bluuebunny/crossref_metadata_2025_split huggingface dataset:
Taxonomy of shrew‐tenrecs (Microgale spp.) from eastern and central Madagascar
Authors: Stephenson P. J. 
Published: September 2010

As remaining habitats come under threat from deforestation, there is an urgent need to survey the insectivore fauna of Madagascar. However, within the endemic family Tenrecidae there is uncertainty over the taxonomy of the largest genus, Microgale. The number of species recognized in this genus ranges from 10 to 21.In the present study, Microgale specimens were obtained by live‐trapping in four forests in eastern and central Madagascar. Data on morphology, ecology and behaviour are used to review Microgale taxonomy. It is proposed that M. melanorrhachis, M. longirostris and M. laiva are distinct species, so that a total of 16 species are recognized in the genus. Further trapping is advocated to clarify the situation. The consequences for conservation are discussed
Diving behaviour and energetics in breeding little penguins (Eudyptula minor)
Authors: Bethge P. , Nicol S. , Culik B. M. , Wilson R. P. 
Published: September 2010

We present data on the diving behaviour and the energetics of breeding little penguins in Tasmania, Australia. Using an 18 m long still water canal in conjunction with respirometry, we determined the energy requirements while diving. Using electronic devices measuring dive depth or swimming speed, we investigated the foraging behaviour at sea. Cost of Transport was calculated to be minimal at the speed the birds prefer at sea (1.8 m/s) and averaged 11.1 J/kg/m (power requirements at that speed: 20.0 W/kg). Metabolic rate of little penguins resting in water was found to be 8.5 W/kg. The externally‐attached devices had no significant influence on the energy expenditure.Foraging trips can be divided into four distinct phases with different diving behaviours. A mean of 500 dives was executed per foraging trip lasting about 18 hours with 60% of this time being spent swimming. The total distance travelled averaged 73 km per day, although foraging range was about 12km. Mean swimming speed of little penguins at sea was 1.8 m/s, maximum swimming speed was 3.3 m/s. More than 50% of all dives had maxima not exceeding 2 m. Maximum depth reached was 27 m. Mean dive duration was 21 s. There were inter‐sex differences in diving behaviour as well as changes in foraging behaviour over the breeding period. Aerobic dive limits (ADL) in the wild were estimated between 42 and 50 s. From the swim canal experiments we derived an ADL of 44 s. Total oxygen stores were calculated to be 45 ml O2/kg. Only 2% of all dives exceeded the ADL. FMRs at sea were calculated to be between 1280 and 1500 kJ/kg/d according to chick size. The yearly food requirements of a breeding little penguin amount to 114 kg.
Postcranial adaptations for climbing in Loridae (Primates)
Authors: Runestad Jacqueline A. 
Published: September 2010

The Loridae are an arboreal family of small primates that are specialized for slow and quiet climbing. This paper examines the relationship between lorid locomotory behaviour and postcranial skeletal morphology. Lorid humeral and femoral diaphyseal geometric cross‐sectional properties, articular surface areas, and lengths are compared to those properties in other small primates with less specialized locomotory behaviour. The comparative sample includes both closely related prosimians and more distantly related platyrrhines.Results indicate that lorids have greater humeral and femoral diaphyseal rigidity than other quadrupedal primates of similar body size, suggesting that lorid limbs are subjected to greater forces. Lorids also have relatively larger humeral and femoral articulations, corresponding to field and laboratory observations which indicate that lorid joints are highly mobilc. In addition, lorids have long humeri relative to femoral length, and compared to humeral length in less specialized prosimians of similar body mass. Long humeral length relative to femoral length is interpreted as a climbing adaptation because similar limb proportions are also seen in many non‐primate climbers. Altogether, humeral and femoral diaphyseal cross‐sectional properties, articular surface areas, and lengths comprise a suite of characters which have potential for identifying climbing specialists in the fossil record.
Patterns of multiple paternity within and between annual reproduction cycles of the fire salamander (Salamandra salamandra) under natural conditions
Authors: Steinfartz S. , Stemshorn K. , Kuesters D. , Tautz D. 
Published: September 2010

