with special searches for deer which had died of natural causes during the intervening year. In all, the animals examined amounted to 80% of the original population, and from the data gathered it was possible to (i) assess the structure and reproductive features of the original population; (ii) examine the level of animal performance at this exceptionally high population‐density; and (iii) check for any changes in performance arising from the initial reduction in density.

The sex‐ratio of adults in the original population showed a small excess of hinds, stags being apparently subject to a higher mortality rate than hinds after about six years of age. In performance, these deer were much the same as those living elsewhere on Scottish hill‐land at relatively high population‐density, i.e. with delayed puberty and poor breeding rates in hinds, and with much smaller adults than in woodland habitats. But, contrary to expectation, the general level of performance was not unusually low for Red deer on Scottish hill‐land, and there was no evidence of transmissible diseases or excessive parasitism. It was also surprising that the animals showed no improvements in performance following their first reduction; if anything, they were slightly poorer after one year at reduced density. This may have been a temporary consequence of the severe disruption of existing behaviour patterns brought about by the sudden loss of many groups of deer.
A new species of agamid lizard from Ghana
Authors: Macdonald M. A.
Published: August 2009

A new species of lizard of the genus Agama collected in the forest zone of Ghana is described. It occurs sympatrically with A. agama in S. W. Ghana and is related to that species and to A. paragama of Nigeria and Cameroun. The only known specimens form the type series. The known distribution based on sight records and specimens comprises the forest zone of Ghana west of 1d̀W and south of 7d̀N, but it is to be expected in Ivory Coast also. It appears to be rare or absent in the drier eastern Ghanaian forests. Although sympatric with A. agama, the two species occupy different habitats and rarely come in contact with each other, but in social behaviour they are similar. The new species may originally have been a rare animal of forest edge and natural breaks in primary forest. Recent disturbance of the forest may have allowed it to invade suitable artificial habitat within the secondary forest, arboreal plantations, and small clearings which are now the dominant habitats in the forest zone.
Factors affecting the reduction of the algal symbiont population in green hydra
Authors: Steele R. D. , Smith D. C.
Published: August 2009

For a given set of environmental conditions, the population of algal symbionts in green hydra remains at a constant level, indicating that the host animal exerts a regulatory influence on the size of its symbiont population. The experiments described here investigated those factors which can cause a reduction in the population size of symbionts: exposure to high light intensities, glycerol, darkness and the photosynthetic inhibitor DCMU. The purpose was to gain further insight into the mechanism of host regulation.

Treatment with high light intensity caused the most rapid reduction in algal numbers, and could result in complete “bleaching” in a few days. Glycerol caused a slower marked reduction, with partial “bleaching”. Darkness reduced algal numbers, but did not eliminate symbionts; the effect of DCMU in the light was similar. Glycerol and DCMU accelerated the effect of high light intensity. Electron microscopy of algal and animal tissues showed that high light intensity and glycerol treatment caused the algae to appear degenerate or even disintegrating, but darkness and DCMU only caused minor morphological changes. It is concluded that the mechanism for symbiont regulation is complex, and involves the following separate components: sloughing off host cells containing symbionts; variation in growth rate of host relative to symbiont; regulation of symbiont growth; ejection of symbionts; digestion of symbionts (rare); detection of photosynthetic incompetence; detection of dead cells.
The copepod Salmincola edwardsii as a parasite of Salvelinus alpinus in Britain, and a consideration of the so‐called relict fauna of Ennerdale Water
Authors: Fryer Geoffrey
Published: August 2009

The lernaeopodid copepod Salmincola edwardsii is recorded for the first time in the British Isles as a parasite of the salmonid fish Salvelinus alpinus. Material from Ennerdale Water in the English Lake District is described and illustrated and evidence of the occurrence of the same species in four Scottish lochs is presented. An interesting biological feature of the Ennerdale population is that egg size varies almost three‐fold in terms of volume in different individuals. Ennerdale's fauna is unique among those of British lakes in that it includes two crustaceans, Mysis relicta (known also from Ireland) and Limnocalanus macrurus (known nowhere else in the British Isles), both of which have been claimed as “ice‐age” or “marine‐glacial relicts”. No satisfactory explanation of how Ennerdale could have acquired these animals has hitherto been put forward. A hypothesis which attempts to do so and which also accounts for the presence of Salmincola on the char of Ennerdale and of certain Scottish lochs, but not on populations of this fish in other Lake District lakes, is put forward. This utilizes knowledge of the biology of the animals in question, such information as is available concerning the disposition of the ice in the area at the time of its retreat, and the record of the post‐glacial history of the Cumbrian lakes as preserved in their sediments.
Force, function and mechanical advantage in the chelae of the American lobster Homarus americanus (Decapoda: Crustacea)
Authors: Elner Robert W. , Campbell Alan
Published: August 2009

