SwePub
Tyck till om SwePub Sök här!
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "AMNE:(NATURVETENSKAP Biologi) "

Sökning: AMNE:(NATURVETENSKAP Biologi)

  • Resultat 21-30 av 78554
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
21.
  • Mikusinska, Anna, et al. (författare)
  • Quantifying landscape change during the last two centuries in Bialowieza Primeval Forest
  • 2013
  • Ingår i: Applied Vegetation Science. - 1402-2001 .- 1654-109X. ; 16:2, s. 217-226
  • Tidskriftsartikel (refereegranskat)abstract
    • QuestionWhat changes in character and extent of land use have occurred during the last 200yr in the Biaowiea Primeval Forest (BPF)? Are the landscape transformations described from the multi-temporal analysis of historical maps coherent with vegetation changes expressed by the previous palynological analyses?LocationBiaowiea Primeval Forest, PolishBelarusian border. MethodsWe used five historical maps (from 1793 to 1936) and one digital land-use map (19992000) to quantify the landscape changes. Land-use types according to historical maps were digitized and georeferenced. The maps were then used for both comparing the extent of cover types in each time step and analysing the nature of change through transition matrices. The sequence of changes concerning the proportion of land-use types was then compared with classes of pollen, which were assumed to represent corresponding vegetation types. ResultsMost of the area (>70%) has been continuously covered with forest. In the period between 1793 and 1830, the forest declined, being the main donor to agricultural land and villages. In the 20th century, the trend was reversed. We found a significant correlation between the percentage of the main vegetation types derived from historical maps and the corresponding vegetation types, as indicated by pollen, with a mean time lag of 20yr. ConclusionThe BPF landscape has been quite stable throughout the last 200yr, mainly due to the high continuity of forest cover. The results obtained from landscape analysis based on maps are coherent with pollen data collected in the same area.
  •  
22.
  • Witzgall, Peter, et al. (författare)
  • "This is not an Apple"-Yeast Mutualism in Codling Moth
  • 2012
  • Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 1573-1561 .- 0098-0331. ; 38:8, s. 949-957
  • Tidskriftsartikel (refereegranskat)abstract
    • The larva of codling moth Cydia pomonella (Tortricidae, Lepidoptera) is known as the worm in the apple, mining the fruit for food. We here show that codling moth larvae are closely associated with yeasts of the genus Metschnikowia. Yeast is an essential part of the larval diet and further promotes larval survival by reducing the incidence of fungal infestations in the apple. Larval feeding, on the other hand, enables yeast proliferation on unripe fruit. Chemical, physiological and behavioral analyses demonstrate that codling moth senses and responds to yeast aroma. Female moths are attracted to fermenting yeast and lay more eggs on yeast-inoculated than on yeast-free apples. An olfactory response to yeast volatiles strongly suggests a contributing role of yeast in host finding, in addition to plant volatiles. Codling moth is a widely studied insect of worldwide economic importance, and it is noteworthy that its association with yeasts has gone unnoticed. Tripartite relationships between moths, plants, and microorganisms may, accordingly, be more widespread than previously thought. It, therefore, is important to study the impact of microorganisms on host plant ecology and their contribution to the signals that mediate host plant finding and recognition. A better comprehension of host volatile signatures also will facilitate further development of semiochemicals for sustainable insect control.
  •  
23.
  • Zhao, Tao, 1969-, et al. (författare)
  • Fungal associates of the tree-killing bark beetle, Ips typographus, vary in virulence, ability to degrade conifer phenolics and influence bark beetle tunning behavior
  • 2019
  • Ingår i: Fungal ecology. - Amsteradam : Elsevier. - 1754-5048 .- 1878-0083. ; 38, s. 71-79
  • Tidskriftsartikel (refereegranskat)abstract
    • The bark beetle Ips typographus carries numerous fungi that could be assisting the beetle in colonizing live Norway spruce (Picea abies) trees. Phenolic defenses in spruce phloem are degraded by the beetle's major tree-killing fungus Endoconidiophora polonica, but it is unknown if other beetle associates can also catabolize these compounds. We compared the ability of five fungi commonly associated with I. typographus to degrade phenolic compounds in Norway spruce phloem. Grosmannia penicillata and Grosmannia europhioides were able to degrade stilbenes and flavonoids faster than E. polonica and grow on minimal growth medium with spruce bark constituents as the only nutrients. Furthermore, beetles avoided medium amended with phenolics but marginally preferred medium colonized by fungi. Taken together our results show that different bark beetle-associated fungi have complementary roles in degrading host metabolites and thus might improve this insect's persistence in well defended host tissues.