AbstractWe have investigated patterns of paternity in a population of the fire salamander Salamandra salamandra in Germany under fully natural conditions. Pregnant females were caught after hibernation in their natural habitat and their offspring were genotyped with different sets of microsatellite loci to assess paternity. Each female was marked with a transponder and released at the same place where it had been caught. We were able to recapture several marked females in the following years and to analyse the offspring arrays of six females for different reproductive years between 2000 and 2001 for possible long‐term sperm storage and repeated sperm usage. The reconstruction of paternal genotypes for 21 female offspring arrays with the GERUD 1.0 program showed that multiple paternity is frequent under natural conditions with more than half of the females showing two or three fathers for their offspring cohorts. Despite the fact that S. salamandra is capable of long‐term sperm storage under captive conditions, under natural conditions we did not find evidence for long‐term sperm storage and repeated sperm usage for the six analysed female offspring arrays from consecutive years. This might be an indication for possible cryptic female choice owing to differences of sperm quality between stored and freshly uptaken sperm or degradation of sperm after fertilization. Furthermore, we found that males in nature do not contribute equally to a female's clutch when it is sired from multiple fathers. Currently, it is not clear whether such a paternity pattern reflects a simple ‘topping off’ mechanism of sperm in the spermathecae of the female as described for the newt species Taricha granulosa or whether this is the result of intensive sperm competition.
First observations on South America's largely insectivorous canid: the hoary fox (Pseudalopex vetulus)
Authors: Courtenay O. , Macdonald D.W. , Gillingham S. , Almeida G. , Dias R. 
Published: September 2010

AbstractThe breeding behaviour and social dynamics of a free‐ranging group of hoary foxesPseudalopex vetuluswere studied in the central cerrado (savannah) region of Brazil. The average adult size was 3.42 kg [95% confidence limits (CL): 2.92–3.91 kg]. The breeding pair occupied overlapping home ranges of 420–456 ha, where they reared a single litter of five offspring (M:F: 3:2) in 12 months. There were no additional adult group members and all offspring dispersed whenc. 10 months old, at least three of which (both sexes) established a home range adjacent to the natal territory. The proportion of time invested in rearing offspring by the breeding female declined significantly (33–2%) with increasing offspring age (pre‐weaning to offspring independence), in contrast to that of the breeding male, which was relatively constant (17–29%); the male acted as a chaperone to foraging offspring, mostly in the absence of the breeding female. Hoary fox diet comprised predominantly of insects, particularly termites and dung beetles, none of which was sufficiently bulky to make carriage to the cubs energetically efficient.
Morphological consequences of range fragmentation and population decline on the endangered Iberian lynx (Lynx pardinus)
Authors: Pertoldi C. , García‐Perea R. , Godoy J. A. , Delibes M. , Loeschcke V. 
Published: September 2010

AbstractThe Iberian lynx Lynx pardinus is one of the world's most endangered felids and is vulnerable to human‐induced mortality and habitat loss, which reduce population size and accelerate the loss of genetic variation. Twenty‐five metric traits of Iberian lynx skulls have been measured on 95 skulls collected between 1872 and 2003. The skulls belong to three geographically distinct areas/populations, which have recently diverged from each other as a consequence of increased habitat fragmentation: Doñana area, Sierra Morena mountains and Montes de Toledo area. The morphometric study was undertaken using univariate, multivariate and admixture analysis approaches, and all three techniques provided evidence for morphometric differentiation, both in skull size and shape, among the three populations for both males and females. Environmental and genetic forces that may have shaped these patterns are discussed. The males of the population of the Doñana area showed a different degree of reduction in size in nine of the skull traits with time, which has been suggested to be partly because of worsened habitat conditions. However, the heterogeneity of the degree of mean size reduction and the relatively high degree of reduction of some of the skull traits investigated (>4%), which have altered the original proportions between the skull variables, could also partly be attributed to inbreeding depression in the Doñana population. The phenotypic variability of the skull traits showed significant increases (two traits) or decreases (nine traits) with time, and this different pattern of change with time has been suggested to be because of a different number of genes controlling the traits with different degrees of dominance and epistatic interactions. The increased phenotypic variability of two of the traits has also been attributed to a possible decreased level of developmental stability, which can be produced by environmental and/or genetic stress. The findings of this investigation contribute to the discussion about the utility and the limits of quantitative genetics techniques for conservation purposes.
What is the taxonomic status of the Cambodian banteng and does it have close genetic links with the kouprey?
Authors: Hassanin A. , Ropiquet A. 
Published: September 2010