The dimorphic chelae from both sexes and a wide size range of American lobsters, Homarus americanus, were studied with respect to allometry, mechanical advantage, closer muscle apodeme area and occlusive surface morphology. The maximum forces produced by the crusher and cutter chelae were estimated by an in vitro and a static in vivo technique. Another in vivo technique, involving strain gauges, was used to measure the forces delivered by crusher chelae. The latter technique gave data on force pulse duration and frequency, and in combination with a video‐recording system could be useful for future studies of predation behaviour. The maximum forces generated increased with chela height for both crusher and cutter chelae. A maximum force of 256 Newtons (N) was recorded near the middle of the crusher dactyl from a 172‐mm carapace length lobster, by the strain gauge technique. Crusher chelae developed larger maximum forces than cutter chelae of the same height. This was attributable more to the crusher chela's higher mechanical advantage than to its developing higher input forces. The mean mechanical advantage for male crusher (0.33) was significantly higher than that for female crusher chelae (0.29). Male and female cutter chelae had the same mean mechanical advantage values (0.16). Values for maximum stress developed during contraction in both the crusher and cutter chela closer muscles decreased with chela size. The morphology of the chelae correlated to the forces produced and predation behaviour.
The occurrence of the Pigmy shrew Sorex minutus on moorland, and the implications for its presence in Ireland
Authors: Yalden D. W.
Published: August 2009

Throughout most of its range in western Europe, the Pigmy shrew Sorex minutus is sympatricwith the Common shrew Sorex araneus but greatly outnumbered by it. This makes it difficult to explain the presence of the Pigmy shrew, in the absence of its congener, in Ireland. A limited pitfall trapping exercise in England has shown that in moorland on deep peat, the Pigmy shrew may in fact outnumber the Common shrew. Reference to the literature on the ecology of the two shrews shows that this result is readily explained by existing knowledge of their diet; earthworms are a major prey for Common shrews and are absent from waterlogged, acidic, peats. Further, evidence on the nature of the possible land bridge from Scotland to Ireland suggests that it was at best low‐lying, and probably partly flooded. By analogy with moorland, such a land bridge might have been suitable for Pigmy shrews but not for Common shrews.
Demography of Gorilla gorilla
Authors: Harcourt A. H. , Fossey D. , Sabater‐Pi J.
Published: August 2009

Data on population size, density and composition, biomass, group size and composition and reproductive rates are compared between populations in the two regions of gorilla

distribution, equatorial west and east central Africa. The Virunga Volcano population of the latter region is shown to be a good model for all populations. Information on age at maturity, birth rates, mortality rates of adults and immatures and migration of individuals within the population is presented but data are available only for the Virunga population. The significance of a knowledge of the pattern of migration of individuals to the genetic consequences of large reduction in population size is stressed.
Seasonal changes in a population of the nectar‐feeding marsupial Tarsipes spencerae (Marsupialia: Tarsipedidae)
Authors: Wooller R. D. , Renfree M. B. , Russell E. M. , Dunning A. , Green S. W. , Duncan P.
Published: August 2009

During 1978 and 1979 over 900 individuals of the mouse‐sized marsupial nectarivore Tarsipes spencerae were pitfall trapped in Banksia thickets on the south coast of Western Australia. In both years numbers were highest in spring, when nectar was most abundant and lowest during summer months when it was scarce. The larger number of males caught probably reflects their greater activity rather than their greater abundance.
Evidence of denticles and attachment fibres in the superficial layer of scales in two fishes: Carassius auratus and Cyprinus carpio (Cyprinidae, Teleostei)
Authors: Zylberberg L. , Meunier F. J.
Published: August 2009