  •  
24.
  • Alström, Per, et al. (författare)
  • A review of the recent advances in the systematics of the avian superfamily Sylvioidea
  • 2013
  • Ingår i: Chinese Birds. - : Chinese Birds (Press). - 1674-7674. ; 4, s. 99-131
  • Tidskriftsartikel (refereegranskat)abstract
    • The systematics of the avian superfamily Sylvioidea are reviewed, focusing on studies of relationships among families and within genera, more superficially on taxonomic studies at the species level. For the families Bernieridae and Phylloscopidae, new analyses based on already published sequence data are presented. Our understanding of relationships has been vastly improved in recent years due to a large number of molecular studies. However, the relationships among the different families remain largely obscured, probably mainly as a result of rapid divergence of the different primary lineages (families). Also, species level taxonomy has been much improved in recent years due to a large number of studies applying molecular markers and/or vocalizations and other life-history data. It seems likely that the number of species will continue to increase, as new groups are being studied with modern integrative methods.
  •  
25.
  • Alström, Per, et al. (författare)
  • Dramatic niche shifts and morphological change in two insular bird species
  • 2015
  • Ingår i: Royal Society Open Science. - : The Royal Society. - 2054-5703. ; 2
  • Tidskriftsartikel (refereegranskat)abstract
    • Colonizations of islands are often associated with rapid morphological divergence. We present two previously unrecognized cases of dramatic morphological change and niche shifts in connection with colonization of tropical forest-covered islands. These evolutionary changes have concealed the fact that the passerine birds madanga, Madanga ruficollis, from Buru, Indonesia, and São Tomé shorttail, Amaurocichla bocagii, from São Tomé, Gulf of Guinea, are forest-adapted members of the family Motacillidae (pipits and wagtails). We show that Madanga has diverged mainly in plumage, which may be the result of selection for improved camouflage in its new arboreal niche, while selection pressures for other morphological changes have probably been weak owing to preadaptations for the novel niche. By contrast, we suggest that Amaurocichla's niche change has led to divergence in both structure and plumage.
  •  
26.
  • Alström, Per, et al. (författare)
  • Integrative taxonomy of the Plain-backed Thrush (Zoothera mollissima) complex (Aves, Turdidae) reveals cryptic species, including a new species.
  • 2016
  • Ingår i: Avian research. - : Elsevier BV. - 2053-7166. ; 7:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly sympatric. Methods: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic (two mito- chondrial and two nuclear markers), ecological and distributional datasets. Results: In earlier field observations, we noted two very different song types of“Plain-backed”Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China (“Alpine Thrush”); a forest breeder in the eastern Himalayas and northwest Yunnan (at least), China (“Himalayan Forest Thrush”); and a forest breeder in central Sichuan (“Sichuan Forest Thrush”). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is prob- ably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists (“Yunnan Thrush”). However, we find no consistent morphological differences from Alpine Thrush, and its breed- ing range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative “Yunnan Thrush” as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato (s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocin- cla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto (s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest Thrush. Conclusions: The Plain-backed Thrush Z. mollissima s.l. comprises at least three species: Alpine Thrush Z. mollissima s.s., with a widespread alpine breeding distribution; Sichuan Forest Thrush Z. griseiceps, breeding in central Sichuan forests; and Himalayan Forest Thrush, breeding in the eastern Himalayas and northwest Yunnan (at least), which is described herein as a new species. “Yunnan Thrush” requires further study.
  •  
27.
  • Halwachs, Bettina, et al. (författare)
  • Critical Issues in mycobiota analysis
  • 2017
  • Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 8
  • Tidskriftsartikel (refereegranskat)abstract
    • Fungi constitute an important part of the human microbiota and they play a significant role for health and disease development. Advancements made in the culture-independent analysis of microbial communities have broadened our understanding of the mycobiota, however, microbiota analysis tools have been mainly developed for bacteria (e.g., targeting the 16S rRNA gene) and they often fall short if applied to fungal marker-gene based investigations (i.e., internal transcribed spacers, ITS). In the current paper we discuss all major steps of a fungal amplicon analysis starting with DNA extraction from specimens up to bioinformatics analyses of next-generation sequencing data. Specific points are discussed at each step and special emphasis is placed on the bioinformatics challenges emerging during operational taxonomic unit (OTU) picking, a critical step in mycobiota analysis. By using an in silico ITS1 mock community we demonstrate that standard analysis pipelines fall short if used with default settings showing erroneous fungal community representations. We highlight that switching OTU picking to a closed reference approach greatly enhances performance. Finally, recommendations are given on how to perform ITS based mycobiota analysis with the currently available measures.