AbstractIn a recent paper, Galbreath, Mordacq & Weiler (2006) concluded that the kouprey Bos sauveli was not a natural species, but rather a feral animal derived from hybridization between banteng Bos javanicus and zebu Bos taurus indicus. Here, we analyze two mitochondrial genes (cytochrome b and subunit II of the cytochrome c oxidase) for all the seven species of the subtribe Bovina, including new sequences for several specimens of banteng, zebu and gaur of Cambodia. Our analyses indicate that mitochondrial sequences of Cambodian banteng are divergent from those of Javan banteng (mean difference =4.27%), but similar to those of kouprey (1.25%). We propose two conflicting hypotheses to interpret these results: (1) the Cambodian and Indonesian banteng belong to two distinct species, and the kouprey derived from Cambodian banteng; (2) all subspecies of banteng belong to Bo. javanicus, but the mitochondrial genome of kouprey was transferred by natural hybridization into the ancestor of Cambodian banteng. Morphological, ecological and ethological characteristics of banteng and kouprey rather support the second hypothesis. However, we need to sequence nuclear markers, and to analyze banteng from Lao, Myanmar, Thailand and Vietnam, to give a definitive conclusion on the taxonomic status of banteng and kouprey.
MINERAL NUTRITION IN TIME AND SPACE
Authors: RORISON I. H. 
Published: September 2010

SummaryInterest in mineral nutrition during the last 20 years has centred increasingly on its dynamic aspects. This has led to a consideration of temporal variation, both diurnal and seasonal, and of spatial patterns as they affect nutrient supply. The response of plants to such variations are reviewed in the light of distribution and survival. Although all plants require the same small number of mineral elements, there is evidence of fine tuning in relation to soil heterogeneity. This allows a large number of nutritional options which in turn may influence coexistence and change. Selected examples for nitrogen and phosphorus are given and attention drawn to the need for further study, not only of nutrient interactions, of the energy costs of different nutrient pathways and of messenger functions of key nutrients (e.g. N and P linking activities of both root and shoot), but also of activities around the root surface; the micro‐environment produced and the involvement of microflora and fauna.
THE COMPARATIVE ECOLOGY OF FLOWERING
Authors: KAY Q. O. N. 
Published: September 2010

SummaryThe major roles of flowering are in sexual reproduction and in fruit and seed production. Flowering competes with vegetative growth and vegetative reproduction for resources, and involves heavy resource costs which are often much greater than those required for seed production alone. Interactions between plants dependent upon flowering may be competitive or mutualistic. Theoretical models suggest that these interactions may often be of primary importance in determining whether different species or genotypes coexist, or displace or mutually exclude one another, and may thus be responsible for the heavy investment in flowering, but very few cases have been analyzed satisfactorily. The existence of simultaneously or sequentially flowering guilds of species with similar floral characteristics may be a consequence of mutualistic interactions. Flowering strategies and the range of possible interactions dependent upon flowering are potentially very diverse but are constrained by the physical and biotic environment, sometimes very severely.
BOTANICAL CONTRIBUTIONS TO CONTEMPORARY ECOLOGICAL THEORY
Authors: GRIME J. P. , HODGSON J. G. 
Published: September 2010

