bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological changes to the heart and associated blood vessels during lamprey metamorphosis
Authors: Percy Lord Richard , Potter I. C.
Published: March 2009

Representatives of all seven stages in the metamorphosis of the parasitic lamprey Geotria australis and the nonparasitic lamprey Lampetra planeri have been used to describe the way in which the heart and associated blood vessels are modified or lost during metamorphosis from the larval (ammocoete) to adult condition. Attention is focused on discussing the possible functional significance of these alterations and on resolving major anomalies in the literature regarding the adult circulation. The metamorphic changes to the heart and associated blood vessels do not commence until external signs of transformation are apparent and, despite the different modes of adult life of the two species, they subsequently undergo a similar pattern of modification and loss. While the left duct of Cuvier has disappeared by the end of Stage 5, the right duct remains and its walls increase in thickness throughout metamorphosis. The small left dorsal hepatic vein, and also often the right dorsal hepatic vein which in ammocoetes enter the left and right ducts of Cuvier, respectively, are lost during metamorphosis. The median ventral hepatic and prominent inferior jugular veins, which both pass into the ventral region of the sinus venosus at the same level, remain in the same position as in the ammocoete. By Stage 4, the larval hepatic portal vein, which in the ammocoete entered the posterior dorsal tip of the liver, has undergone extensive degeneration and the new adult hepatic portal vein passes into the mid‐dorsal region of the liver. The pericardium develops during metamorphosis through a forward and upward growth of connective tissue on the anterior face of the liver and from connective tissue on the ventrolateral, dorsolateral and dorsal inner surfaces of the body wall. The development of cartilage can be detected in parts of this structure as early as Stage 3. The loss of certain blood vessels, the development of a pericardium and the alterations in the position and structure of the chambers of the heart and associated blood vessels which occur during metamorphosis, are all interpreted as adaptations for accelerating blood flow and increasing the pumping efficiency of the heart. These features would be of advantage to adult lampreys, which are more active than ammocoetes.
The major intrinsic pancreatic ducts of the rhinoceros
Authors: Cave A. J. E.
Published: March 2009

A first‐time account is given of the parenchymal subdivisions and related duct system of the pancreas in Didermocerus, Diceros and Ceratotherium. In each of these rhinoceros forms a small, superficial portion only of the caput pancreatis is drained by a Santorini duct opening directly into the duodenum. The remainder of the pancreatic parenchyma is drained principally by a transverse and an ascending duct, from whose union arises a short Wirsung duct which enters the duodenum through an intermediary Vaterian ampulla situated within a prominent papilla duodeni.
Characterization of boreholes by Octopus dofleini in the bivalve Saxidomus giganteus
Authors: Ambrose R. F. , Leighton B. J. , Hartwick E. B.
Published: March 2009

Octopus dofleini (Wulker) drills holes in mollusc shells, enabling it to introduce venom. Boreholes in the bivalve Saxidomus giganteus (Deshayes) were generally irregular. Thick shells were more likely to have incomplete boreholes, and the diameter of completed boreholes was larger than in thin shells. A comparison of boreholes to fractured and artificially drilled surfaces suggests that O. dofleini employs chemical dissolution of the shell during drilling.
Taxonomic value of pore pattern in the integument of calanoid copepods (Crustacea)
Authors: Mauchline J.
Published: March 2009

Integumental sensilla and gland openings occur in the integuments of calanoid copepods in what are, essentially, bilaterally symmetrical patterns. Their presence is most easily determined by digestion of the integument in hot alkali to destroy the soft tissues. The sites of the sensilla and gland openings are then seen in the integument, stained with chlorazol black, as spots of light under the light microscope. These pores, or holes, in the integument result from the digestion of the neural innervation of the sensilla or from the digestion of the ducts of the glands which traverse the integument from the epidermis to the outside. The patterns of distribution of these pores are examined in 249 species representing 89 genera ascribed to 28 families of the calanoid copepods. The investigation is confined to the patterns in the five metasomal segments of the species. The metasomal pattern is peculiar to most species and represents a species signature. The pore signature of an individual species consists of several constituent elements. The pores group into several complexes within which individual pores may or may not be developed in that species. The primary elements of these complexes are subscribed to by the signature of the superfamily to which the species belongs. The superfamilial signature with the addition of secondary elements forms the familial signature which is further diversified to form the generic signature. The generic signature is usually further complicated to produce the species signature. In some genera, however, the generic metasomal signature is not complicated to any degree in the constituent species and the distinctive elements of the species pore signature are found more or less restricted to the urosomal segments.

These patterns of pores that can be traced from the species and genus through to the corresponding superfamily form one suite of pores. A second suite of pores is developed within some genera and families that probably represents specialization within these taxa. There is a gradual modification of the pore signatures that corresponds with current concepts of the phylogeny of the Copepoda.
Initial stages of food ingestion by Sepia officinalis (Mollusca: Cephalopoda)
Authors: Guerra A. , Nixon M. , Castro B. G.
Published: March 2009

The cuttlefish ingests much skeleton from the crustaceans and fish it preys upon. The skeletal pieces are relatively large and their dimensions bear a close relationship to the length of the buccal mass and diameter of the oesophagus. The structures of the buccal mass are instrumental in the breakdown of prey and orientation of long pieces of skeleton to ensure their entry into the oesophagus. Many pieces of skeletal material present in the stomach contents still have attached muscles, showing that there is little, or no, external digestion. Skeletal material may be important for long‐term maintenance of young Sepia in captivity.
Studies on Priotrochus obscurus and the systematic position of Priotrochus (Mollusca: Gastropoda: Trochidae)
Authors: Herbert D. G.
Published: March 2009

The systematic status of Priotrochus Fischer, 1879 and the taxonomy of its type species, Trochus obscurus Wood, 1828, are discussed. Although previously regarded as a subgenus of Monilea, observations on the radula and external anatomy reveal little similarity with Monilea and the Umboniinae as a whole. Greater similarity exists with members of the Monodontinae and a position, at generic level, in that subfamily is suggested. The extinct Trochus ponsonbyi Sowerby, 1888, is maintained as a subspecies of Priotrochus obscurus.
Egg‐shells in mites. Vitelline envelope and chorion in a water mite, Limnochares aquatica L. (Acari, Limnocharidae)
Authors: Witaliński Wojciech
Published: March 2009

Results of ultrastructural investigations (SEM and TEM) of the formation and structure of eggshells in the water mite, Limnochares aquatica, are presented. The material of the vitelline envelope is secreted in two stages by the oocyte commencing vitellogenesis. The vitelline envelope is later transformed into endochorion and during the passage through the reproductive tract it becomes covered with exochorion, produced by the female reproductive accessory gland. The exochorion swells in water to acquire a foamy structure.
The maximum average bite force for a given jaw length
Authors: Greaves W. S.
Published: March 2009

Major osteological landmarks were used to prepare idealized drawings of mammalian and reptilian lower jaws. Measurements from these drawings allowed the average output or bite force, along the entire jaw, to be calculated for many different anteroposterior positions of the input or muscle force. In the mammalian drawing, the maximum average bite force is exerted when the resultant force is located at about 30% of the way along the jaw from the joints. Because of geometric differences in the reptilian drawing, a resultant positioned at 20% of the way along the jaw exerts the maximum average bite force; a maximum force that is smaller than that in the mammalian case. The estimated location of the muscle resultant in actual cases corresponds to these calculated positions. Therefore, in real animals, the muscles are located in the position that produces the largest average force for any jaw length. The geometric changes necessary to transform the idealized reptilian drawing, with a smaller maximum average bite force, into that of the mammalian drawing, with a larger maximum force, are the same as those changes seen in the fossil record of the reptile/mammal transition. This finding suggests that the morphological changes that occurred in the jaws increased the average bite force in the primitive mammals.
Factors influencing the fecundity of Moniliformis moniliformis (Acanthocephala): constant diet and varied dose
Authors: Crompton D. W. T. , Arnold S. E. , Walters D. E. , Keymer A. E. , Marrs R. W.
Published: March 2009

Aspects of the reproductive performance of Moniliformis moniliformis were investigated in rats allowed to feed ad libitum on a purified diet containing 1% (w/w) fructose as an energy source for the worms. The rats were infected with either 10, 20, 40 or 80 cystacanths each with the intention of investigating density‐dependent effects on worm fecundity. The establishment of the worms in the gut was independent of dose, but survival, growth and reproductive performance generally were shown to be related to the infective dose given to the rats. The effects could not be related to the absolute numbers of worms present in the small intestine at post‐mortem examination. In general, some unidentified regulatory process appeared to operate to create severe density‐dependence in survival so that surviving parasites were not present in numbers expected to generate competition. Attainment of sexual maturity, growth and the production of mature eggs by worms from rats given doses of 80 cystacanths each were delayed compared with worms from rats given the other doses, but eventually the performance of the high‐dose worms caught up. Worms attached more anteriorly in the small intestine grew bigger and produced more mature eggs. Possible mechanisms responsible for the observed effects are discussed.
Tensile properties of calcified and uncalcified avian tendons
Authors: Bennett M. B. , Stafford Judith A.
Published: March 2009

The mechanical properties of turkey and heron leg tendons have been investigated in dynamic tensile tests. Heron tendons have properties similar to those found for various mammalian tendons. The Young's modulus and the density of turkey tendons increase with increasing calcification. Ultimate tensile stresses are similar to those found for uncalcified tendon, but Young's modulus may reach about 16 GPa, a value normally associated with bone. Calcification lowers the amount of strain energy that can be stored temporarily in the tendons of the legs. The contribution made by elastic strain energy storage to lowering the cost of running is reduced.
Melanophore comparisons in different forms of ambicoloration in the flatfish Pseudopleuronectes americanus and Reinhardtius hippoglossoides
Authors: Burton D.
Published: March 2009