  •  
28.
  •  
29.
  • Olsson, Urban, 1954, et al. (författare)
  • The Lanius excubitor (Aves, Passeriformes) conundrum – Taxonomic dilemma when molecular and non-molecular data tell different stories.
  • 2010
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 55:2, s. 347-357
  • Tidskriftsartikel (refereegranskat)abstract
    • The phylogeny of 18 taxa in the Lanius excubitor complex, and the related species L. sphenocercus, L. ludovicianus and L. somalicus, was estimated based on the mitochondrial cytochrome b gene and the non-coding D-loop (in total ∼1.3 kb). According to the mitochondrial gene tree, Lanius excubitor s.l. is non-monophyletic, with some of its subspecies being more closely related to L. sphenocercus, L. ludovicianus, and L. somalicus. Also the division of the L. excubitor complex into a northern (L. excubitor) and a southern (L. meridionalis) species, as has been proposed based on morphological and ecological similarity and geographical distributions, is not compatible with the mitochondrial tree. Overall, genetic divergences among the ingroup taxa are small, indicating a recent radiation. A tree based on the nuclear ornithine decarboxylase (ODC) introns 6–7 is unresolved with respect to the ingroup, but provides strong support for a clade containing the Lanius excubitor complex, L. sphenocercus, L. ludovicianus and L. somalicus. We discuss the incongruence between the current taxonomy and the mitochondrial gene tree, and conclude that based on the latter the Lanius excubitor complex may be treated as at least six species, L. borealis, L. elegans, L. excubitor, L. lahtora, L. meridionalis, and L. uncinatus, but that other taxonomic treatments are also possible. However, uncertainty regarding to which extent the mitochondrial gene tree reflects the species phylogeny prevents us from recommending taxonomic change without further investigation. This study highlights the possible danger of relying on a single molecular marker, such as mitochondrial DNA, in taxonomic revisions and phylogenetic inference
  •  
30.
  • Šandová, Markéta, et al. (författare)
  • Relationships within Capitotricha bicolor (Lachnaceae, Ascomycota) as inferred from ITS rDNA sequences, including some notes on the Brunnipila and Erioscyphella clades
  • 2018
  • Ingår i: Mycological progress. - : Springer Science and Business Media LLC. - 1617-416X .- 1861-8952. ; 17:1-2 / S1, s. 89-101
  • Tidskriftsartikel (refereegranskat)abstract
    • DNA sequences of Capitotricha bicolor from Quercus, Fagus sylvatica, Alnus alnobetula, and Nothofagus, and C. rubi from Rubus idaeus were obtained from apothecia to establish whether specimens from different hosts belong to separate species. The obtained ITS1–5.8S–ITS2 rDNA sequences were examined with Bayesian and parsimony phylogenetic analyses. Intra- and interspecific variation was also investigated based on molecular distances in the ITS region. The phylogenetic analyses supported the specific distinctness of Capitotricha rubi and the Capitotricha from Nothofagus, but also suggest specific distinctness between samples from Quercus, Fagus, and Alnus. The interspecific distances were larger than intraspecific distances for all examined units. The smallest distance was found between the “Alnus alnobetula” and “Fagus sylvatica” units. Two new sequences of Brunnipila are published. Capitotricha, Lachnum, and Erioscyphella are compared to each other based on hair and excipulum characteristics.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 21-30 av 78554
Typ av publikation
tidskriftsartikel (57568)
doktorsavhandling (5500)
annan publikation (3189)
konferensbidrag (3149)
forskningsöversikt (2771)
bokkapitel (2596)
visa fler...
rapport (2160)
samlingsverk (redaktörskap) (694)
bok (387)
licentiatavhandling (333)
recension (136)
patent (33)
proceedings (redaktörskap) (26)
konstnärligt arbete (24)
visa färre...