SummaryIn the search for general principles in ecology, the role of botany has often been subordinate to those of mathematics, genetics and zoology. This paper identifies three important areas of ecological research (competition, coexistence, and relationships between anti‐herbivore defence and decomposition processes) where comparative studies of autotrophic plants can play a leading part in analyses of the structure of communities and the functioning of ecosystems. With respect to a fourth research topic (ecological constraints arising from evolutionary histories), a stronger botanical response to the zoological lead is advocated.
Nitrate inhibition of N2 fixation in Phaseolus vulgar is L. cv. OAC Rico and a supernodulating mutant
Authors: Hansen Alexander P. , Martin Peter , Buttery Brian R. , Park Soon J. 
Published: September 2010

summaryTime‐integrated, 15N–based determinations of N2 fixation were undertaken on common bean (Phaseolus vulgaris L.) cv. Rico and its supernodulating mutant RBS15. Plants were cultured in pots filled with quartz sand and experienced three different (0.5, 3.0, 6.0 mol m3) constantly maintained levels of nitrate for a total period of 65 d. Irrespective of nitrate treatment, biomass production of RBS15 was consistently lower compared to Rico. Nodule numbers of the wild type were only slightly elevated in response to a rise in nitrate concentration from 05 to 30 mol m3, while nodule numbers of RBS15 increased substantially, indicating that nodulation of the mutant was N limited in the 0.5 mol m 3 treatment. A further rise in nitrate concentration failed to induce any more change in the mutant, but caused earlier senescence in Rico nodules. Both genotypes decreased their dependency on atmospheric N2 in the presence of increasing quantities of nitrate in the rooting medium, with relatively small differences between genotypes. Calculated in absolute terms, total N2 fixation was mostly lower in the mutant despite its higher nodule numbers. Much larger differences appeared when the amount of N., fixed per unit nitrogen invested into nodules was compared. Here the mutant exhibited significantly lower values. The data suggest that nodulation of the supernodulating mutant is tolerant to nitrate, while N, fixation in both genotypes is detrimentally affected.
Chronology and mechanisms of P uptake by mycorrhizal sweet potato plants
Authors: Oapos;KEEFE D. M. , SYLVIA D. M. 
Published: September 2010

summaryVesicular‐arbuscular (VA) mycorrhizal and non‐mycorrhizal sweet potato plants [Ipomoea batatas (L.S) Lam. cv. White Star] were grown in a glasshouse in a phosphorus (P)‐fixing soil in order to (i) establish the chronology of mycorrhiza‐mediated P uptake, (ii) document the distribution of total and metabolically active external hyphae in relation to roots, root hairs and P‐depletion zones at the time when the P‐uptake response first becomes apparent, (iii) evaluate the pore‐size distribution of the soil relative to the radii of roots, root hairs and hyphae of mycorrhizal fungi, and (iv) determine if sweet potato mycorrhiza alter the organic acid composition of the rhizosphere. Phosphorus inflow, VA mycorrhizal root colonization, and active hyphae increased during the first half of an 8 wk experiment. During the latter half of the experiment, however, colonization and active hyphae increased while P inflow decreased. Roots colonized by mycorrhizal fungi supported a higher proportion of active hyphae in the soil than non‐colonized roots. In a second experiment, hyphal distribution around individual roots colonized by mycorrhizal fungi was not consistently different from hyphal distribution around non‐colonized roots. Hyphae of mycorrhizal fungi were of a diameter that would allow them to penetrate pores that hold water at water contents less than field capacity while roots, and to a large extent root hairs, would be excluded from these pores. We found no evidence that sweet potato roots, whether or not they were colonized by mycorrhizal fungi, altered the organic acid composition of the rhizosphere. We conclude that mycorrhiza mediated P uptake commenced with the onset of colonization by the fungi and was due to a change in the ability of the root to come into contact with the soil solution.
Mycorrhizas and drought resistance of Picea sitchensis (Bong.) Carr
Authors: LEHTO TARJA 
Published: September 2010

summaryMycorrhizal [Paxillus involutus (Batsch) Fr.] and non–mycorrhizal Sitka spruce [Picea sitchensis (Bong.) Carr.] seedlings were grown to comparable size and with comparable shoot N, P and K concentrations in a perlite nutrient solution culture. Shoot water potentials of mycorrhizal and non–mycorrhizal seedlings were related to the moisture content of the substrate during a drying cycle. At any given substrate moisture content, mycorrhizal plants had significantly lower water potentials than non–mycorrhizal plants, the difference being about O.l MPa. In a factorial experiment there was no effect of mycorrhizal infection on stomatal conductance or net photosynthetic rate in either well–watered or droughted seedlings.
Effects of ambient air pollution in open‐top chambers on bean (Phaseolus vulgaris L.)
Authors: SCHENONE G. , BOTTESCHI G. , FUMAGALLI I. , MONTINARO F. 
Published: September 2010

