bluuebunny/crossref_metadata_2025 huggingface dataset:
Visible variation in the dog‐whelk, Nucella lapillus
Authors: Berry R. J. , Crothers J. H.
Published: August 2009

Shell shape and colour variation is common in littoral molluscs. As far as shape is concerned, exposure to wave action acts as a strong agent of natural selection, but only speculation seems to have been directed towards elucidating the determinants of colour variation. In the dog‐whelk (Nucella lapillus (L.)) diet may play some part in producing the pigment for colour. However white and banded forms are often found in otherwise coloured colonies. This study describes the classification for colour and banding of 83,524 whelks from 444 areas around the British Isles and west Atlantic coast. Colour and banding were significantly correlated r=0.45±0.05). Because of the possible involvement of diet in shell colour, attention has been confined to banded forms. No obvious pattern in distribution could be discerned. Possible factors affecting the occurrence and incidence of banding are: climate; geology; exposure to wave action; predation; intra‐ or interspecific competition; cryptic genetical factors; or intraspecific recognition. The only one which was definitely associated with banding frequency was exposure (r= 0.33±0.05), but there were so many exceptions to the correlation (e.g. highly exposed populations which were entirely unhanded), that this is unlikely to be causal. The most probable explanation seems to be the local spread of mutant forms (probably linked to fitness traits), which have not attained equilibrium frequencies–even though N. lapillus has apparently occurred in large colonies round much of the British coast since the end of the Pleistocene.
The development of the thyroid glands in anuran amphibians of Iraq*
Authors: Michael M. I. , Adhami M. A. Al
Published: August 2009

The development of the thyroid gland was studied in various larval and metamorphic stages of three Iraqi anurans of the genera Bufo, Hyla and Rana. At comparable stages of development, differentiation of the gland occurs earlier in the last two genera than in Bufo. It is suggested that the development of the thyroid during prometamorphosis is closely related to the histogenesis of the pronephric system in these genera.
Field mice (Apodemus sylvatkus) on the Castle Rock, Edinburgh: an isolated population
Authors: Berry R. J. , Warwick T.
Published: August 2009

Long‐tailed field mice (Apodemus sylvatkus) live on the Castle Rock in the centre of Edinburgh city, which has been cut off from open country for nearly one and a half centuries. However they do not differ significantly from mice caught 4 km away on the edge of Edinburgh. The Edinburgh samples have different frequencies in 5 out of 20 nonmedical skull variants when compared with a Durham sample, and in eight when compared with a Perthshire one. The most likely explanation for the lack of differentiation of the Castle Rock sample is that it is a relic of a population once continuous with the main breeding population of Britain, that has survived in its restricted area despite its small numbers.
Extraspecific imposition of social grouping among surgeonfishes (Pisces: Acanthuridae)
Authors: Barlow George W.
Published: August 2009

The Manini is a widely distributed surgeonfish that is often abundant on reefs. It has two modes of existence, scattered individuals or dense column‐forming schools, which may be seen on the same day at different places on the reef. In Hawaii schooling is a tactic used for getting to the bottom to feed when the bottom is held by territory‐holding food competitors. Mixed‐species “flocks” are an extension of this tactic. In atoll situations habitat partitioning exists, with the Maninis feeding in the intertidal area away from competitors; there, schooling is anti‐predator behaviour.
Structure and keratinization of the skin of a fresh‐water teleost Notopterus notopterus (Notopteridae, Pisces)*
Authors: Mittal A. K. , Banerjee T. K.
Published: August 2009

The microanatomy of the skin of an air‐breathing fish, Notopterus notopterus is described and related to the distribution of various histochemical constituents involved in keratinization.

In addition to distinct unicellular mucous glands, secreting sulphated acid mucopolysaccharides, the epidermis of TV. notopterus is mainly composed of polygonal cells containing sulphated acid mucopolysaccharides, concentrated in the distal peripheral areas of the cells. The mucopolysaccharide contents of these polygonal cells gradually increase as they mature and move towards the outer surface. They may ultimately form a part of the protective keratinized layer.

The mature keratinized cells give positive reactions with Papanicolaou's stain, contain cystine bound SS groups, cysteine bound SH groups, calcium and moderate amounts of sulphated acid mucopolysaccharides. These cells having flat pyknotic nuclei undergoing karyolysis, are fused together at their lateral margins to form an intact sheet which is frequently seen sloughing off from the underlying epidermal cells.

The process of cornification in N. notopterus is comparable to that of the amphibians and the aquatic reptile–the turtle.

There exists a well developed lymphatic system in between the cells of the stratum germinativum having lymphatic spaces often penetrating deep into the middle layer. This is an adaptation which contributes largely to the protective function of the fish skin.

The layers between the scales and the basement membrane contain sulphated acid mucopolysaccharides. This together with keratinization has been correlated with the peculiar mode of life of the fish, often facing the problems of desiccation.

The epidermis is anchored on the dermis by fine strands of collagen fibres connecting the basement membrane and the scales, and by numerous fine papilla‐like projections of the basement membrane projecting in between the cells of the stratum germinativum.

Numerous fine elastic fibres in the connective tissue pockets in which scales are lodged, provide for free movement of the scales when the body of the fish is bent during swimming.