The melanophores associated with contrasting manifestations of ambicoloration in two species, winter flounder (Pseudopleuronectes americanus) and Greenland halibut (Reinhardtius hippoglossoides), from the Pleuronectidae are compared microscopically. Winter flounder is a benthic inshore species, whilst Greenland halibut is a deep water species considered to spend the greater part of its life away from the sea floor, although the relatively thick blind‐side epidermis associated with a benthic life occurs in both species. Various forms of abnormal ambicoloration occur in some specimens of winter flounder. Melanophores from the flounder blind side are morphologically similar to those from the ocular side in the different forms of ambicoloration, although there are differences in melanophore densities. In Greenland halibut, ambicoloration is a normal characteristic which is considered to be secondarily acquired. The melanophores of the ocular side of Greenland halibut are similar to the melanophores of other Pleuronectidae, whereas those of the blind side are very different in morphology and size.
Host‐parasite relationships between two seal populations and two species of Corynosoma (Acanthocephala) in Finland
Authors: Valtonen E. Tellervo , Helle E.
Published: March 2009

Ringed seals (Phoca hispida botnica), from the Bothnian Bay, north‐eastern Baltic Sea were examined for acanthocephalan parasites in 1977–1982, and specimens from Lake Saimaa in south‐eastern Finland (P. h. saimensis) were examined in 1980–1981. The two seal stocks have been isolated from Arctic stock for 11,000 years and from each other for 8,000 years. Corynosoma strumosum and C. semerme were found in the Baltic seals, but only C. strumosum in those from the lake.

Eighty two of the ringed seals caught in the Bothnian Bay were infected with both Corynosoma species, one with a single infection of C. strumosum and one with C. semerme in autumn. The total number of C. semerme increased in relation to the number of C. strumosum in each set of seals both in autumn and spring. Corynosoma semerme was dominant in most seals in spring, but in only an average of 60% in autumn. The predominance of C. strumosum in 40% of the autumn material (range 33–80%) is of interest because species ratio favouring C. strumosum is not found in any more heavily infected paratenic fish host of Corynosoma in the Bothnian Bay. The change in the Corynosoma species ratio of seals in autumn may be explained by their exceptional feeding behaviour at this time of the year (total or partial fasting) and the suggested longevity of C. strumosum as compared with C. semerme. The stability of the acanthocephalan populations in ringed seals is documented.
The fin musculature of cuttlefish and squid (Mollusca, Cephalopoda): morphology and mechanics
Authors: KIER WILLIAM M.
Published: March 2009

The lateral fins of cuttlefish and squid consist of a tightly packed three‐dimensional array of musculature that lacks bony skeletal support or fluid‐filled cavities for hydrostatic skeletal support. During swimming and manoeuvring, the fins are bent upward and downward in undulatory waves. The fin musculature is arranged in three mutually perpendicular planes. Transverse muscle bundles extend parallel to the fin surface from the base of the fin to the fin margin. Dorso‐ventral muscle bundles extend from dorsal and ventral connective tissue fasciae to a median connective tissue fascia. A layer of longitudinal muscle bundles is situated adjacent to both the dorsal and ventral surface of the median fascia. The muscle fibres are obliquely striated and include a core of mitochondria. A zone of muscle fibres with a more extensive core of mitochondria is present in both the dorsal and the ventral transverse muscle bundles. It is hypothesized that these muscle masses include two fibre types with different aerobic capacity. A network of connective tissue fibres is present in the transverse and dorso‐ventral muscle masses. These fibres, probably collagen, are oriented at 45 to the long axes of the transverse and dorsoventral muscle fibres in transverse planes.

A biomechanicayl analysis of the morphology suggests that support for fin movements is provided by simultaneous contractile activity of muscles of specific orientations in a manner similar to that proposed for other ‘muscular‐hydrostats’. The musculature therefore provides both the force and support for movement. Connective tissue fibres may aid in providing support and may also serve for elastic energy storage.
Burrow patterns of the mole rat Spalax ehrenbergi in two soil types (terra‐rossa and rendzina) in Mount Carmel, Israel
Authors: HETH GIORA
Published: March 2009

Complete burrow systems of the mole rat Spalax ehrenbergi (Rodentia; Spalacidae), from two sites on Mount Carmel in Israel, with different soil types (terra‐rossa and rendzina), were excavated and described here for the first time.

A comparison was made of burrow structure patterns in the two soils and of the sexes, with special attention to the features of the feeding tunnels.

The pattern in the rendzina revealed longer burrows with a longer main tunnel and fewer branches per metre of the main tunnel, while the pattern in the terra‐rossa revealed shorter burrows with a shorter main tunnel and a relatively higher number of branches. These differences can primarily be related to the different levels of food availability, which is higher in the terra‐rossa. It is suggested that each of the patterns reflects the mole rat's ability to optimize foraging efficiency in accordance with its given food availability.

The average total length of the males' burrows was much greater than those of the females' burrows in the rendzina soil. It appears that food requirements determine different burrow features of the sexes rather than reproduction requirements.

Other tunnel features (e.g. structural complexity, depth and width, segment length and spatial arrangement) and the factors which may affect them, as well as burrow structure of young mole rats and evidence of the underground dispersion of young mole rats, were presented and discussed.