summaryField‐grown bean crops (Phaseolus vulgaris L.) were exposed to either ambient non‐filtered or filtered air in open‐top chambers at two sites in the Po plain (Northern Italy) in 1988 and 1989. Three cultivars were utilized in 1988 (Taylor's Horticultural, Lingua di Fuoco, Saluggia), one in 1989 (Taylor's Horticultural). The crops grown in ambient non‐filtered air showed significant reductions in yield compared with those in filtered air at both sites for the two years. Yield decrement of the most sensitive cultivar (Taylor's Horticultural) reached 31 % at the urban site in 1988 and 31% at the rural site in 1989. Severe foliar injury attributable to oxidants was observed on plants kept in non‐filtered air or grown in non‐chambered control plots. The instrumental monitoring of air pollutants showed 7 h means of O3 up to 50 nl I−1 during the experiments; it is known that these values can cause yield losses to sensitive crops. The concentrations of other pollutants (SO2 and NO2) were on the contrary below the known thresholds for yield losses to plants. We can argue that ambient ozone is the major air contaminant responsible for the observed yield losses of bean; the negative effects can occur both at rural and urban sites because of the widespread presence of photooxidants in the Po plain.
An in vitro assay for incompatibility between Triticum aestivum L. and Secale cereale L.
Authors: OSTASH M. , FAUTRIER A. G. , FIELD R. J. 
Published: September 2010

summaryA liquid medium was developed for in vitro germination and growth of rye (Secale cereale L.) pollen. Addition of style extracts from ‘Otane’ wheat which were incompatible with rye selectively inhibited pollen tube growth, compared with compatible ‘Chinese Spring’ wheat. Dialysed extracts were most suitable for incompatibility assays. Rye pollen was also selectively inhibited by extracts from self–compatible styles. Intergeneric incompatibility in wheat appears to be controlled by inhibitory style proteins.
The alder [Alnus glutinosa (L.) Gaertn.] problem in the British Isles: a third approach to its palaeohistory
Authors: TALLANTIRE P. A. 
Published: September 2010

summaryThe previous approaches (rational and empirical limits for the alder pollen curve) are discussed in relation to the immigration/establishment and spread/expansion phases. For the former, consistent ‘tail’ values for alder pollen of over 3 % (total land pollen) are considered requisite, lower values being ascribed to long–distance transport. For the latter, a mapped plot of the radiocarbon dates for the initial marked rise in the alder pollen curve, to over 10 %, is presented, using only those diagrams from sites considered stratigraphically reliable and for which the dated samples derive from specific points on the curve (start, mid–rise or finish). Certain ecological considerations, which appear to have been either overlooked or neglected, are dealt with in relation to the thermoclimatic and hygroclimatic demands of alder. Alder establishment seems highly probable by 8000 BP for at least two sites in southeastern England. This supports the view that alder immigrated from Western Germany or Holland. The spread of alder shows a clear regionalism, with a major increase after about 7500 BP, mainly after 7000 BP. The failure of alder to spread north and west from its initial footholds is ascribed to the seasonal, prolonged periods of drought during the Boreal chronozone (c. 7800—‐75 00 BP), i.e. the hygroclimatic conditions were unfavourable. The initial establishment was restricted to the south east of England on account of the thermoclimatic demand and the source areas for seed.The delays shown in its eventual spread north and west are ascribed to unfulfilled thermoclimatic demands, possibly due to low air and sea temperatures. A plea is made for the use of primary sources only, not computer‐stored data, when plotting these phenomena, and for future investigations to create a denser network of reliably dated sites, with unequivocal stratigraphic conditions, continuous pollen diagrams, and with macrofossil investigations when appropriate (excluding wood), at all altitudes.