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321.
JAN L. ELDRIDGE GARY L. KRAPU DOUGLAS H. JOHNSON 《The Journal of wildlife management》2009,73(2):248-252
ABSTRACT We evaluated food habits of 4 species of spring-migrant calidrid sandpipers in the Prairie Pothole Region (PPR) of North Dakota. Sandpipers foraged in several wetland classes and fed primarily on aquatic dipterans, mostly larvae, and the midge family Chironomidae was the primary food eaten. Larger sandpiper species foraged in deeper water and took larger larvae than did smaller sandpipers. The diverse wetland habitats that migrant shorebirds use in the PPR suggest a landscape-level approach be applied to wetland conservation efforts. We recommend that managers use livestock grazing and other tools, where applicable, to keep shallow, freshwater wetlands from becoming choked with emergent vegetation limiting chironomid production and preventing shorebird use. 相似文献
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A new extant family of primitive moths from Kangaroo Island,Australia, and its significance for understanding early Lepidoptera evolution
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DOUGLAS J. HILTON AXEL KALLIES LIZ MILLA JADRANKA ROTA NIKLAS WAHLBERG STEPHEN A. WILCOX RICHARD V. GLATZ DAVID A. YOUNG GLENN COCKING TED EDWARDS GEORGE W. GIBBS MIKE HALSEY 《Systematic Entomology》2015,40(1):5-16
We report the first discovery since the 1970s of a new extant family (Aenigmatineidae fam.n. ) of homoneurous moths, based on the small Aenigmatinea glatzella sp.n . from Kangaroo Island off southern Australia. It exhibits a combination of extraordinary anatomical characters, and, unlike most homoneurous moths, its larva is a conifer‐feeder (stem mining in Callitris, Cupressaceae). While the adult's mouthparts are strongly regressed, evidence from other morphological characters and from a Bayesian analysis of 25 genetic loci convincingly places the taxon among Glossata (‘tongue moths’). An unexpected tongue moth clade including Acanthopteroctetidae and Neopseustidae, suggested with low support in recent molecular analyses, remarkably becomes strongly supported when Aenigmatinea is included in the molecular analysis; the new taxon becomes subordinated in that clade (as sister group to Neopseustidae) and the clade itself appears as the sister group of all Heteroneura, representing the vast majority of all Lepidoptera. Including Aenigmatinea into the analysis thereby strengthens the surprising indication of non‐monophyly of Myoglossata, and the new phylogeny requires an additional number of ad hoc assumptions of convergence/character reversals in early Lepidoptera evolution. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:44393B52‐1889‐431A‐AB08‐6BBCF8F946B8 . 相似文献
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J. H. SUDD J. M. DOUGLAS T. GAYNARD D. M. MURRAY J. M. STOCKDALE 《Ecological Entomology》1977,2(4):301-313
Abstract. 1. A survey of 202 ha of planted forest in Langdale Forest, North Yorkshire, in 1972 discovered 326 occupied and thirty-eight deserted nests of Formica lugubris Zetterstedt. The average density of occupied nests was therefore 1.61 ha-1 .
2. Nests were associated with most crop trees and wild trees present, but were most abundant near to plantation margins and regenerating natural scrub.
3. In planted areas 76% of nests were found 5 m or less from the plantation boundary. More nests were found on the south and west border of plantations than on the north and east respectively, and most nests were not shaded from the south or southeast.
4. An analysis of nearest neighbour measurements showed that the dispersion of nests was not random but contagious (clumped). Nest mounds were higher in shaded situations than in unshaded.
5. The diameter of nest mounds was greater in areas planted with trees before 1945 than in areas planted since 1945.
6. The present population of F.lugubris appears to have spread into planted areas from nests present in marginal natural woodland which escaped the disturbance of the area at the time of planting. 相似文献
2. Nests were associated with most crop trees and wild trees present, but were most abundant near to plantation margins and regenerating natural scrub.
3. In planted areas 76% of nests were found 5 m or less from the plantation boundary. More nests were found on the south and west border of plantations than on the north and east respectively, and most nests were not shaded from the south or southeast.
4. An analysis of nearest neighbour measurements showed that the dispersion of nests was not random but contagious (clumped). Nest mounds were higher in shaded situations than in unshaded.
5. The diameter of nest mounds was greater in areas planted with trees before 1945 than in areas planted since 1945.
6. The present population of F.lugubris appears to have spread into planted areas from nests present in marginal natural woodland which escaped the disturbance of the area at the time of planting. 相似文献
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Heavy mitochondrial preparations of bean, cauliflower,and rat liver have been found to give unimodal distributionfor electrophoretic mobility against number of particles. ThepH-mean mobility curves were similar in form and consistentwith the mitochondrial surfaces being lipoproteins. de Duve (1959) separated heavy and light(lysosome-rich) mitochondrial fractions from rat liver. Microelectrophoreticstudies on similar heavy and lightmitochondrial preparations from rat liver have shown the latterto consist mostly of mitochondria with some faster-moving particlestentatively identified with de Duve's lysosomes. Lightmitochondrial preparations of bean showed no evidence of particlesadditional to mitochondria. 相似文献
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The imposition of a polyethylene glycol-induced osmotic stressof 1.5 MPa for 48 h on 28 d old Zea mays (cv. Style Pak)seedlings resulted in a 44% decreased stem dry weight and increasedtriglyceride levels in stem and leaf tissues; increased sterylester levels also occurred in stems. The magnitude of theseincreases was such that, on a dry weight basis, there were increasedtotal triglyceride and steryl ester levels in the seedlingsafter the 48 h applied stress. In stems the increased triglyceridelevel was evident in all of the component fatty acids examined,whereas in leaves it was associated mainly with one fatty acidcomponent, viz. linolenic acid (C18: 3). Changes in sterol levels were small but significant and largelyrestricted to the stem. Proline levels of all three tissuesincreased in response to water-stressing the seedlings and thegreatest increase also occurred in the stem tissues. 相似文献
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