Many similarities were found in a comparison of S. ehrenbergi burrow features with those of other solitary subterranean rodents.
The use of faecal counts for estimating populations of wall lizards (Podarcis muralis)
Authors: AVERY R. A. , PERKINS C. M.
Published: March 2009

Measurements of the rates at which droppings of wall lizards (Podarcis muralis) on Jersey appeared in, and disappeared from, the environment made it possible to formulate a simple mathematical model for the dynamics of faecal pellet populations. The model shows how, for a given lizard population, the number of droppings changes with time according to weather conditions. It was used to estimate lizard densities at a number of sites from daily pellet counts. There were significant differences in the densities of lizards between sites; possible reasons for these are discussed.
The family of huntsman spiders in Israel with annotations on species of the Middle East (Araneae: Sparassidae)
Authors: LEVY G.
Published: March 2009

The spiders of the family Sparassidae in Israel have been described and species of the Middle East and from adjacent faunae have been revised. They are amongst the main predatory spiders of the Old World deserts although some also occur in less arid environments. Systematic and ecological information is presented and patterns of their zoogeographic distribution are discussed. Type and non‐type material pertinent to the faunae investigated, deposited in a great number of European collections, has been re‐examined. Nearly all species have never been adequately described or illustrated. The genus Cerbalus, species of which have never before been recorded in Asia, is revised. Nonianus is likewise a new Asiatic record while Olios and Heteropoda are reported for the first time from Israel. The African Micrommata longipes Bösenberg & Lenz, 1895 is transferred to Pseudomicrommata, Cerbalus concolor Denis,1947 is newly placed in Cerbalopsis, and a new synonymy of the genus Marmarica Caporiacco,1928 with Cerbalus Simon, 1897 has been proved. The following new synonyms are defined: Heteropoda civilis (Reuss, 1834) together with Sparassus tersus (C. L. Koch, 1838), S. validus Thorell, 1875, S. cognatus O.P.‐Cambridge, 1876, 5. fontanieri Simon, 1880, and Eusparassus kronebergi Denis,1958 =Sparassus walckenaeri (Audouin, 1827); Cerbalus angustifrons Denis,1960, and C. sahariensis Jézéquel & Junqua,1966 =Cerbalus pulcherrimus (Simon, 1880); Olios impediens Denis,1947 = Olios suavis (O.P.Cambridge, 1876), new combination; Cebrennus sparassoides Caporiacco, 1921 = Cebrennus castaneitarsis Simon, 1880. Two new species are described: Cerbalus psammodes and C. negebensis. Key to the genera and detailed illustrations of diagnostic characters are provided for each species, and are readily applicable to species of adjacent countries.
The biology of Schizomus vinei (Chelicerata: Schizomida) in the caves of Cape Range, Western Australia
Authors: HUMPHREYS W. F. , ADAMS M. , VINE B.
Published: March 2009

The chelicerate order Schizomida is represented in Western Australia by a single species, Schizomus vinei Harvey, from caves in the semi–arid Cape Range on the North West Cape peninsula. Schizomus vinei occurs in eight of 170 caves known from the range but is found only in areas where the relative humidity exceeds 92%. The schizomids are associated with a rich fauna (at least 11 species) mostly of detritivores, some of which show troglobitic adaptations. They prey on the cave animals that feed on detritus and are known to eat oniscoid isopods, millipedes, cockroaches, worms and S. vinei.

The size class structure of the population in cave C 118 was strongly skewed negatively suggesting that the smaller size classes occupy interstices of the infill of sumps. Schizomids in this cave were found to be distributed at random up to the third nearest neighbour. The minimum population size, with 95% confidence, was estimated to be 1323 individuals. Schizomus vinei grew very slowly in vivaria. One female produced nine eggs which did not survive.

Schizomus vinei has a high mean rate of water loss (470–4 mg g‐1 h‐1) and a low resistance to water loss (15–2 cm sec‐1); their resistance is about 10 x greater than that of a free water surface, but is about two orders of magnitude lower than that of some spiders and scorpions. Schizomus vinei excretes a clear fluid and may be ammonotelic.

Allozyme electrophoresis strongly suggests that individuals from the different caves are of the same species. Consideration of climate, age of separation of the caves and the general biology of the schizomids suggests that those caves containing schizomids may be linked.
Seasonality of reproduction in male rock elephant shrews, Elephantulus myurus
Authors: WOODALL P F. , SKINNER J D.
Published: March 2009

Male rock elephant shrews, Elephantulus myurus, showed active spermatogenesis throughout the year but had significant reductions in testis and prostate size, the proportion of interstitial cells and sperm numbers and viability from April to June, when no pregnant females were recorded. Rock elephant shrews have relatively small testes and extragonadal sperm reserves compared to many similar–sized mammals
Annual cycle of a coypu (myocastor coypus) population: male and female strategies
Authors: DONCASTER C P. , MlCOL T.
Published: March 2009

Male and female strategies were compared for wild–living populations of coypu (Myocastor coypus Molina) censused during two years in marshlands of central–west France. In a habitat composed of a canal network bisecting pasture fields typically 0–5 ha in size, coypu movements were largely restricted to stretches of open water, though males explored further from water than females. Adults occupied home ranges with a mean size of 3–82 ha or 1. 19 km of canal, males on average moving faster over a larger area and using a greater length of canal than females. Movements within partially shared ranges were most positively coordinated between male–female pairs, while male–male interactions were less frequent. Juvenile coypus were largely absent from the late winter population. Synchronization of litters in March–April resulted in a peak of juveniles in early summer. The sex ratio of juveniles and sub–adults reversed from a male bias in summer to a female bias in autumn. Population densities peaked in November at 4 ha, with a significant female bias (1M: 1–6F). In the same month, a neighbouring population at lower density (1 ha‐l after treatment with rodenticide) was significantly male biased (2–7M:lF) and may therefore have been acting as a sink for males dispersing from the high density population. Transients comprised 63% of the population. Females were resident longer than males, 22% of females remaining at least 5 months against 6% of males. Dispersal was recorded only for males aged 6 months or older. The general result, of exploratory behaviour amongst males contrasting with the establishment of longer term home ranges by females, is discussed in terms of male reproductive success and the capacity for females to influence nutrient supply to their litters.
Determination of the diet of the stone curlew (Bwhinus oedicnemus) by faecal analysis
Authors: GREEN R. E. , TYLER G. A.
Published: March 2009

The value of faecal analysis for estimating the composition of the diet of stone curlews was assessed by examination of the faeces of a captive bird fed on a measured diet. Remains of soft–bodied prey were under–represented in the faeces but the results could be adjusted to allow for this. Estimation of the size of prey was possible by measurement of remnants such as earthworm chaetae and insect mandibles. In some types of prey large specimens left more remnants than small ones and a correction was devised to allow for this. Regurgitated pellets contained large, hard remains and there was no trace of some important prey types such as earthworms. A method is described for estimating the composition of the diet of the wild stone curlews from counts of prey remains in their faeces.
Shell growth, reproduction and life cycles of Lymnaea peregra and L. palustris (Pulmonata: Basommatophora) in oligotrophic turloughs (temporary lakes) in Ireland
Authors: BYRNE R. A. , REYNOLDS J. D. , MCMAHON R. F.
Published: March 2009

The life cycles and shell growth rates of populations of the freshwater basommatophoran snails, Lymnaea palustris (Müller) and L. peregra (Miiller), were studied over a year's period in two oligotrophic turloughs (temporary lakes) in Ireland. The vast majority of individuals in these populations were annuals, though in one L. peregra and the two L. palustris populations a few rare individuals survived to a second year of life and reproductive effort. Lymnaea palustris populations were completely univoltine, while there was evidence of very limited bivoltinism in one of the L. peregra populations, the other being purely univoltine. Mean generation shell growth rates were the lowest yet reported for either species (≅ 30–35% of maximal mean shell growth rate reported for other natural populations) and were apparently the result of the low productivity and temperature, and highly variable water levels. In these species, there is a direct correlation between shell growth rates and habitat productivity. The vast majority of interpopulation growth rate variation appears to result from non–genetic ecophenotypic environmental influences. Such plasticity allows both species to grow and reproduce over a wide range of trophic conditions of which the studied turloughs represent the lower extreme. In L. peregra, oviposition was limited to spring and early summer and followed closely by near complete adult mortality. In L. palustris, adults survived through, and oviposition periods extended into late summer or early autumn. This extended adult survival and oviposition is a life history trait adaptation that allows L. palustris to survive in marginal, unstable habitats subject to periodic drying and other catastrophic perturbations. In contrast, the contracted spring oviposition of L. peregra appears to be an adaptation for life in more stable and permanent aquatic habitats as it allows newly recruited generations maximal time for pre–reproductive growth and minimizes competition with adults.
The morphology of the lung of a tropical terrestrial slug Trichotoxon copleyi (Mollusca: Gastropoda: Pulmonata): A scanning and transmission electron microscopic study
Authors: MAINA J. N.
Published: March 2009

The lung of the slug Trichotoxon copleyi is located in the body mantle where it opens to the outside through an adjustable pneumostome situated on the right side. The respiratory surface of the lung is profusely vascularized by anastomosing ‘blood’ capillaries. A thick muscular layer surrounds the gas exchange surface and may be involved in the efficient rhythmic ventilatory contraction of the lung. Externally an epithelial layer made up of large secretory cells with numerous microvilli overlies the muscular layer. The surface of the lung is made up of squamous cells with an abundance of microvilli and clustered goblet cells interspersed occasionally. The squamous cells cover the notably thin air–blood barrier which is extremely attenuated, particularly in some areas. The goblet cells contain a centrally located nucleus and numerous intracytoplasmic granules, presumably precursors of the mucus that covers the surface of the mantle cavity.

