bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of rainfall on range in a female desert ungulate: the Arabian oryx (Oryx leucoryx) in the Sultanate of Oman
Authors: Corp N. , Spalton A. , Gorman M. L. 
Published: February 2006

AbstractIn this study we investigated the effect of rainfall on the home range (calculated over 90 days) of adult female Arabian oryx (Oryx leucoryx) in a reintroduced population in central Oman. We looked at response to rainfall for six rain events in the period June 1986 to January 1992; rainfall was localized on five occasions and on one occasion covered the study area. Response, in terms of range and core area, showed considerable variation between rainfall events, perhaps as a result of variation in ranging behaviour between individual oryx. However, in the first 90 days after localized rainfall the home range and core area of oryx outside rain areas increased before decreasing significantly 91–180 days after rain. In comparison, range and core area of oryx inside areas of localized rainfall either did not change or decreased after rainfall as animals took advantage of improved conditions locally rather than investigating grazing elsewhere. When rain fell over the whole study area, range size did not change, but there was an immediate increase in core area and a reduction in range overlap indicating movement to new areas. During extended drought very localized rainfall caused oryx to move quickly to areas of new rain and by 28 days 70% of all adult females had found fresh grazing. Thereafter numbers declined to around 30% by 225 days, before oryx again moved back into the new rain areas. We attributed this pattern of movement to changes in the nutritional quality, measured as crude protein, of available forage. Data for single animals revealed considerable individual variation in response to rainfall; some animals moved quickly to rain whilst others failed to reach it. This variation had consequences for reproductive success and survival and illustrated that, for the oryx, response to rainfall is a key to desert success.
Presence of acid phosphatase in the epidermis of the regenerating tail of the lizard (Podarcis muralis) and its possible role in the process of shedding and keratinization
Authors: Alibardi L. 
Published: February 2006

AbstractThe activity and distribution of the lysosomal marker enzyme acid phosphatase have been studied in the epidermis during tail regeneration in the lizard Podarcis muralis. This study gives information both on the mechanism of separation of the old from the new epidermal generation and on the involvement of lysosomes in β‐ and α‐keratinization in lepidosaurians. The biochemical analysis shows that the activity of acid phosphatase was higher in the regenerating tail than in the normal tail until the stage of skin shedding at around 25–30 days post‐amputation. The enzyme was present in keratinizing layers of epidermis, and particularly in the shedding layer. The shedding layer followed the outline of the regenerating scales beneath the wound in the epidermis showing that lysosomal enzymes are involved in epidermal shedding. The ultrastructural study showed that acid phosphatase was initially localized within the lysosomes but, with the progress of differentiation, it also appeared free within the cytoplasm of the cornifying cells of the shedding complex and of the β‐keratinizing cells, and in the intercellular space among them. The role of lysosomal enzymes in the shedding process and their involvement in the mechanism of β‐keratinization is discussed. While the process of β‐keratinization has an intracellular and extracellular localization of acid phosphatase, the process of α‐keratinization shows that most acid phosphatase is localized within the cell. Lysosomes and mesos granules containing acid phosphatase were concentrated in the cytoplasm of differentiating mesos cells. Some mesos granules later discharged their contents into the extracellular space. The α‐layer was partially formed in proximal regenerated scales around 30 days post‐amputation. Lysosomes appeared to concentrate within pre‐keratinizing cells of the α‐keratin layer and little reactivity was seen extracellularly.
Phylogenetic relationships of otters (Carnivora: Mustelidae) based on mitochondrial cytochrome b sequences
Authors: Koepfli K.‐P. , Wayne R. K. 
Published: February 2006