An attempt is made to clarify the mechanisms of the scale anchorage in two Cyprinidae, the goldfish and the carp. Scanning and transmission electron microscope investigations

revealed the presence of two different structures, denticles and collagen fibre bundles involved in the anchoring processes. These strucures are located on the upper part of the

scales. Denticles form minute processes on the circuli of the anterior areas of the scales. Collagen fibre bundles arise from the superficial layer connecting the scale to the overlying dermis. These fibre bundles show structural similarities with the Sharpey's fibres and are named Sharpey‐fibre‐like bundles. Such fibres of attachment, not previously reported, can be considered as usual anchoring structures in fish scales.
Ranging behaviour and its relation to diet selection in Tana River Red colobus (Colobus badius rufomitratus)
Authors: Marsh C. W.
Published: August 2009

Ranging behaviour of a group of Red colobus monkeys, Colobus badius rufomitratus, on the Tana River, Kenya, is described. The main study group had a mean day journey of 603 in and an annual range area of 9 ha (measured in 0.25 ha quadrats). Relationships between ranging patterns and diet selection are sought on both spatial and temporal dimensions. Differential use of the annual range is related to the distribution of major food species, while the diversity of monthly ranging patterns is inversely related to the availability of young growth in the canopy. These findings lead to a discussion of why range areas at the Tana are much smaller than those reported from rain‐forest sites.
The skull and the jaw adductor musculature in some burrowing scincomorph lizards of the genera Acontias, Typhlosaurus and Feylinia
Authors: Rieppel Olivier
Published: August 2009

The skull and the jaw adductor musculature are analysed in a number of representatives of the Ethiopian scincomorph lizard genera Acontias, Typhlosaurus and Feylinia. Acontias and Typhlosaurus are closely related and are to be included in a single taxon, the Acontinae, provisionally classified as a subfamily of the Scincidae. The family Feyliniidae (including the genera Feylinia and Chabanaudia) is revalidated and an amended diagnosis is given, The Feyliniidae are a scincomorph family, possibly with gekkotan affinities.
Byssus thread strength in the mussel, Mytilus edulis
Authors: Price Hilary Ann
Published: August 2009

Mytilus edulis attaches to the substratum by means of a proteinaceous byssus complex. This consists of three portions: a root, embedded in the pedal tissues, a stem, continuous with the root but external to the body and a number of byssus threads attached proximally to the stem and distally to the substratum via adhesive discs. Byssus strength varies seasonally on the shore, in response to changes in wave action (Price, in press). As a decline in byssal attachment strength implies a decline in strength of the constituent threads, a study was undertaken to establish the extent to which byssus thread strength is determined by age. The ultimate tensile stress, ultimate tensile strain and Young's Modulus were measured in threads of known age and length and a stepped regression performed on the results. It was found that age and length correlate significantly with tensile stress and Young's Modulus. Length is a less important influence than age on tensile stress but has a greater effect than age on Young's Modulus. Tensile strain is independent of both length and age.
Ecological observations on epomorphorine fruit‐bats (Megachiroptera) in West African savanna woodland
Authors: Marshall Adrian G. , William Andrew N. Mc
Published: August 2009

Three species of Megachiroptera were studied in Mole National Park, Ghana, by systematic netting in various habitats and by observations of bats in the field and in captivity. This study, undertaken in July‐August 1974 and 1975, is a preliminary attempt to elucidate how these species partition the resources available to them, with particular emphasis upon roosting habits, food resources, and temporal and spatial differences in foraging behaviour. All three species give birth towards the beginning of the wet season and are probably polyoestrus. The larger species, Epomophorus gambianus, does not appear to compete with the other two due to differences in roosting habits and the food resources available to it consequent upon its larger size. The two smaller species, Micropteropus pusillus and Nanonycteris veldkampi, are similar in size. N. veldkampi is presumed absent from Mole in the dry season when food is scarce; in the wet season it may minimise competition by being better adapted for nectarivory, foraging later, and foraging at a greater height than M. pusillus.
A physiologically discrete population of chromatophres in Octopus vulgaris (Mollusca)
Authors: Andrews P. L. R. , Packard A. , Tansey E. M.
Published: August 2009

Specimens of Octopus vulgaris (Cuvier) immersed in cold sea‐water (4°C) exhibit a flashing display of brown chromatophores that we call “brown spots”. The spots, which flashed approximately once every three seconds, are distributed over the dorsal skin of the head, mantle and arms and correspond mainly with the distribution of the white spots and white streaks previously described, and appear to act as a screen for the patches composing the white spots. Flashing brown spots could be evoked in animals with the supraoesophageal brain removed but not in animals with local denervation of the skin.