Pit organs singly or in groups are found distributed in the epidermis.
The development, growth and degeneration of the pronephric system in anuran amphibians of Iraq*
Authors: Michael M. I. , Yacob A. Y.
Published: August 2009

The growth and degeneration of the pronephric system were examined at different larval and metamorphic stages in Bufo viridis viridis, Hyla arborea savignyi and Rana ridibunda ridibunda. It was found that the process of degeneration is sequentially similar to that of differentiation being in a cranio‐caudal order in the last two genera, but in the opposite direction in the genus Bufo. It is concluded that in these genera pronephric degeneration is closely related to the histology of the thyroid glands.
Predation of incubator birds (Megapodius freycinet) by Komodo dragons (Varanus komodoensis)
Authors: Lincoln G. A.
Published: August 2009

A short study was made of the nesting habits of a species of megapode, Megapodius freycinet on the island of Komodo. The birds were found to build giant nesting mounds (0.95 × 7.15 m) in scrub and woodland close to the seashore or alongside river beds; 23 active and 19 abandoned mounds were located in an area of 250 ha.

The mounds were apparently added to from year to year, and consisted of dry sand and soil, plus leaves and sticks in most cases. The upper parts of the mounds were invariably exposed to the direct rays of the sun; the temperature within the active mounds was 33–37° C and slightly less in mounds not in use by the birds. According to the local people the nesting season of the megapodes extended from late August to November, and the chicks were hatched before the arrival of the rains in December. Up to four eggs had been recovered from a single mound.

The active mounds were all spaced apart by at least a 100 m, and the closest ones were usually separated by a river bed. This pattern suggested the species was territorial. One or two birds were often seen scraping at a mound or feeding close by, and their behaviour was recorded.

The Komodo dragon, Varanus komodoensis, was a frequent visitor to the nesting mounds of the megapodes, and was able to burrow into them and steal the eggs.
A multidisciplinary approach to a new species of Gobius (Teleostei: Gobiidea) from southern Cornwall
Authors: Miller P. J. , El‐tawil M. Y.
Published: August 2009

The Mediterranean‐Atlantic genus Gobius L. (type G. niger L.) is redefined with listing and comparison of the 14 species currently assigned to it. A G. auratus complex of species is discussed with special reference to the real identity of the former species originated by Risso. Features of a further new species, Gobius couchi, from Helford, Cornwall, and Lough Ine, Co. Cork, are compared with those of its nearest relatives, G. auratus Risso, 1810, G. luteus Kolombatovic, 1891, and another new offshore form from the English Channel.

A systematic description of G. couchi is given, including details of head lateral‐line canals and sensory papillae, and also of the karyotype (Appendix). A summary of biology covers geographical distribution, habitat and associated intertidal fishes, diet, parasites, reproduction, age‐composition, and size. The electrophoretic properties of selected functional proteins (haemoglobins, muscle‐myogens, and lactate‐dehydrogenase isozymes) are described and contrasted with those in other available neighbouring species (G. paganellus, G. niger, and Thorogobius ephippiatus). Alternative terminology for LDH patterns is discussed, and the role of protein studies considered for gobioid classification.

The specific status of G. couchi relative to the Mediterranean G. auratus is reviewed, and meristic divergence between the two compared with that found among widely separated populations of G. niger which exhibit less geographical variation in these criteria. Mechanisms for allopatric speciation are discussed, and it is concluded that ancestral populations of the two forms became parted possibly at the time of the Roman regression (corresponding to the Mindel glaciation) when the Mediterranean may have been closed‐off from the Atlantic. Rates of evolution shown by European gobiids are considered in the light of Pleistocene and postglacial opportunities for reproductive isolation.
Dental polymorphism and systematics in Saccodon, a neotropical genus of freshwater fishes (Parodontidae, Characoidei)
Authors: Roberts Tyson R.
Published: August 2009

Population samples of algae‐grazing, mountain stream characins of the genus Saccodon of Panama and northwestern South America are reported with up to four sharply differentiated dental morphs. The morphs differ strikingly in the form and numbers of functional teeth and of preformed replacement teeth. Recognition of the polymorphic nature of these variations necessitates new concepts of taxa at species and generic levels. Two species with similar polymorphism are involved, Saccodon dariensis from Panamá and Colombia, and Saccodon wagneri from the Guayas basin on the Pacific coast of Ecuador. A total of rive morphs have been discovered, three of which are homologous in the two species.
The genitalia and accessory glands of the pseudoscorpion Cheiridium museorum (Cheiridiidae)
Authors: Legg Gerald
Published: August 2009

The genitalia of the male Cheiridium museorum Leach consists of a cup‐shaped ejaculatory canal atrium which opens into a simple saccate genital atrium. Associated with the genital atrium are a number of thickened regions of the cuticle: the dorsal apodeme, lateral apodemes and lateral rods. These both support the genital atrium and provide regions for muscle attachment. Two pairs of accessory glands, anterior and posterior dorsal glands, are present.

The genital atrium of the female is divided into a median and two lateral diverticula. Lateral apodemes are present, as are two sets of accessory glands, lateral and median glands.