All the essential morphological prerequisites for efficient gas exchange such as an extensive surface and a thin blood–gas barrier were observed in the lung of Trichotoxon. It was concluded that this molluscan lung is structurally and functionally a true lung in all respects.
Foraging ranges and movements of jackass penguins (Spheniscus demersus) established through radio telemetry
Authors: HEATH R. G. M. , RANDALL R. M.
Published: March 2009

In order to study the movements and activities at sea of jackass penguins rearing chicks, a radio telemetry study was undertaken. Twenty five transmitters were attached to breeding adult penguins at their nest sites. These penguins were tracked for a total of 414 hours using a system of antennae on a motor–boat, the island and land–based stations. The foraging paths, foraging duration, foraging distances and swimming speeds were studied. The penguins' foraging patterns were similar; they generally left the island at night and travelled towards their foraging area, actively foraging from first light until they swam back to the island. The foraging durations and distances varied, as did the swimming speeds, according to availability of food.
Suckling behaviour and fertility in rhesus macaques (Macaca multatta)
Authors: GOMENDIO MONTSERRAT
Published: March 2009

Lactation has been proposed as the main proximate mechanism regulating female fertility among non–seasonally breeding mammals. Less is known about the effects of lactation upon fertility among seasonal species, where photoperiodic control of reproduction is widely believed to have an overriding influence. In neither case is it clear which of the different components of lactation influence fertility and in which ways. In this paper, the links between suckling patterns and the likelihood of conception during the following breeding season are examined. Data were collected at the Madingley rhesus colony, where reproduction is strictly seasonal. It is shown that fertility was depressed in lactating females when compared to non–lactating ones. Within the lactating group, mothers who suckled their infants frequently, and with a great number of independent nipple contacts in each bout, failed to conceive during the following breeding season. It is suggested that early differences in suckling patterns might reflect differences in maternal condition; and that differences during the breeding season may affect the quality of the ovulations. A considerable decrease in both the frequency of suckling and the number of nipple contacts per bout seemed to be required for conception to occur. On the other hand, neither the duration of the suckling bouts, nor the duration of the intervals between bouts, were found to be associated with the likelihood of conception.
Elastic strain energy storage in the feet of running monkeys
Authors: BENNETT M. B. , KER R. F. , ALEXANDER R. McN.
Published: March 2009

Monkeys are ‘flat–footed’ in comparison to humans, but they are still able to utilize elastic strain energy stores in their feet to reduce the metabolic energy cost of running. During contact with the ground, bending moments act on the foot to produce a ‘reversed arch’, storing strain energy which is returned in the subsequent elastic recoil. This energy–saving mechanism has been investigated in dynamic bending tests and is discussed in relation to the arched foot of humans.
Size, shell–living and carcinization in geographic populations of a hermit crab, Pagurus hirsutiusculus
Authors: BLACKSTONE NEIL W.
Published: March 2009

Carcinization, the evolution of a crab–like morphology, has occurred in many hermit crabs. Pagurus hirsutiusculus hermit crabs exhibit geographic variation in traits associated with carcinization. Measurements derived from image analysis of P. hirsutiusculus specimens from geographic locations along the Pacific coast of North America show that Alaskan specimens: (1) are larger, (2) exhibit reduced snail shell–living, and (3) have relatively broader anterior carapaces than southern Californian specimens. This geographic variation may provide general insight into carcinization and the evolution of shell loss in hermit crabs.
Analysis of the diet of the lesser horseshoe bat Rhinolophus hipposideros in the West of Ireland
Authors: MCANEY C. M. , FAIRLEY J. S.
Published: March 2009

The diet of the lesser horseshoe bat Rhinolophus hipposideros was investigated over one season by analysing faeces and discarded insect fragments collected on polythene sheets at eight roosts. Remains of 23 insect families from seven orders (Lepidoptera, Neuroptera, Trichoptera, Hymenoptera, Coleoptera, Diptera and Hemiptera) and of spiders (Araneae: Arachnida) were identified. Nematoceran Diptera were the chief prey but Lepidoptera, Trichoptera and Neuroptera were also important. Both locational and seasonal variation were demonstrated for some food categories. The predicted seasonal availability of the different insect taxa is broadly reflected in the results: the question of possible prey selection is discussed. The bat fed successfully on three families of Lepidoptera known to possess hearing organs sensitive to bat ultrasounds. The possible mechanisms by which R. hipposideros might catch such prey are reviewed.
Observations on the polyphyodont dentition of Hemiphractus proboscideus (Anura: Hylidae)
Authors: SHAW J. P.
Published: March 2009

In Hemiphractus fang–like teeth are ankylosed to the premaxilla, maxilla and prevomer, and bony odontoids are found on the dentary, angular and palatine bones. The odontoids are small, but a larger pair at the front of the lower jaw project upwards and backwards into the mouth and fit into a diastema between the anterior premaxillary teeth when the mouth is closed.

The teeth are unipartite and monocuspid, and each consists of a strongly recurved and elongated cone of orthodentine, capped at the tip by a thin layer of enamel. The inner circumpulpal layer of the dentine is tubular, but no tubules are present in the outer pallial layer. During tooth development, dentine is formed before the enamel matrix is produced, and the tooth germs lie horizontally beneath the ventral surface of each dentigerous bone. On eruption, the tooth germs migrate horizontally and become ankylosed to the outer edge of the jaw bone by a layer of cellular cementum.