The precise site of action of the cold is unknown but it is proposed that the nerves supplying the brown spot units are normally tonically inhibited and that the cooling process removes this inhibition and allows the spots to flash. They are particularly useful for the in vivo study of the control of chromatophores because they can be reliably activated and isolated from responses of other chromatophores.
A light and electron microscope study of the gills of larval lampreys (Geotria australis) with particular reference to the water‐blood pathway.
Authors: Lewis S. V. , Potter I. C.
Published: August 2009

The gills of ammocoetes of the Southern Hemisphere lamprey Geotria australis have been studied using light and electron microscopy. Emphasis has been placed on describing the structures and vessels involved in gaseous exchange, and on providing quantitative data for the water‐blood barrier, including diffusion distance, diffusing capacity and the relative volumes of the component tissues. Although lamprey gills lie inside rather than outside the branchial skeleton as in gnathostomatous fishes. the morphology and ultrastructure of the gill filaments and secondary lamellae of G. australis larvae are very similar to those of teleost fishes. The extensive blood spaces within the secondary lamellae are enclosed by pillar cell bodies and pillar cell flanges which support two layers of epithelial cells. The outer surfaces of the epithelial cells are ridged and covered in a flocculent material which probably represents mucus. Differences were observed in the components of the water‐blood barrier at the distal edges and at the surface of the secondary lamellae. At the distal edge, the lining of the marginal channel consisted of an endothelial cell rather than the pillar cell flanges which line the blood spaces of other regions. Based on light micrograph measurements, these differences result in a reduction in the arithmetic mean thickness of the water‐blood barrier from 3.62 μm over the pillar cells to 2.22 μm over the marginal channel. Using values for the water‐blood barrier obtained from light micrographs, the arithmetic and harmonic mean diffusing capacities were calculated as 1.1046 and 1.7589 ml O2min/mm Hg/Kg.
Breedng season, larval development and diseprsal of Lingula anatina (Brachiopoda, Inarticulata) from Townsville, Australia
Authors: Hammond L. S.
Published: August 2009

A discrete but protracted breeding season, extending from October to April, was defined for Lingula anatina from Townsville, Australia, using gonad indices, sizes of developing ova, occurrence of planktonic larvae and analysis of size frequency distribution of an adult population. Comparison of temperate and tropical records suggests that the duration of the breeding season is regulated by temperature. The minimum age at which larvae achieve competence to settle is approximately the same in temperate and tropical waters, but in both regions development and growth occur at a very variable rate. A number of morphological features which can be considered precursors to settlement are closely associated in their development, which may proceed in response to settlement cues provided by proximity to the substratum. The varying intensity of such cues in different environments may be responsible for delays before some larvae realize competence to settle, accounting for much of the variability in the development process. Accordingly, differences between collections of Indo‐West Pacific Lingula larvae can be rationalized; all records are now referred to L. anatina. Extension of pelagic larval life in lingulid larvae appears to involve a strategy different from that of most other marine invertebrates.
The pace of growth: An allometric approach to comparative embryonic and post embryonic growth
Authors: Calder William A.
Published: August 2009

Embryonic and post‐embryonic growth times are scaled to body size in a fashion quantitatively similar to physiological time scales. Previous studies have either perceived the allometry of physiological time only as a crude approximation or overlooked it entirely. Allometric analysis offers considerable promise for understanding comparative growth dynamics.
The underground passages and storage pits used in foraging by a nest of the termite Macrotermes michaelseni in Kajiado, Kenya
Authors: Darlington Johanna P. E. C.
Published: August 2009

Part of the system of underground passages and storage pits used in foraging by a nest of Mucrofermes michaelseni was excavated and is described in detail, and an attempt is made to quantify it. Densities as high as 1.9 m of passage and 21.4 storage pits per m2 were recorded in the main foraging zone, which is 10–35 m from the nest. The estimated total for the whole nest was just under 6 km of passage and 72,000 storage pits, in an area of about 8000m2
Estimates of mechanical stresses in leg muscles of galloping Greyhounds (Canis familiaris
Authors: Jayes A. S. , Alexander R. McN.
Published: August 2009