The possible function of the genitalia of the male is considered.
Field studies of the diet of Rhabdosargus holubi (Pisces: Teleostei: Sparidae)
Authors: Blaber Stephen J. M.
Published: August 2009

Rhabdosargus holubi is a marine teleost endemic to south east Africa. The juveniles occur mainly in estuaries but the adults are largely confined to the sea. Stomach contents of over 2000 juvenile R. holubi were examined from fish captured in the open Kowie and Msikaba estuaries, and from the closed West Kleinemond and Kasouga estuaries. Juvenile R. holubi feed mainly on aquatic vegetation. The fish cannot, however, digest the vegetation eaten due to the absence of a cellulase or a method of breaking up the plant tissue. Therefore, the plant material is passed out in an undigested state. Epiphytic diatoms and sessile ectoprocts (Bryozoa) are, however, removed from the macrophytes or multicellular algae in the stomach, and are subject to digestion. Diatoms may form up to 50% of the dry weight of the plants consumed. A variety of animals was also eaten. Maximum total food consumption was estimated at 1·9% of body weight per day although this is probably an underestimate. Feeding only took place during daylight hours. The teeth of juvenile R. holubi are specialized for grazing aquatic plants and differ from those of adult R. holubi. Adults consume mainly bivalves and large crustaceans. It is suggested that the different food requirements of the adults and juveniles determine at what stage this species enters and leaves estuaries.
Observations on the ciliary feeding mechanism of the brachiopod Crania anomala
Authors: Chuang Shou‐Hwa
Published: August 2009

In young Crania anomala with a trocholophe or an early schizolophe one inhalant current enters the anterior gape, filters past the single bell‐shaped cirrous basket and spills out diffusely as exhalant current both anteriorly and laterally. Late schizolophe or early spirolophe forms two separate cirrous baskets which produce two separate inhalant currents: the exhalant current still diffuses out anteriorly and laterally. In later stages either one single exhalant current comes out at the anteromedial region, or three exhalant currents, including an additional one at each posterolateral region.

The roof of the visceral cavity is attached in five places to the dorsal valve of Crania to form a mantle recess, an anterior passage and two lateral passages. A hole bored through the dorsal valve into the mantle recess or the anterior passage lets out exhalant current. The palaeobiological significance of this lies in the possible use of the hole in the perforate shell valve of the siphonotretid fossil inarticulate Schizambon australis as an exhalant opening. In this species the hole leads into the mantle recess, which also communicates via a lateral passage with each posterolateral part of the mantle space.
Coat colour inheritance in Soay, Orkney and Shetland sheep
Authors: Ryder M. L. , Land R. B. , Ditchburn R.
Published: August 2009

Analysis of the numerical proportions of Soay, Orkney and Shetland sheep of different colours together with test matings, produced results compatible with the hypothesis that these breeds have a multiple allelic series at locus A, white (A1) being dominant to grey (A2) and both being dominant to the gene for self‐colour (A5). The alleles at the A locus are epistatic to the alleles for pigment production at locus B, black (B1) being dominant to brown (B2).
Allometric growth in the Praying mantis Stagmatoptera biocellata
Authors: Rodriguez Ernesto , Maldonado Héctor
Published: August 2009

The growth of ten exoskeletal structures has been studied throughout the post‐embryonic development in Stagmatoptera biocellata. The selection of an appropriate statistical procedure to analyse the data was discussed. In spite of theoretical prediction the least‐squares regression technique turned out to be as efficient as the Bartlett (1949) procedure for studying growth. Longitudinal treatment of longitudinal data proved to be the best method for this kind of analysis. All the dimensions investigated showed some statistically significant degree of allometric growth and could be ascribed to certain class of allometry. The adaptative value of some allometric growth patterns was discussed in terms of physiological efficiency. A hypothesis put forth by Balderrama & Maldonado (1973) about the anatomic relationships between the parts involved in the mantis strike, received clear support from this analysis. A quantitative assessment of Dyar's (1890) and Przibram's (1912) rules and their modifications led us to conclude that they are untenable at least for the mantid Stagmatoptera biocellata. However, some periods of constant growth ratio could be identified during the post‐embryonic development and the concept of maximum growth period was put forward as a complementary element for typifying structures.
Observations on the biology of Apatopygus recens (Echinoidea: Cassiduloida) around New Zealand
Authors: HIGGINS R. C.
Published: August 2009

The biology of the New Zealand cassiduloid echinoid Apatopygus recens is reviewed in terms of its geographical distribution, sediment relationships, and associations with other echinoids. Observations were also made on the density and size‐frequency distribution of an A. recens population at Croisilles* Harbour, Tasman Bay, and on the burrowing and feeding behaviour of specimens from this locality in an aquarium.

A. recens is a rapid and continuous deposit feeder which burrows completely beneath the surface of the coarse sediments with which it is characteristically associated. The construction of a respiratory burrow to the sediment surface was not observed and the species appears to rely entirely on an adequate interstitial water flow for its respiratory requirements. Two 24 mm long specimens each defaecated an average of 0·76 g dry wt of sediment/h which at the Croisilles Harbour habitat was equivalent to a population ingestion rate of about 7·6 g dry wt of sediment/m2/h.
Cell junctions acting as intestinal valves in nematodes
Authors: Seymour Malcolm K. , Shepherd Audrey M.
Published: August 2009

Serial sections of the rectal valve in Aphelenchoides blastophthorus Franklin and the oesophago‐intestinal valve in Thornenema wickeni Yeates were examined electron microscopically. Each valve when closed appears as a convoluted path of closely apposed (10 nm) pairs of three‐layered cell membranes. Both valves serve to stop intestinal leakage, open briefly and rapidly by forcible dilatation and are closed by pressure from surrounding tissues, helped perhaps by intermolecular forces.
Mating and spawning of the crayfish Austropotamobius pallipes (Crustacea: Astacidae)
Authors: Ingle R. W. , Thomas W.
Published: August 2009

Mating and spawning of the crayfish Austropotamobius pallipes (Lereboullet) is described and compared with the accounts of this behaviour in Orconectes limnosus, Pacifastacus trowbridgii and Homarus amerieanus.
The Nuffield Unit of Tropical Animal Ecology (1961–1971)
Authors: Beadle L. C.
Published: August 2009

Synopsis. This article has been composed at the request of the Committee of the Nuffield Unit of Tropical Animal Ecology (NUTAE) at its final meeting in Cambridge in October 1971 and has benefited from the comments of the Committee Members and the two successive directors. It is a short record of the history and aims of the Unit and includes only a superficial review of the research done, though a full list of publications is appended. It refers to the ten years ending in 1971 during which it was basically financed by the Nuffield Foundation and after which it was transferred to the Uganda Institute of Ecology. For an account of the previous development of interest in conservation and research on African wildlife see Worthington, E. B. (1961). The wild resources of East and Central Africa. London. H.M.S.O.
Effects of group stability, male‐male aggression, and male courtship behaviour on environmentally‐induced ovarian recrudescence in the lizard Anolis carolinensis
Authors: Crews David
Published: August 2009

Reproductively inactive, winter dormant female Anolis carolinensis were exposed to a stimulatory environmental regime while in socially stable or unstable male‐female groups. In a second experiment, winter dormant females were exposed to varying amounts of male courtship and male‐male aggression. Results indicate that (1) the presence of a stable dominance hierarchy among group males is necessary for male facilitation of environmentally‐induced ovarian recrudescence (OR) (an unstable dominance hierarchy inhibits OR), (2) the behaviour patterns responsible for the facilitation and inhibition of environmentally‐induced OR are courtship and male‐male aggression, respectively, and (3) ovarian development is graded in accordance to the amount of male courtship to which the female is exposed. It is proposed that male courtship insures normal gonadotropin (GT) secretion while the absence of male courtship results in subnormal GT secretion and the presence of male‐male aggression suppresses environmentally‐induced GT secretions. The functional significance of the inhibition of environmentally‐induced OR by male‐male aggression and its possible relation to differential vernal emergence in temperate‐zone reptiles is discussed.
Chemical conditioning of the environment by the freshwater pulmonate snails (Biomphalaria glabrata) and its effect on growth and natality rates
Authors: Thomas J. D. , Goldsworthy G. J. , Benjamin M.
Published: August 2009

The effects of heterotypically conditioned media on the growth and natality rates of Biomphalaria glabrata have been studied under conditions which prevented the assay snails from being stimulated by tactile and visual signals from other snails. It was demonstrated that increasing the density of snails producing the conditioned medium up to a critical threshold resulted in enhancement of growth and natality rates. Further increases in density beyond the optimum level caused a reduction in growth and natality rates. Possible explanations for these effects, which were caused by chemical conditioning, are discussed.
An investigation of the surface of the cuticle and associated sensory structures of the terrestrial isopod, Porcellio scaber
Authors: Holdich D. M. , Lincoln Roger J.
Published: August 2009

The exoskeletal surface of the body of the terrestrial isopod, Porcellio scaber has been examined with the scanning electron microscope as part of a study of the structural changes associated with the transition from sea to land in the Isopoda. No sexual differences are apparent. The dorsal cuticular surface is characterized by large tubercles, minute plaques and pits, separated by amorphous areas. Apart from the eyes the only structures of apparent sensory function are relatively large setae which occur near the antero‐lateral and posterolateral edges of each epimeron, and sensilla squamiformia (tricorns). Tricorns are extremely numerous on the dorsal surface and appear to be formed from the fusion of a plaque and a sensillum which arises from a pit. Much of the ventral body surface is covered with closely‐set plaques, tricorns being restricted to the epimera. Along the sides of the mid‐ventral sternal groove occur numerous small tubercles each surmounted by a single seta. Similar, though smaller structures are found in a single row along the outer edge of the epimera. The water capillary system of this species is formed from spines which arise from plaques around the pereopodal sockets and along the junctions between the epimera and sternites. Most of the sensilla described appear to be mechanosensory and are probably associated with the thigmokinetic and proprioceptive responses of the woodlouse.
On the spatial distribution, feeding and reproduction of the vermetid gastropod Dendropoma maximum
Authors: Hughes Roger N. , Lewis A. H.
Published: August 2009

D. maximum is a dominant species of outer reef flats in the Red Sea, reaching densities of about 22/m2 and biomass of 15.8 g dry tissue/m2. A few individuals attached to loose rocks are found inside the breaker zone but they may have been dislodged by heavy seas from the outer reef flat. D. maximum feeds from a mucus net which is spread by wave action over the substratum. Hauling the net occurs at approximately 13 minute intervals throughout the 24 hours and lasts about two minutes. Neighbours with overlapping nets stimulate each other to haul and reduce feeding efficiency. The net is grasped by a pair of lateral jaws, tugged free of the substratum by rotation of the body and ingested by a zipper‐like action of the lateral and marginal radula teeth. The robust, central and lateral teeth become worn, possibly while channelling out the substratum to accommodate new shell. Defaecation occurs about 2.4 times an hour, amounting to 10450 kcal/m2/y. Females may brood simultaneously at least 11 egg capsules at various stages of development, which are suspended by stalks from the roof of the shell and pass through a dorsal slit in the mantle. Each capsule contains–500 embryos which develop into larvae with simple, coiled shells 0.33 mm in diameter. There is no planktonic phase. Adult shells amount to 2.5 kg/m2 on the outer reef flat, while dead shells are often occupied by blennies. Although D. maximum is not a specialized filter feeder, the highly developed ciliary mechanisms suggest that filtering may be an auxiliary feeding method.
An integrated classification for polymorphism and sexual dimorphism in butterflies
Authors: Vane‐Wright R. I.
Published: August 2009

In bisexual organisms, pattern polymorphism may affect both sexes equally (unimodal polymorphism), or be expressed differently in the two sexes (bimodal polymorphism). Bimodal species may or may not have one or more forms that are identical in both sexes (shared morphs), in addition to those pattern forms which only occur in a particular sex (sex‐limited morphs). Sex‐limited morphs may occur in the male sex only, the female sex only, or be found in both sexes. Bimodal species in which there are no shared morphs show complete sex‐limitation of pattern (dualism), in contrast to those in which there are shared morphs, which may be said to exhibit partial sex‐limitation. Sexual dimorphism is here divided into two categories, partial sexual dimorphism (where both similar and dissimilar prospective pairs coexist), and complete sexual dimorphism (where only dissimilar prospective pairs coexist). From these considerations a comprehensive classification of nine categories of phaneromorphic polymorphism is developed, including monomorphism as the limiting case. This classification is presented graphically for convenient reference and visualisation. Selected examples of each class as they occur in butterflies are given, for both mimetic and non‐mimetic species. The necessity for such a classification as a tool in the study of the evolution of polymorphism, sexual dimorphism and mimicry in butterflies is briefly discussed. This classification should also prove relevant to polymorphism studies in all non‐parthenogenetic, bisexually reproducing species of organisms.
Regulation of avian eggshell porosity
Authors: Tullett S. G.
Published: August 2009

Pores and mammillae per unit area of the eggshells of 34 avian species were counted. The number of pores/cm2 varied from about 45 for the King penguin (Aptenodytes patagonia) to 306 for the Japanese quail (Coturnix coturnix). Throughout this range there was a positive linear correlation (r=0.92) between the number of pores and the number of mammillae per unit area of shell.

Scanning electron micrographs of the inner surface of eggshells scoured with NaOH suggested that the above relationship may result from the packing of the calcite columns, which is controlled by the density of the mammillary seeding sites laid down upon the outer shell membrane. Thus it is inferred that the distribution in the uterus of the cells which secrete the sites on which calcification is initiated determine ultimately the porosity of the eggshell. Such a concept implies that evolutionary pressures operate primarily upon these cells rather than on crystallisation, a process over which a bird may have no control.
Bird counts either side of Wallace's Line
Authors: Lincoln G. A.
Published: August 2009

Bird counts were made on the islands of Java, Bali, Lombok and Sumbawa during a 16 day study in September 1973 in order to compare bird populations either side of Wallace's Line (running between Bali and Lombok). Evidence was collected which showed that the two westerly islands of Java and Bali share a relatively similar bird fauna, but this differs noticeably from the bird life found more to the east. The conspicuous faunal break which occurs between Bali and Lombok appears to represent a transition from a rich fauna associated with the large continental island of Java, to a somewhat impoverished fauna of the outlying oceanic islands. Marked differences in habitat on the four islands were considered to be primarily important in dictating this change.

Using frequency and abundance estimates for the different bird families it was shown that Java and Bali have a preponderance of Oriental (Asian) birds while Lombok and Sumbawa have more conspicuous Australian elements. However, when the presence or absence of species or families alone are considered all four islands have more Oriental types. It seems that a small range of Australian species including honey eaters, wood swallows, zebra finches and parrots are relatively abundant on Lombok and Sumbawa, and are a sufficiently conspicuous feature of the fauna east of Wallace's Line to impress the visitor that he has entered Australasia.

The bird counts illustrate some of the changes originally described by A. R. Wallace (1860).
The length and diameter of the coat fibres of the Musk ox
Authors: Wilkinson Paul F.
Published: August 2009

The length and diameter of underwool and outer hairs from captive and selectively‐bred Musk oxen were measured. Considerable variation was found between animals and some of its sources were isolated and discussed. Finally, the underwool was compared briefly with other wool fibres, and some implications of the data for studies of prehistoric animal domestication were discussed.
The morphology of the mammalian cervical pleurapophysis
Authors: Cave A. J. E.
Published: August 2009

Current osteological literature manifests an unacceptable lack of uniformity in the topographical definition of the mammalian cervical pleurapophysis. Definitions advanced are inadequate or erroneous or even mutually contradictory. A new and corrective definition of the cervical pleurapophysis is therefore propounded satisfactory to the phylogenetic and morphological requirement of vertebral serial homology.
Islands and the evolution of Microtus arvalis (Microtinae)
Authors: Berry R. J. , Rose F. E. N.
Published: August 2009

The widespread European vole species Microtus arvalis (Pallas) occurs in the British Isles only on Guernsey and various of the Orkney islands. The traditional explanation for this peculiar distribution has been that the island races are the sole relicts of a previously cosmopolitan form. This idea is not supported by the present study, in which population samples are compared with voles from a number of localities from Continental Europe. Using the frequencies of non‐metrical skull variants as genetical markers, it emerged that although the Guernsey population (Microtus arvalis sarnius) was virtually indistinguishable from typical German specimens, and therefore likely to be a relict from the time when Guernsey was connected to France, the Orkney populations (Microtus arvalis orcadensis) formed a distinct group with affinities more to south Europe than elsewhere. It seems probable that arvalis was brought to Orkney by some of the earliest human colonizers about 4000 years ago, and then radiated to the different islands. It is argued that this manner of peripheral differentiation may be an important method of evolutionary change.
Age‐structure and life‐span in the Common goby, Pomatoschistus microps
Authors: Miller P. J.
Published: August 2009

Age‐structure and longevity in the euryhaline Common goby, Pomatoschistus microps (Krøyer), has been studied by monthly sampling of estuarine and shore populations in the Isle of Man and in collections from other parts of the British Isles. Age of individuals was determined by examination of caudal peduncle scales, where time of annulus formation was confirmed from monthly changes in mean terminal sclerite width and in frequency of scale‐types. After the first winter of life, an annulus of narrow sclerites is produced on resumption of growth in spring and a separate summer annulus, corresponding with a growth retardation during the peak breeding season, is laid down usually in June. Maximum age did not exceed 21–26 months, with most adult fishes dying in the second autumn of life a few months after their first breeding season (within possible age‐limits of 12–20 months). Seasonal migration is discussed with reference to the downstream movement of estuarine P. microps when sexually mature after the first winter of life, the winter distribution relative to temperature, and the preference of newly demersal young for less saline parts of the estuary. Cases of mortality from predation and environmental extremes are listed. The question of senescence in relation to life‐history pattern and survival in P. microps and some other teleosts is discussed with special reference to gonad maturation and spawning, and the attainment of limiting size.
The food of weasels (Mustela nivalis) on farmland in north‐east Scotland
Authors: Moors P. J.
Published: August 2009

Little is known of the foods of weasels (Mustela nivalis) in farmland in Scotland. Data on their diet were collected from two such areas in east Aberdeenshire between 1971 and 1973. A total of 264 samples of scats were analysed, including 236 from live‐trapped weasels, and the gut contents from 82 weasel carcasses were also examined. Small rodents, particularly Microtus, were the principal prey, but lagomorphs, birds and insectivores were also eaten. Seasonal variations in the diet were influenced by the availability of prey. Weasels ate very few Clethrionomys although they were common on one study area. Significantly more lagomorphs were identified in scats collected in the morning than in the evening, but no such differences were found for other prey.
Observations on the morphology of Echinocardium cordatum (Echinoidea: Spatangoida) from diverse geographical areas
Authors: Higgins R. C.
Published: August 2009

Various test features in six specimens of Echinocardium cordatum collected from South Africa, Trindade Island (South Atlantic), Australia, Japan and Ireland were compared with previously established data relating to British and New Zealand specimens. Morphological variations between the specimens were interpreted as infra‐specific differences and no evidence was detected that the spatangoid conventionally defined as E. cordatum is more than a single species throughout its extensive geographical range.
Umbonium vestiarium, a filter‐feeding trochid
Authors: Fretter Vera
Published: August 2009

U. vestiarium, a dominant species on the seaward side of sand flats at the mouth of the River Vellar, S. India, collects food by filtering the palliai stream of water as it glides over the surface of the sand or is buried except for its tentacles, eye stalks and siphons. It may remain stationary or creep when buried, but feeds only when conditions are quiet. Inhalant and exhalant siphons are formed by folding of the neck lobes of the epipodium; elsewhere the entrance to the mantle cavity is blocked by the head. The inhalant current is filtered by siphonal tentacles and then passes over the osphradium which encircles the base of the siphon. The gill is monopectinate with the axis, which is fused to the mantle throughout its length, shifted to the right so that the prebranchial chamber of the mantle cavity is large; it can be reduced by muscles in the mantle skirt and the gill displaced from the feeding position. The gill filaments are filiform and elongated and their tips overarch a food groove, except anteriorly. Secretion for trapping food is produced by an endostyle and hypobranchial glands. The food cord, formed by the combined action of cilia on the tips of the filaments and dorsal body wall, is directed to the lateral margin of the right eye stalk. It passes beneath the stalk towards the mouth which is at the end of a very small tubular snout hidden between the bases of the siphons. When food in suspension is scarce, organic matter is collected from the substratum, its supply to the vicinity of the mouth being regulated by the activity of the right tentacle and the foot. Odontophore, salivary and oesophageal glands are reduced. There is no crystalline style; the stomach has large sorting areas and a small gastric shield. A valve prevents entry of paniculate matter to the single duct of the digestive gland. Modifications of shell and foot facilitate burrowing in the uncompacted sand and enable the snail to resist displacement when conditions are adverse. The animal moves easily through soft substrata, but with difficulty over a hard one.
Dorid nudibranchs from eastern Australia (Gastropoda, Opisthobranchia)
Authors: THOMPSON T. E.
Published: August 2009

Collections of nudibranch gastropods made in 1968 are described. All the 18 eastern Australian species of doridaceans (excluding chromodoridiform species) obtained are illustra‐ed and investigated anatomically, often for the first time since their original discovery over a century ago. A list of the dorid nudibranches reliably recorded from Australian waters (compiled by R. Burn) supplements the paper.
The morphology of unique structures on the spines of a deep‐water Hawaiian hermit crab (Crustacea: Decapoda: Paguridae)
Authors: MCLAUGHLIN PATSY A. , LANE CHARLES E.
Published: August 2009

Unique structures, which have been observed on the spines of the chelipeds in a recently described deep‐water Hawaiian hermit crab, Nematopagurus spinulosensoris McLaughlin & Brock, 1974, are herein described. At present the function of these structures is unknown; however, their morphology appears to be more complicated than that of any sensory structures heretofore ascribed to decapod crustaceans.
The status of the Plicatulidae and the Dimyidae in relation to the superfamily Pectinacea (Mollusca: Bivalvia)
Authors: YONGE C. M.
Published: August 2009

In the families Pectinidae and Propeamussidae (scallops) the massive rounded inner ligament layer which provides the opening thrust is bounded by long stretches of anterior and posterior outer ligament layer which, in the absence of teeth, maintain alignment of the valves. In the Spondylidae these outer layers migrate centrally to unite on either side of the inner layer, the primary ligament becoming transversely instead of longitudinally disposed. A secondary ligament of fused periostracum with no tensile strength unites the still long hinge line but secondary ball and socket teeth assume responsibility for alignment of the valves. In the Plicatulidae and the Dimyidae there is the same transverse disposition of the primary ligament but the mantle margins overarch this with production of a continuous longitudinal “external” secondary ligament above the “internal” primary ligament. Although resemblances with the Spondylidae are greater than with the Pectinidae and Propeamussidae, differences from all three are great enough to justify separation of the other two families into a new superfamily Plicatulacea. The monomyarian condition in the Plicatulidae could well have arisen from conditions similar to those in the Dimyidae, that is following cementation when dimyarian and not following byssal attachment as it does in the three families of the now proposed restricted Pectinacea.
Age‐structure and longevity of Common lizard (Lacerta vivipara) populations
Authors: AVERY R. A.
Published: August 2009

Survivorship of L. vivipara in the field was estimated from visual census of the age‐composition of two populations. There was approximately 90% mortality in the first year of life; but the mean expectation of life of an individual which survived to its first birthday was then between four and five years.
The thyroid and parathyroid glands in the Giant panda, Ailuropoda melanoleuca
Authors: CAVE A. J. E.
Published: August 2009

Observations are submitted upon the anatomy of the thyroid and parathyroid glands of Ailuropoda melanoleuca following gland investigation in three specimens. Variations of thyroid configuration and of parathyroid topography are noted, the thyroid vasculature is described in detail and an initial contribution is made to thyroid and parathyroid histology in this genus.
The biology of the anadromous Sea lamprey (Petromyzon mannus) in New Brunswick
Authors: Beamish F. W. H. , Potter I. C.
Published: August 2009

Samples of larvae, metamorphosing and adult representatives of anadromous Petromyzon marinus were collected from rivers in New Brunswick to provide data on aspects of its life cycle. The proportional length of the prebranchial, branchial, trunk and tail regions changed throughout larval life, with the third of these lengths being greater than in Lampetra species, a feature probably related both to the higher number of trunk myomeres and to the greater number of oocytes found in the Sea lamprey. Length‐frequency curves for ammocoetes indicate that in general the duration of larval life is from six to eight years. Metamorphosis is initiated in mid‐July and has probably been completed by November, paralleling the situation in the landlocked Sea lamprey. Small adults of variable size (167–351 mm) attack Alewives (Pomolobus pseudoharengus) and Atlantic salmon (Salmo salar) in the St. John River at points up to 120 km from the estuary. The data indicate that some individuals start feeding in the winter while others do not commence parasitism until the late spring and that this species does not always migrate downstream to saline conditions immediately after metamorphosis. In a sample of 285 nearly mature upstream migrants caught at the Mactaquac Dam on the St. John River, the ratio of females: males was 1: 1.18. No significant difference was found between the mean length, weight and number of trunk myomeres of the two sexes with respective values of 72.9 cm, 892.1 g and 70.1 being recorded for the females and 72.2 cm, 872.6 g and 69.6 for males. The gonadosomic ratio in males was 1.6 and 14.7 in females. The mean number of eggs per female was 210,228 with a range of 151,836 to 304,832. Spawning takes place in late June/early July when the animals show a sexual dimorphism in body proportions and undergo a reduction in total length. The post‐larval phase of the life cycle is considered to last for three or four years, one or two years longer than that recorded for the landlocked form.
House mice bred for many generations in two environments
Authors: Barnett S. A. , Munro K. M. H. , Smart J. L. , Stoddart R. C.
Published: August 2009

Wild house mice, Mus musculus, were bred in (a) warm (control) and (b) cold laboratory environments. More pairs were barren in the cold than in the warm. Fecund pairs in the cold reared fewer young than controls, but their litters were larger at birth and their young were heavier. Nestling mortality declined over ten generations in the cold. Adult mice in the cold were heavier than controls, but not longer. Mice of the tenth generation in the cold, transferred to the warm environment and bred for three generations, were heavier, fatter and more fertile than the controls, but had lighter heart, stomach and kidneys. The secular changes observed were probably genetically determined, but may have included a maternal component.

Wild house mice, Mus musculus L., were trapped, and their descendants reared, in permanently mated pairs, for a number of generations in two laboratory environments, at about 21°C (controls) and ‐3°C, respectively. All mice had sawdust and cottonwool for bedding; but the nests of those at ‐3°C were colder than those in the warm, and fluctuated greatly in temperature.

Reproductive performance was inferior in the cold environment: more pairs were barren, and the fecund pairs reared fewer young than the controls. Yet litters at birth were usually larger in the cold, and the young at three weeks were always heavier. Over ten generations nestling mortality declined at ‐3°C.

From generation 1 on, adult mice at ‐3°C were heavier than the controls, but there was no corresponding increase in body length. Tails were much shorter relative to body length in the first generations in the cold, but returned to control proportions by generation 10. Most of the structural changes in the cold accord with the “rules” of Bergmann and Allen.

The incidence of abnormal sixth lumbar vertebrae was low in all generations at both temperatures.

After nine generations, some mice were transferred from the cold to the warm environment, and bred for a further three generations. There they outstripped the controls both in reproductive performance and in growth. They also had more fat, and a heavier and longer small intestine; but the heart, stomach and kidneys were lighter than those of the controls. Adrenal weights at 21°C declined over the generations, but those of the mice at ‐3°C did not.

The secular changes observed, especially those in the cold environment, are attributed principally to differential selection of genotypes, not to inbreeding; but maternal effects may also have been involved.
Behaviour of Grey seals (Halichoerus grypus) during a breeding season at North Rona
Authors: Anderson Sheila S. , Burton R. W. , Summers C. F.
Published: August 2009

Patterns of colonisation and breeding behaviour were observed in part of the Grey seal rookery at North Rona during the entire breeding season in 1972.

Bulls came ashore when pupping started and joined cows grouped around pools. Numbers of cows and bulls increased to maxima in three and five weeks respectively. Limited access to the rookery and the presence of pools and waterlogged ground influenced site selection by cows.

In the study area the breeding season lasted for 74 days, with individual bulls staying for periods varying from 6–57 days. Daily ratios of bulls to cows varied, but the average ratio was 1:7‐5. It was estimated that 275 cows participated in mating, compared with 37 bulls, during the entire breeding season. The interval of 18 days between peak numbers of cows and bulls ashore corresponded closely with the average time that cows spent ashore.

The aggressive responses of cows in mating behaviour were noted during observations of 114 copulations. It was concluded that a bull requires a very strong sexual drive in order to overcome a cow's aggressive responses, and this reinforces the selective advantage of aggressive dominance in bulls. The stimulus inducing a bull to attempt mating seemed to be the presence of oestrous cows in the rookery rather than an individual cow being in oestrus, because the number of attempted copulations increased even when the number of cows in oestrus temporarily declined during the season. Direct observations and calculations using an index of copulation suggested that the copulation frequency for individual cows ranged from 2.5‐3.6. A bull's participation in mating, and therefore, its genetic influence, was related to the length of its stay in the rookery, and from this evidence it was deduced that a social hierarchy existed amongst the bulls.

Appraisal of the results led to the conclusion that the Grey seal bull maintains a high level of sexual activity so as to mate with as many cows as possible, rather than ensuring exclusive access to cows through territorial fighting and boundary display.
Perinatal activities in the Grey seal (Halichoerus grypus)
Authors: Burton R. W. , Anderson Sheila S. , Summers C. F.
Published: August 2009

Births and postnatal behaviour were observed at a breeding assembly of Grey seals on North Rona. Birth is extremely rapid and the cow immediately turns to smell the pup. Smelling continues at intervals, particularly during the first 10 min after birth and allows the cow to establish the identity of her pup. She also smells the placenta and defends it against attack by gulls. Disturbance by gulls, neighbouring seals and human intrusion may lead to the cow failing to establish a bond with the pup and consequently abandoning it.