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961.
A. LOYAU B. MOUREAU M. RICHARD P. CHRISTE P. HEEB G. SORCI 《Molecular ecology resources》2005,5(1):135-139
We tested the cross‐amplification of 37 microsatellites in a population of starlings (Sturnus vulgaris). Twenty‐three of them amplified and five exhibited a large number of alleles per locus and high heterozygosity (on average: 14.6 alleles/locus and HE = 0.704). We assessed the occurrence of extra‐pair paternity (EPP) and intraspecific brood parasitism (IBP) in this population. The EPP rate was 16% to 18% offspring from 43% to 45% of nests. IBP was very variable between two successive years (14% to 27% chicks from 25% to 64% of clutches). These five polymorphic markers will be of potential use in studies of genetic diversity, population structure and reproductive strategy of this species. 相似文献
962.
JULIE L. SMITH NUSHA KEYGHOBADI MICHAEL A. MATRONE RICHARD L. ESCHER DINA M. FONSECA 《Molecular ecology resources》2005,5(3):697-700
In the past, we have developed microsatellite loci from the two most common members of the Culex pipiens complex, Culex quinquefasciatus and Culex pipiens. Here we describe seven additional loci and present an extensive survey of a panel of 20 loci across most of the species and subspecies in the complex as well as in morphologically related species. Because we observed a high degree of polymorphism in the flanking regions, we designed new primers and surveyed multiple populations. We present alternate primers and discuss the cross‐species usefulness of these Culex microsatellite loci in a phylogenetic context. 相似文献
963.
DAN E. CHAMBERLAIN JULIET A. VICKERY DAVID E. GLUE ROBERT A. ROBINSON GREG J. CONWAY RICHARD J. W. WOODBURN & ANDREW R. CANNON 《Ibis》2005,147(3):563-575
Provision of bird food in gardens is a common activity that may provide an alternative food source to birds in winter. Long-term survey data recording the weekly presence of all bird species using garden feeders in the winter were analysed to see if there was any evidence of trends in feeder use between 1970 and 2000 and whether these trends were correlated with breeding bird population trends. Of 41 species analysed, 21 showed significant increases in occurrence at garden feeders between 1970 and 2000. Many of these increases were evident only in the last 10 years. Several species showed significant positive correlations between trends in winter garden use and trends in relative population size in the previous breeding season. This was especially the case for species with population change (either increase or decrease) of the greatest magnitude. There was no evidence that seasonal shifts in garden feeder use were associated with population change in any species. Temperature was an important predictor of garden use but could not explain the year-to-year trends. However, as the number of feeding stations had increased over time the response of birds to the greater food availability in gardens may have been responsible for the widespread increases in occurrence of several species. 相似文献
964.
RICHARD B. BRADBURY ROSS A. HILL DAVID C. MASON SHELLEY A. HINSLEY JEREMY D. WILSON HEIKO BALZTER GUY Q. A. ANDERSON MARK J. WHITTINGHAM† IAN J. DAVENPORT & PAUL E. BELLAMY 《Ibis》2005,147(3):443-452
Airborne LiDAR (Light Detection and Ranging) is a remote sensing technology that offers the ability to collect high horizontal sampling densities of high vertical resolution vegetation height data, over larger spatial extents than could be obtained by field survey. The influence of vegetation structure on the bird is a key mechanism underlying bird–habitat models. However, manual survey of vegetation structure becomes prohibitive in terms of time and cost if sampling needs to be of sufficient density to incorporate fine-grained heterogeneity at a landscape extent. We show that LiDAR data can help bridge the gap between grain and extent in organism–habitat models. Two examples are provided of bird–habitat models that use structural habitat information derived from airborne LiDAR data. First, it is shown that data on crop and field boundary height can be derived from LiDAR data, and so have the potential to predict the distribution of breeding Sky Larks in a farmed landscape. Secondly, LiDAR-retrieved canopy height and structural data are used to predict the breeding success of Great Tits and Blue Tits in broad-leaved woodland. LiDAR thus offers great potential for parameterizing predictive bird–habitat association models. This could be enhanced by the combination of LiDAR data with multispectral remote sensing data, which enables a wider range of habitat information to be derived, including both structural and compositional characteristics. 相似文献
965.
Microsatellite‐containing regions were isolated and characterized in Anopheles (Nyssorhynchus) marajoara, a primary vector of malaria parasites in northeastern Amazonia, Brazil. An enrichment protocol yielded 500 positive clones. We designed primers to amplify 40 unique microsatellites, 11 of which amplified cleanly and were polymorphic. A survey of 323 individuals showed that these loci are highly variable with the number of alleles ranging from 11 to 52, and expected heterozygosity ranging from 0.64 to 0.95. These markers will be useful for studies of population structure and intraspecific variation in A. marajoara. 相似文献
966.
SIMON J. BUTLER RICHARD B. BRADBURY† MARK J. WHITTINGHAM‡ 《Journal of Applied Ecology》2005,42(3):469-476
967.
968.
Release of CO2 and uptake of O2 by Pinus resinosa Ait. pollen treated with 0, 0.004, 0.045, or 0.450 mM Cd2+ were determined manometrically. Respiration after 1.5 h was stimulated in the 0.450 mM treatment, but declined sharply after 3.5 h. CO2 evolution was inhibited more than O2 uptake. Pretreatment with Cd2+ inhibited aflization of exogenous sucrose, and conversely, exogenous sucrose did not overcome Cd2+ effects on gas exchange. Cd2+ did not act as a classical uncoupler of oxidative phosphorylation. There was no correlation of pollen germination and germ tube elongation with Cd2+ effects on gas exchange. 相似文献
969.
970.
This study was conducted to examine the effects of CO2-mediated changes in tree chemistry on the performance of the gypsy moth ((Lymantria dispar L.) and the parasitold Cotesia melanoscela (Ratz.). We used carbon-nutrient balance theory to develop hypotheses regarding changes in tree chemistry and the performance of both insects under elevated CO2. As predicted, levels of foliar nitrogen declined and concentrations of carbon-based compounds (e.g. starch and phenolics) increased under elevated CO2. Gypsy moth performance (e.g. growth, development) was altered by CO2-mediated changes in foliar chemistry, but the magnitude was small and varied across tree species. Larvae feeding on high CO2 aspen exhibited the largest reduction in performance, relative to larvae feeding on birch, oak, or maple. Parasitism by C. melanoscela significantly prolonged gypsy moth development and reduced growth rates. Overall, the effect of parasitism on gypsy moth performance did not differ between CO2 treatments. Altered gypsy moth performance on high CO2 foliage in turn affected parasitoid performance, but the response was variable: parasitoid mortality increased and adult female size declined slightly under high CO2, while development time and adult male size were unaffected. Our results suggest that CO2-induced changes in plant chemistry were buffered to the extent that effects on third trophic level interactions were weak to non-existent for the system examined in this study. 相似文献