Films of Greyhounds galloping at maximum speed have been analysed, to determine the linear and angular accelerations of their legs. The masses and moments of inertia of the legs of dead Greyhounds, and the dimensions of individual leg muscles, have been measured. Hence the maximum stresses exerted during galloping, by various leg muscles, have been calculated.
Sexual reproduction in Epistomia bursaria (Bryozoa: Cheilostomata), an endozooidal brooder without polypide recycling
Authors: Dyrynda P. E. J. , King P. E.
Published: August 2009

Epistomia bursaria L. is unusual amongst cheilostomes in that there is only one polypide generation per autozooid, together with endocoelomic embryonic brooding and larval viviparity. This combination, which gives the minimum possible fecundity of one larva per gynozooid is only known for one other cheilostome species, the majority of the rest being extracoelomic ovicellate brooders with polypide recycling. The greater fecundities exhibited by ovicellate and non‐brooding recyclers may offset the smaller degree of protection afforded by these reproductive strategies.

Spermatogenesis and oogenesis are examined ultrastructurally. Whereas spermatogenesis is similar to that of other cheilostomes studied previously, oogenesis is very different. The egg at maturity is small and alecithal. Evidence suggests that endozooidal self‐fertilization occurs. Whereas nutrient for spermatogenesis and oogenesis is probably intrazooidal in origin, that for embryogenesis is derived inter‐zooidally.

It is suggested that the combination of endocoelomic brooding, larval viviparity and one polypide generation may be a primitive feature from which recycling and extracoelomic brooding may have evolved.
Social differences in the subcaudal scent gland secretion of Apodemus sylvaticus (Rodentia: Muridae)
Authors: Gorman Martyn L.
Published: August 2009

This paper presents a preliminary chemical analysis of the secretion of the subcaudal scent gland of the Woodmouse Apodemus sylvaticus. A statistical analysis of samples from various sites in the United Kingdom and Eire shows that there are individual differences in the secretion, differences between the sexes, differences between juveniles and adults and differences between populations.
Oxygen uptake and heart rate in young Green turtles (Chelonia mydas)
Authors: Davenport J. , Inagle G. , Hughes A. K.
Published: August 2009

Oxygen uptake. heart rate and breathing frequencies were monitored in yearling Green turtles. Routine fed animals used about 100μ O2 g live turtle‐1 h‐1 at 25d̀C; this value was not significantly affected by size or short term food deprivation. Starved turtle showed a doubling of oxygen uptake after a satiation meal and heightened uptake persisted for five days. Between 15d̀ and 30d̀C oxygen consumption increased with rising temperature; below 15d̀C there was falling temperature. Vigorous activity increased oxygen uptake to two or three times thr routine fed levels.

Turtles swimming gently at 25d̀C exhibited a heart rate of around 46–48 beats min‐1; this rose to 64–68 beats min‐1 during vigorous and continuous activity. Contrary to expectations profound bradycardia was not seen during diving; even during 10 min dives a rate of 25–28 beats min‐1 was sustained. Significantly lower heart rates were only seen in turtles which were apparently asleep.
Factors affecting population density, group size and territory size of the European badger, Meles meles
Authors: Kruuk Hans , Parish Tim
Published: August 2009

This paper discusses the relationship between the distribution and biomass of the main prey of European badgers, Meles meles and the badgers group size, territory size and population density. The distribution of areas rich in earthworms, Lumbricus spp., is correlated with badger range size, whilst badger group size increases with the biomass of worms per badger territory and badger density increases with overall worm biomass. Regulation of badger density in an area is likely to take place through regulation of group size, in the absence of other factors such as persecution and lack of suitable sett‐sites.
An ultrastructural study of spermiatogenesis and spermatozoal morphology in Sparganophilus tamesis (Sparganophilidae, Oligochaeta, Annelida)
Authors: Jamieson* B. G. M. , Fleming** T. P. , Richards** K. Sylvia
Published: August 2009