During tooth replacement, the vast majority of the dentine of each tooth, and the cementum at the tooth base, are resorbed by osteoclasts. It is not clear whether the tips of the teeth are shed or not.
On the hatching and morphology of Dolops ranarum larvae (Crustacea: Branchiura)
Authors: AVENANT ANNEMARIE , VAN As J. G. , LOOTS G. C.
Published: March 2009

Fertilization and hatching of D. ranarum eggs under laboratory conditions are described. The morphology of the newly hatched larvae was studied by scanning electron microscopy and the results are compared with existing knowledge.
Correlates of sprinting, jumping and parachuting performance in the butterfly lizard, Leiolepis belliani
Authors: Losos J. B. , PAPENFUSS T. J. , MACEY J. R.
Published: March 2009

Leiolepis belliani, a cursorial, beach‐dwelling lizard, moves by running and jumping. The lizards' ability to flatten dorsoventrally, thereby increasing surface area and decreasing wing loading, may also confer parachuting ability. We measured locomotor performance of three ecologically relevant tasks: running, jumping and parachuting. In addition, we investigated whether, with the effect of size removed, locomotor performance capabilities are correlated, and whether they correlate with morphological features. Larger lizards fell and ran faster and jumped further. Lizards that were experimentally prevented from flattening fell faster than control lizards. When the effects of size were removed, limb length was uncorrelated with jumping and running performance; performance measures also were not correlated amongst themselves. The scant natural historical data available for this species suggests that lizards do not use their parachuting capability, and that dorsoventral flattening may have evolved for some other purpose. Leiolepis might serve as a useful model in understanding the evolution of gliding lizards (e.g. Draco).
A quantitative theory of expected volume changes of the mouth during feeding in teleost fishes
Authors: MULLER M.
Published: March 2009

The mechanism of mouth expansion in fish, consisting of jaws, suspensoria (j) and hyoids (h) has been modelled by a four‐bar isosceles linkage. This model provides insight into limitations and demands of the expansion system used in feeding, as it can be optimized with regard to maximum mouth volume increase. The optimum length ratio of hyoids and jaws was found to be h/j = 0–7. This optimum is modified by mouth bottom depression, jaw protrusion and swimming.

To expand the mouth, at least two forces are required; one exerted by the sternohyoid and ventral body muscles, the other by the epaxial muscles through transmission in the quadrato‐articular joints. (Data from EMG experiments confirm the synchronous activity of these muscle groups.) Force transmission and mouth volume increase are constraining quantities, which can be compromised. This leads to a model of the initial mouth shape which is actually found in many ‘generalized’ fishes, and to demands concerning volume and physiological cross‐sectional area of the muscles involved.

Options for specific relative lengths of jaws and hyoids (h/j‐ratios) are, for various fish species, compared with model predictions. The applicability of the model approach is shown by the obtained results.
Ungual asymmetry in the context of pedal symmetry in Ailuronyx (Reptilia Gekkonidae): modification for an opposable grip
Authors: RUSSELL A. P. , BAUER A. M.
Published: March 2009

The claws of the gekkonine gecko genus Ailuronyx are unique in being asymmetrically disposed. Those of digits I‐III are curved towards the body, whereas those of digits IV and V curve away from the body. This ungual asymmetry is imposed upon the essentially symmetrical pedal morphology that typifies pad‐bearing geckos. The resultant functional organization of manus and pes parallels that seen in chameleons. The pedal configuration of Ailuronyx seychellensis appears to provide a mechanical advantage for locomotion on at least some of the animal's natural substrata.
The larval and post‐larval development of Percnon gibbesi (Crustacea, Brachyura, Grapsidae) and the identity of the larval genus Pluteocaris
Authors: PAULA J. , HARTNOLL R. G.
Published: March 2009

The larval and post‐larval development of Percnon gibbesi, from a combination of laboratory‐reared and plankton‐caught material, is described, and larval characters within the Plagusiinae are discussed. The synonymy of Percnon and Pluteocaris is established.
Opportunistic foraging by three species of cormorants in an Australian estuary
Authors: TRAYLER K. M. , BROTHERS D. J. , WOOLLER R. D. , POTTER I. C.
Published: March 2009

Aspects of the feeding biology of three species of cormorant (Phalacrocorax melanoleucos, P. sulcirostris and P. varius) were investigated in the large Peel‐Harvey Estuary in south‐western Australia in April and October 1986 and January 1987. The duration of dives by each species increased with depth and at each depth was greater in P. varius than in the two smaller species. Differences in the ranges of depths in which the similarly sized P. melanoleucos and P. sulcirostris fed would have reduced any potential interspecific competition for feeding space and food. The dive‐rest ratio was similar (2.6–2.8) in all three species. Comparisons between the diet of each cormorant species and the potential prey where foraging occurred demonstrated that all three cormorant species were opportunistic feeders, ingesting predominantly small, slow‐swimming, benthic‐feeding fish and crustaceans. The small size of the prey was limited by the small dimensions of the gullet. There was no evidence that any of the three cormorant species were likely to exert a pronounced adverse effect on the abundance of the major commercial fish in the estuary or on the food of these teleosts.
Light and electron microscope studies on ovarian follicles in the lizard Chalcides ocellatus
Authors: IBRAHIM M. M. , WILSON I. B.
Published: March 2009