AbstractOtters are classified in the Lutrinae and are united by a suite of semi‐aquatic adaptations that distinguish them from the rest of the Mustelidae. Past systematic studies have been based primarily on overall similarity of morphological characters but have not been concordant, with regard either to relationships within the subfamily or to the relationships of the Lutrinae to other taxa in the Mustelidae. We evaluate the relationships among nine of the 13 species of otters and their position in the Mustelidae through phylogenetic analysis of the complete nucleotide sequence of the mitochondrial cytochrome b gene. Based on the sequence data presented here, our results suggest that otters are divided into three primary clades that include: (1) the North American river, neotropical and marine otters; (2) the sea, Eurasian, spotted‐necked, cape clawless and small‐clawed otters; and (3) the giant otter. Furthermore, our results indicate that among sampled mustelid taxa, members of the genus Mustela are most closely related to otters. The hierarchical relationships among clades are not well resolved, particularly the monophyly of otters, largely because a pattern of short internal branches combined with long terminal branches suggests a rapid evolutionary radiation. Estimates of divergence time calibrated by the fossil record suggest that the lineages leading to the North American river, neotropical and marine otters, and the giant otter diverged before the end of the Miocene, much earlier than predicted from the fossil record.
DNA fingerprinting reveals high levels of genetic diversity within British populations of the introduced non‐native grey squirrel (Sciurus carolinensis)
Authors: David‐Gray Z. K. , Gurnell J. , Hunt D. M. 
Published: February 2006

AbstractIn general, if populations are founded by very small numbers of individuals, low levels of genetic diversity amongst subsequent generations known as founder effects, can be predicted to occur as a result of genetic drift (Franklin, 1980; Lacy, 1997). A loss of genetic variation has been reported in several species that have experienced genetic bottlenecks because of habitat fragmentation, geographic isolation or inbreeding depression (Gilbert et al., 1990; Hoelzel & Dover, 1991; Ellegren et al., 1993; Timms et al., 1993; Wauters, Casale & Dhondt, 1994; Wauters, 1997). This loss of genetic diversity can have deleterious effects on reproductive output. For example, laboratory and captive breeding programmes provide extensive evidence of both decreased fecundity and reduced juvenile survival (Ralls & Ballon, 1982, 1986; Du Bois, Dhondt & Van Puijenbroek, 1990; Brock & White, 1992), and research conducted on natural populations of common shrews Sorex araneus has reported similar findings (Stockley et al., 1994). However, genetic evidence from some wild populations shows that highly inbred populations can survive and thrive despite low levels of genetic variability (Gilbert et al., 1990; Wayne et al., 1991; Ellegren et al., 1993). Grey squirrels Sciurus carolinensis, were introduced into Britain from eastern North America on several occasions between 1876 and 1910. Furthermore, between 1906 and 1937 grey squirrels were translocated to a variety of different locations within Britain (Middleton, 1931; Shorten, 1954). From the 1930s it rapidly expanded its range and is now ubiquitous to almost all of central and southern England, Wales and some lowland areas of Scotland (Lloyd, 1962, 1983; Gurnell &; Pepper, 1993). In view of this highly successful colonization by an invading species the grey squirrel appears to have been unaffected by any loss of genetic diversity as a result of recent population bottlenecks. We have used DNA fingerprinting (Jeffreys, Wilson & Thein, 1985a), a technique which provides a good indication of genome variability (Jeffreys et al., 1985b; Kuhnlein et al., 1990; Kunieda et al., 1993) to assess overall levels of genetic diversity in two British grey squirrel populations; Alice Holt Forest on the borders of Hampshire and Surrey in southern England and Thetford Forest in East Anglia.
Use of artificial water supplies by captive‐born mountain gazelles (Gazella gazella) released in central Arabia
Authors: Dunham K. M. 
Published: February 2006

AbstractTagged, captive‐bred mountain gazelles were released into Hawtah Reserve, Saudi Arabia. More than 1 year after they were freed, their drinking behaviour at two water troughs was recorded for 2.5 months during late summer/autumn, using automatic cameras and monitors triggered when an infra‐red beam was broken. Only 30% of gazelles (n= 40) were recorded drinking and only individuals which lived close to troughs drank. No gazelles visited the one natural water point. Among gazelles which lived close to the troughs, older individuals were more likely to drink than younger animals. The noise of the cameras as they took a photograph frightened some gazelles and may have influenced their frequency of drinking after they were photographed for the first time.
Estimating the population density of Galemys pyrenaicus in four Spanish rivers
Authors: Nores C. , Ojeda F. , Ruano A. , Villate I. , González J. , Cano J. M. , García E. 
Published: February 2006

AbstractIn spite of the studies carried out for several decades on Galemys pyrenaicus, no paper has specifically estimated desman densities, although indirect information can be inferred from the studies in the French Pyrenees on the use of space by Stone & Gorman (1985) and Stone (1987a).
Wing shape in New Zealand lesser short‐tailed bats (Mystacina tuberculata)
Authors: Webb P. I. , Sedgeley J. A. , O'Donnell C. F. J. 
Published: February 2006

AbstractThe theoretically optimal shape of a bat's wing changes with flight mode (Norberg, 1987; Norberg & Rayner, 1987) and several studies have shown this theory to be largely born out in practise (Aldridge & Rautenbach, 1987; Norberg & Rayner, 1987; Crome & Richards, 1988). For instance, bats with wings of relatively low surface area (high wing loading) that are also relatively long and thin (high aspect ratio) tend to be fast, straight fliers spending most of their flying time foraging or commuting in open areas such as pasture or above the forest canopy (Norberg & Rayner, 1987). In such bats manoeuvrability is improved by the possession of small, pointed wing tips to reduce drag. In contrast bats with wings of relatively high surface area that are also relatively short and wide with large, rounded wing tips tend to be slow, highly manoeuvrable fliers foraging in cluttered habitats such as woodland (Norberg & Rayner, 1987).
The influence of public access and sett visibility on badger (Meles meles) sett disturbance and persistence
Authors: Jenkinson S. , Wheater C. P. 
Published: February 2006

AbstractThe impact of public rights of way on badger setts was examined in the Bradford area of West Yorkshire using comparisons of 38 setts surveyed in 1985–1996 and again in 1992–1993. Badger setts were compared on the basis of whether they were still in use or not, and on the number of illegal disturbance events recorded over the study period. The number of, and distance from, public accesses did not influence sett persistence, and the least frequently disturbed setts (i.e. those with an average of one or less disturbance incidents every 2 years) were closer to a larger number of accesses. Frequency of poaching was high near to heavily disturbed setts and those no longer occupied at the later survey. Less frequently disturbed setts were associated with landowners who were unsupportive of badger conservation: it is possible that such landowners are highly protective of their land and thus incidentally reduce the frequency of poaching and other forms of disturbance. Setts in areas with formal authorized shooting were less disturbed. Setts still in use tended to be in open habitats and visible from roads and nearby dwellings. Setts in open areas were less often disturbed than those in wooded sites. Since public access may not reduce sett persistence and may even be beneficial in an area of high wilful persecution, there are implications for the management of public access.
Morphological diversity of ground beetles (Coleoptera: Carabidae) in Scottish agricultural land
Authors: Ribera I. , McCracken D. I. , Foster G. N. , Downie I. S. , Abernethy V. J. 
Published: February 2006

AbstractThe morphospace defined by 87 species of ground beetle (Coleoptera: Carabidae) of Scottish non‐forested habitats is described with multivariate methods, using 13 linear quantitative measurements of the body, hind legs, eyes and antennae, plus five qualitative characters concerned with body shape, colour, wing development, and pubescence. Relationships between pairs of variables are studied with phylogenetic independent contrasts, using two different taxonomic classifications as an approximation to the phylogeny of the group. The first ordination axis of the morphospace was found mainly to reflect the positive correlation between length of the antennae and length of the hind legs, the second to reflect the width of the head, diameter of the eye and pronotum height, and the third the width of the pronotum and elytra, length of the metatrochanter and width of the metafemur. The principal relationships involving qualitative characters were between colour of the body and legs and shape of the pronotum with ordination axes, wing development with width of the elytra, and pubescence with colour of the legs. Most correlations between quantitative variables, in particular those most influencing the ordination axes of the morphospace, remained significant when measured with phylogenetic independent contrasts using both classifications. Independent contrasts comparing qualitative with quantitative variables or ordination axes were only significant for the colour of the body with the second axis for both classifications used, and length of the antennae with colour of the body and shape of the pronotum for only one of the classifications. The main morphological trends within the morphospace defined are related with published information on their performance, in particular running speed and pushing abilities, following previous work on the functional morphology of the group. The morphospace defined by the species studied is a fundamental tool that will allow further investigations on the relationships between their morphology and life traits, as well as on the relationships of the functional diversity thus characterized with environmental correlates.
Foraging strategies and food partitioning in the neotropical frugivorous mammals Caluromys philander and Potos flavus
Authors: Julien‐Laferrière D. 
Published: February 2006

AbstractThe bare‐tailed woolly opossum, Caluromys philander, and the kinkajou, Potos flavus, are two syntopic neotropical nocturnal, arboreal and frugivorous mammals. Because of close ecology but great difference in size (weight 300 vs 3000 g), they represent pertinent models to examine the influence of size on foraging strategy. These species were studied by radio‐tracking and direct observation during 22 months in a tropical forest in French Guiana. Both mammals’ foraging strategies with regard to flowers and fruits are characterized as follows: (1) numerous plant families and species are exploited; (2) most plant species are selected according to their abundance; (3) diet selectivity and diversity are similar in both mammals; (4) relative parts of flowers and fruits in the diet vary according to their year‐long availability; (5) the choice of fruiting species is not related to the morphological type, size, or nutritious quality of fruits but instead depends on easy access to the edible part; (6) the length of foraging bouts is correlated with production for the most frequently exploited tree species; (7) feeding bouts are shorter in P. flavus than in C. philander; (8) P. flavus exploits large, highly productive canopy trees, while C. philander also visits canopy trees with low production and understorey trees. In conclusion, both mammals are opportunistic flower‐ and fruit‐eaters, but the larger species (P. flavus) exploits larger, more scattered food patches, while the smaller one (C. philander) also exploits smaller, more numerous and more evenly distributed food patches.
Study of the spatial organization of the gas exchange components of a snake lung – the sandboa Eryx colubrinus (Reptilia: Ophidia: Colubridae) – by latex casting
Authors: Maina J. N. , Veltcamp C. J. , Henry J. 
Published: February 2006

AbstractThe vasculature and the air ways of the lung of the sandboa Eryx colubrinus were cast using latex rubber, corroded, and studied with a scanning electron microscope to determine the shape, topographic configurations, and relative sizes of the gas exchange components. The sandboa had a right lung and a vestigeal left one. The lung, which terminated close to the anus, consisted of two distinctive anatomical regions. The exchange tissue was located in the cranial half of the lung while the caudal one consisted of a transparent avascular ‘air sac’. The right pulmonary artery, which was found on the laterodorsal aspect of the lung, gave rise to branches which supplied blood to the pleura and the faveolar septal walls. The geometric relationship between the flow of the venous blood (from the pulmonary artery) into the parenchymal zone of the lung and the convective/diffusive outwards air flow from the central air duct into the parenchyma is essentially counter‐current: the air moves centrifugally and the blood centripetally. However, the arrangement between the air flow in central air duct and that of the venous blood is cross‐current (i.e. the two media run in directions perpendicular to each other). These architectural schemes are similar to those that have developed in the avian lung. In fact, in its simplest form, the parenchymal region of the snake's lung corresponds with a single tertiary bronchus (parabronchus) of a bird lung. Further investigations are necessary to identify the factors that enforced this morphological convergence and to verify whether these congruent features are analogous, as they would seem to be, or from a phylogenetic perspective possibly homologous.
Geophagy in the golden‐faced saki monkey (Pithecia pithecia chrysocephala) in the Central Amazon
Authors: Setz E. Z. F. , Enzweiler J. , Solferini V. N. , Amêndola M. P. , Berton R. S. 
Published: February 2006

AbstractThe golden‐faced saki monkeyPithecia pithecia chrysocephala(Cebidae, Primates) was observed eating soil from termite nests during a long‐term study of a family group in a Central Amazonian forest fragment. In this paper we describe the behaviour involved in the geophagy in these monkeys, and the results of geochemical and physical analyses of the termite nest material, as well as root mat and topsoil samples below the trees, in order to clarify the possible reasons for it. The sakis ate soil from nine arboreal termite nests on 26 soil feeding‐bouts (in 853 observation hours); 25 soil feeding‐bouts occurred in March 1987 (rainy season), during 19 days or 132 observation hours, and occupied 0.7% of the feeding time. Geophagy frequencies did not differ between sexes (17 feeding‐bouts of four females and 8 for two males). Mineral composition was higher in arboreal termitaria than in the topsoil. Kaolinite was the major clay component. Tannin adsorptive capacity, tested through a modified radial diffusion method of Hagerman, was around 10–20%, similar to a control with kaolin (10–20%), but lower than bentonite or celite (30–45%). The observations reported here, although inconclusive as to the function of geophagy in this species, indicate that it is not a mineral supplement during times of scarcity or high consumption of leaves, as has been reported for other primates, nor that it is related to fruit consumption (redressing possible mineral imbalance), as has been suggested for some other frugivorous mammals. Our results do not rule out tannin adsorptive hypothesis for the ingestion of clays, but, being an irregular habit, we argue that it is most likely related to rare and occasional dietary components.
Use of space and social organization of female mountain gazelles (Gazella gazella gazella) in Ramat HaNadiv, Israel
Authors: Geffen H. , Perevolotsky A. , Geffen E. , Yom‐Tov Y. 
Published: February 2006

AbstractThe social organization of female mountain gazelles was studied on Mount Carmel, Israel. The behaviour of distinctly recognized individuals was studied by year‐round observations. Female gazelles lived in groups whose composition remained constant throughout the year, and new females did not freely enter the established groups. Group home ranges overlapped, but various groups replaced each other in the same area at different times of the day. Different groups tended to use different parts of the overlapping home range. In general, but especially in summer, the different groups largely avoided being synchronously together in the same area. The occurrence of two groups in the same area at the same time was a rare event and when it occurred, a high rate of agonistic interaction was observed between the groups. Hence, groups of female mountain gazelles hold and defend temporal territories against other female groups. Mean seasonal group size ranged between 3.4 and 6.4 and was largest during winter, when groups of females joined together occasionally and little agonistic interaction was observed between the groups. It is suggested that group size is affected by food availability and predation pressure.
Do acid rain and calcium supply limit eggshell formation for blue tits (Parus caeruleus) in the U.K.?
Authors: Ramsay S. L. , Houston D. C. 
Published: February 2006

AbstractThe normal diet of most small passerines contains insufficient calcium for effective eggshell formation and birds must often forage specifically for calcium‐rich items in the environment. It has been demonstrated that anthropogenic acid precipitation can significantly reduce levels of available calcium in soil and the abundance of calcareous items such as snail shells. Recent research in areas adversely affected by acid precipitation on Continental Europe has suggested that reduced calcium availability has resulted in an increased incidence of eggshell defects in small birds. In this paper we present data from one of the areas of the U.K. most severely affected by acid precipitation and where snail abundance (0.36 snails per m2) and exchangeable soil calcium levels (0.02 mg g−2) were very low: lower than values at sites in the Netherlands where severe eggshell defects occurred. The provision of supplementary calcium and the examination of eggshells, however, provided no evidence that blue tits Parus caeruleus were constrained in their ability to form effective eggshells as a result of calcium deficiency. We suggest that other factors, besides low calcium availability, may be contributory to the high incidence of eggshell defects seen in other areas.