Spermatogenesis in Sparganophilus tamesis results in a filiform spermatozoon of the advanced type. Structures in proximal‐distal sequence are the slender acrosome, the extremely elongate nucleus, the short cylindrical midpiece and the long flagellum. The acrosome is unique in those Lumbricina so far studied in persistence of the subvesicular space in the anterior (proximal) bulb formed by the primary acrosome vesicle, external to the acrosome tube and in extension of the acrosome rod into this proximal subvesicular space. A further unusual feature is the very long basal chamber in the acrosome tube, distal to the rod, as in the Phreodrilidae. The acrosome tube has a distal limen and its junction with the nucleus is domed. There is little similarity with the acrosome of the Lumbricidae, a family with which the Sparganophilidae have recently been grouped. The midpiece has the highest number of mitochondria yet recorded for oligochaetes. The number is deduced to be eight, of which seven are normally visible in cross section because one of the mitochondrial loci consists, uniquely for the Oligochaeta, of two mitochondria aligned longitudinally in tandem. The structure of the flagellum, including the arrangement of its peripheral glycogen granules, is typical for oligochaetes. The spermatozoon is straight, lacking a spiral coil or keel. These results are discussed in relation to oligochaete phylogeny.
The comparative morphology of the photophores of the squid Pyroteuthis margaritifera (Cephalopoda: Enoploteuthidae)
Authors: Butcher* S. , Dilly* P. N. , Herring** P. J.
Published: August 2009

Pyroteuthis margaritifera has morphologically distinctive photophores on the tentacles, eyeball and in the mantle cavity. The photogenic tissue in each photophore is identical, has a blue‐green fluorescence and luminesces on treatment with dilute hydrogen peroxide. The photocytes frequently contain organized fibrillar material akin to that in the photocytes of certain other cephalopods. Several different types of blood vessel are present among the photocytes, including some, apparently restricted to the photophores, with a microvillous endothelium. Haemocyanin is present not only within identifiable blood vessels but also in some intercellular spaces.

On the basis of their characteristic optical systems the photophores can be separated into three types: (1) tentacular; (2) ocular and anal; (3) branchial and median abdominal. The tentacular photophores have collagenous reflector and light guide systems and the median ones are double organs. The ocular and anal organs do not have collagenous optical structures but an elaborate variety of reflective iridosomes. Those in the aperture of the photophores appear to act as interference filters. The branchial and abdominal organs have iridosomes as the major reflective tissue but collagenous fibrils function as light guides in the aperture of these organs and their emission is diffuse rather than collimated.
Phylogenetic relationships of the tilefish family Branchiostegidae (Pereiformes) based on comparative myology
Authors: Marino Robert P. , Dooley James K.
Published: August 2009

The adductor mandibulae complex of the tilefish family Branchiostegidae contains five major subdivisions (A1α, A1β, A2, A3α and A3β). No other group of fishes among those examined exhibited the degree of complexity found among the branchiostegids. The closely related sand tilefishes (Malacanthidae) have a less complex adductor mandibulae musculature, lacking an A3β muscle. The proposed phylogeny of the branchiostegids is based upon: (1) the A3β′, A3β″ and A1β subdivisions, (2) overall degree of development of the adductor mandibulae (distinctness, origins, insertions, and degree of aponeurotic development). The phylogenetic implications of the adductor mandibulae complex are discussed.
Seasonal changes in African ungulate groups
Authors: Underwood R.
Published: August 2009

Size and age/sex composition were recorded for social groups of seven ungulate species over two years. Most species showed seasonal changes which were correlated with rainfall or with their breeding cycle. Group sizes tended to increase during the rainy seasons, although some species, particularly wildebeeste, also aggregated strongly on fresh burns. For all seasonally breeding species, the average male had little contact with females during the conception peak, although female herds almost invariably had about one attendant male.
Feeding behaviour and feeding ecology of the Octocorallia (Coelenterata: Anthozoa)
Authors: Lewis John B.
Published: August 2009

The feeding behaviour of some 30 species of Octocorallia was examined in the laboratory and in the field. All of the species from the Orders–Alcyonacea, Gorgonacea, Stolonifera and Telestacea, appear to have a common, basic feeding strategy. Fine particulate matter and zooplankton were captured in a raptorial manner by the tentacles and pinnules. Upon capture of food particles, the tentacles were flexed rapidly inwards and closed or wiped across the mouth. At the same time the mouth opened and ingestion was accomplished by directional ciliary currents in the mouth and the pharynx. Food capture by means of mesenterial filaments, mucus strands or ciliary currents was not observed. The examination of gut contents of Alcyonacea showed that they feed upon zooplankton. Epibenthic copepods from the demersal coral reef zooplankton were an important element of the diet of alcyonaceans.