The development of ovarian follicles in a skink has been studied with light and electron microscopy. In early stages the previtellogenic oocyte has a follicular covering (granulosa) comprising only two cell types, small cells and pyriform cells. A complex microvillous interdigitation between follicle cells and oocyte is present from very early stages but regresses as a mature size is reached. The outer thecal layer differentiates into distinct interna and externa as growth proceeds. Occasional biovular follicles are formed. Pyriform cells establish direct continuity with the oocyte via cytoplasmic bridges which traverse the layer of microvilli interdigitating in the zona pellucida. Such bridges appear most frequently just before the onset of yolk deposition; the organelles and cytoplasmic constituents presumed to be transferred across them may stimulate this activity. As the follicles grow, the pyriform cells shrink and disappear to leave just the small cells forming the single layered granulosa. There is asynchrony in recruitment and/or early growth rates of follicle crops and uniformity of oocyte size appears only as vitellogenesis nears completion (with up to five oocytes, about 1 cm in diameter, on each side). Yolk deposition may involve transformation of golgi vesicles or pinocytotic vesicles but there is no evidence to show mitochondria as foci for deposition.
Burrowing dynamics and energy cost of transport in the soft‐bodied marine invertebrates Polyphysia crassa and Priapulus caudatus
Authors: HUNTER R. DOUGLAS , ELDER H. Y.
Published: March 2009

The dynamics and mechanical forces generated during burrowing in Polyphysia crassa (Annelida: Polychaeta) and Priapulus caudatus (Priapulida) were investigated. Both animals live in soft marine muds and burrow by utilizing a direct peristaltic wave alternating with a high internal pressure event which thrusts the anterior part of the body into the substratum. Forces generated during the various phases of a typical burrowing cycle were measured in animals moving beneath the natural substratum at 5±3 °C using electronic transducers and recorder. During ‘head’ advance Polyphysia generated 0.027 N, and during ‘tail’ advance 0.020 N, with peak internal pressures averaging 0.95 kPa (= 0.095 N/cm2). Force by Priapulus during head advance and tail advance was 0.081 N and 0.121 N, respectively, with peak internal pressures averaging 2.47 kPa (= 0.247 N/cm2). Polyphysia moves more slowly (0.24 cm/min) than does Priapulus (0.76 cm/min) and expends more energy on mass moved per unit distance. These force measurements during a burrowing cycle were used in place of respirometry as a basis for computation of net cost of transport (NCT) for each animal. NCT for Polyphysia was 635 J kg‐1 m‐1 and for Priapulus was 314Jkg‐1m‐l. Cost of transport for all burrowing animals thus far investigated is high compared to swimming, running and flying. For soft‐bodied invertebrates that live an entirely buried existence this high cost must be interpreted in the broader context of the adaptive value of infaunal life, especially protection against predation, and not as simply a means of moving about.
The annual cycle in body weight of small mammals from the Transvaal, South Africa, as an adaptation to a subtropical seasonal environment
Authors: KORN HORST
Published: March 2009

Seasonal breeding of non‐hibernating small mammals is generally associated with a reduction in body weight during the non‐breeding period. In aseasonal breeders and in exceptional situations, when winter breeding occurs, this pattern cannot be found.

The reduction in body weight is thought to be a means to reduce energy requirements during the harsh non‐breeding season that can either be winter, in the Holarctic, or the dry season in the Transvaal highveld.

The controlling mechanism in the strongly seasonal subtropical environment in southern Africa seems to be photoperiod as in small mammals from the northern hemisphere.

Since a general agreement in body weight changes was found in rodents and shrews from both areas, further similarities in adaptations to strongly seasonal environments in the subtropics are expected.

For the first time it is shown that the adaptive responses of small mammals to unfavourable seasons are similar in the Holarctic and seasonal subtropical areas.
The West African species of Bathygobius (Teleostei: Gobiidae) and their affinities
Authors: MILLER P. J. , SMITH R. MCK.
Published: March 2009

The circumtropical gobiid fish genus Bathygobius Bleeker, 1878 is discussed and defined in terms of external features, including the head lateral‐line system, and osteology. Three West African species are recognized and redescribed: the amphiatlantic B. soporalor (Valenciennes, 1837) and two endemics, B. burtoni (O'Shaughnessy, 1875) and B. casamancus (Rochebrune, 1880). West African B. soporator differs significantly from western Atlantic material only in average values for predorsal scales and some body proportions, so that separation of eastern and western Atlantic populations as morphological species is not warranted. The affinities of the West African Bathygobius species are examined by means of phenetic (presence‐only group‐average clustering) and cladistic (Camin‐Sokal, Dollo and Wagner) numerical processing of a binary database comprising 46 character states in 15 Operational Taxonomic Units (OTUs) formed by species of Bathygobius. Results do not indicate close common ancestry between the West African endemic species and B. soporator, which has probably colonized West Africa from the New World. The implications of various cladistic schemes for the relationships of certain other American species are also noted.