Typ av innehåll
refereegranskat (59865)
övrigt vetenskapligt/konstnärligt (16644)
populärvet., debatt m.m. (1970)
Författare/redaktör
Nielsen, Jens B, 196 ... (445)
Uhlén, Mathias (319)
Kärnefelt, Ingvar (288)
Bensch, Staffan (256)
Elmberg, Johan (248)
Thell, Arne (237)
visa fler...
Björn, Lars Olof (229)
Löfstedt, Christer (216)
Hansson, Lars-Anders (203)
Olsson, Mats, 1960 (199)
Antonelli, Alexandre ... (190)
Langel, Ülo (188)
Åkesson, Susanne (184)
Hasselquist, Dennis (181)
Ellegren, Hans (178)
Hedenström, Anders (172)
Bååth, Erland (165)
Hansson, Bengt (164)
Smith, Henrik G. (164)
Bertilsson, Stefan (161)
Lindström, Åke (161)
Olsson, Lisbeth, 196 ... (159)
Larsson, D. G. Joaki ... (159)
Linse, Sara (158)
Nilsson, R. Henrik, ... (156)
Dalen, Love (155)
Nilsson, Mats (154)
Backhaus, Thomas, 19 ... (154)
Tyler, Torbjörn (154)
Ericson, Per G P, 19 ... (153)
Nilsson, Jan Åke (152)
Ericsson, Göran (152)
Nordén, Bengt, 1945 (152)
Olsen, Björn (150)
Förlin, Lars, 1950 (148)
Sand, Håkan (148)
Andersson, Leif (147)
Arup, Ulf (146)
Dupont, Samuel, 1971 (142)
Erséus, Christer, 19 ... (141)
Brönmark, Christer (140)
Waldenström, Jonas (139)
Lundeberg, Joakim (137)
Warrant, Eric (136)
Ehrlén, Johan (134)
Arnemo, Jon (133)
Johannesson, Kerstin ... (133)
Kristiansson, Erik, ... (132)
Styring, Stenbjörn (132)
Karlsson, Thomas (132)
visa färre...
Lärosäte
Uppsala universitet (15608)
Lunds universitet (14661)
Sveriges Lantbruksuniversitet (12212)
Stockholms universitet (11199)
Göteborgs universitet (10693)
Umeå universitet (6525)
visa fler...
Kungliga Tekniska Högskolan (4114)
Chalmers tekniska högskola (4108)
Karolinska Institutet (2790)
Linköpings universitet (2487)
Linnéuniversitetet (2414)
Naturhistoriska riksmuseet (1797)
Örebro universitet (1274)
Karlstads universitet (1164)
Södertörns högskola (859)
Högskolan Kristianstad (700)
Mittuniversitetet (697)
Högskolan i Skövde (388)
Högskolan i Gävle (352)
Naturvårdsverket (333)
Högskolan i Halmstad (318)
RISE (265)
Luleå tekniska universitet (210)
Malmö universitet (194)
Högskolan i Borås (170)
Havs- och vattenmyndigheten (145)
Jönköping University (126)
Högskolan Dalarna (123)
Mälardalens universitet (79)
IVL Svenska Miljöinstitutet (53)
VTI - Statens väg- och transportforskningsinstitut (42)
Gymnastik- och idrottshögskolan (38)
Handelshögskolan i Stockholm (28)
Riksantikvarieämbetet (17)
Högskolan Väst (13)
Marie Cederschiöld högskola (11)
Blekinge Tekniska Högskola (6)
Röda Korsets Högskola (6)
Försvarshögskolan (4)
Institutet för språk och folkminnen (2)
Nordiska Afrikainstitutet (1)
Sophiahemmet Högskola (1)
Enskilda Högskolan Stockholm (1)
visa färre...
Språk
Engelska (73342)
Svenska (4829)
Tyska (95)
Norska (66)
Danska (37)
Spanska (35)
visa fler...
Franska (28)
Kinesiska (22)
Ryska (16)
Odefinierat språk (16)
Finska (14)
Portugisiska (9)
Japanska (8)
Polska (7)
Nederländska (6)
Arabiska (6)
Persiska (5)
Isländska (2)
Katalanska (2)
Latin (1)
Italienska (1)
Estniska (1)
Turkiska (1)
Slovakiska (1)
Koreanska (1)
Vietnamesiska (1)
visa färre...
Forskningsämne (UKÄ/SCB)
Naturvetenskap (78492)
Medicin och hälsovetenskap (6240)
Lantbruksvetenskap (5285)
Teknik (2280)
Samhällsvetenskap (1358)
Humaniora (798)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy