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

  Utökad sökning

Träfflista för sökning "AMNE:(NATURAL SCIENCES Biological Sciences) ;pers:(Bensch Staffan)"

Sökning: AMNE:(NATURAL SCIENCES Biological Sciences) > Bensch Staffan

  • Resultat 1-10 av 261
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Sigvald, Roland, et al. (författare)
  • Molecular identification of bloodmeals and species composition in Culicoides biting midges
  • 2013
  • Ingår i: Medical and Veterinary Entomology. - : Wiley. - 0269-283X .- 1365-2915. ; 27, s. 104-112
  • Tidskriftsartikel (refereegranskat)abstract
    • Investigations of host preferences in haematophagous insects, including Culicoides biting midges (Diptera: Ceratopogonidae), are critical in order to assess transmission routes of vector-borne diseases. In this study, we collected and morphologically identified 164 blood-engorged Culicoides females caught in both light traps and permanent 12-m high suction traps during 20082010 in Sweden. Molecular analysis of the mitochondrial cytochrome c oxidase subunit I (COI) gene in the biting midges was performed to verify species classification, discern phylogenetic relationships and uncover possible cryptic species. Bloodmeal analysis using universal vertebrate cytochrome b primers revealed a clear distinction in host selection between mammalophilic and ornithophilic Culicoides species. Host sequences found matches in horse (n = 59), sheep (n = 39), cattle (n = 26), Eurasian elk (n = 1) and 10 different bird species (n = 18). We identified 15 Culicoides species previously recorded in Scandinavia and four additional species haplotypes that were distinctly different from the described species. All ornithophilic individuals (n = 23) were caught exclusively in the suction traps, as were, interestingly, almost all mammalophilic species (n = 41), indicating that many biting midge species may be able to cover long distances after completing a bloodmeal. These results add new information on the composition of Culicoides species and their host preferences and their potential long-distance dispersal while blood-engorged.
  •  
2.
  • Wintersparv Stervander, Martin, et al. (författare)
  • Multiple instances of paraphyletic species and cryptic taxa revealed by mitochondrial and nuclear RAD data for Calandrella larks (Aves: Alaudidae)
  • 2016
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 102, s. 233-245
  • Tidskriftsartikel (refereegranskat)abstract
    • The avian genus Calandrella (larks) was recently suggested to be non-monophyletic, and was divided into two genera, of which Calandrella sensu stricto comprises 4-5 species in Eurasia and Africa. We analysed mitochondrial cytochrome b (cytb) and nuclear Restriction-site Associated DNA (RAD) sequences from all species, and for cytb we studied 21 of the 22 recognised subspecies, with the aim to clarify the phylogenetic relationships within the genus and to compare large-scale nuclear sequence patterns with a widely used mitochondrial marker. Cytb indicated deep splits among the currently recognised species, although it failed to support the interrelationships among most of these. It also revealed unexpected deep divergences within C. brachydactyla, C. blanfordi/C erlangeri, C. cinerea, and C. acutirostris. It also suggested that both C. brachydactyla and C. blanfordi, as presently circumscribed, are paraphyletic. In contrast, most of the many subspecies of C brachydactyla and C. cinerea were unsupported by cytb, although two populations of C. cinerea were found to be genetically distinct. The RAD data corroborated the cytb tree (for the smaller number of taxa analysed) and recovered strongly supported interspecific relationships. However, coalescence analyses of the RAD data, analysed in SNAPP both with and without an outgroup, received equally strong support for two conflicting topologies. We suggest that the tree rooted with an outgroup - which is not recommended for SNAPP - is more trustworthy, and suggest that the reliability of analyses performed without any outgroup species should be thoroughly evaluated. We also demonstrate that degraded museum samples can be phylogenetically informative in RAD analyses following careful bioinformatic treatment. We note that the genus Calandrella is in need of taxonomic revision. (C) 2016 Elsevier Inc. All rights reserved.
  •  
3.
  • Kulma, Katarzyna, et al. (författare)
  • Malaria-infected female collared flycatchers (Ficedula albicollis) do not pay the cost of late breeding
  • 2014
  • Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:1, s. e85822-
  • Tidskriftsartikel (refereegranskat)abstract
    • Life-history theory predicts that the trade-off between parasite defense and other costly traits such as reproduction may be most evident when resources are scarce. The strength of selection that parasites inflict on their host may therefore vary across environmental conditions. Collared flycatchers (Ficedula albicollis) breeding on the Swedish island Oland experience a seasonal decline in their preferred food resource, which opens the possibility to test the strength of life-history trade-offs across environmental conditions. We used nested-PCR and quantitative-PCR protocols to investigate the association of Haemosporidia infection with reproductive performance of collared flycatcher females in relation to a seasonal change in the external environment. We show that despite no difference in mean onset of breeding, infected females produced relatively more of their fledglings late in the season. This pattern was also upheld when considering only the most common malaria lineage (hPHSIB1), however there was no apparent link between the reproductive output and the intensity of infection. Infected females produced heavier-than-average fledglings with higher-than-expected recruitment success late in the season. This reversal of the typical seasonal trend in reproductive output compensated them for lower fledging and recruitment rates compared to uninfected birds earlier in the season. Thus, despite different seasonal patterns of reproductive performance the overall number of recruits was the same for infected versus uninfected birds. A possible explanation for our results is that infected females breed in a different microhabitat where food availability is higher late in the season but also is the risk of infection. Thus, our results suggest that another trade-off than the one we aimed to test is more important for explaining variation in reproductive performance in this natural population: female flycatchers appear to face a trade-off between the risk of infection and reproductive success late in the season.
  •  
4.
  • Kulma, Katarzyna, et al. (författare)
  • Malaria infections reinforce competitive asymmetry between two Ficedula flycatchers in a recent contact zone
  • 2013
  • Ingår i: Molecular Ecology. - : Wiley. - 0962-1083 .- 1365-294X. ; 22:17, s. 4591-4601
  • Tidskriftsartikel (refereegranskat)abstract
    • Parasites may influence the outcome of interspecific competition between closely related host species through lower parasite virulence in the host with which they share the longer evolutionary history. We tested this idea by comparing the prevalence of avian malaria (Haemosporidia) lineages and their association with survival in pied and collared flycatchers (Ficedula hypoleuca and F. albicollis) breeding in a recent contact zone on the Swedish island of Oland. A nested PCR protocol amplifying haemosporidian fragments of mtDNA was used to screen the presence of malaria lineages in 1048 blood samples collected during 6 years. Competitively inferior pied flycatchers had a higher prevalence of blood parasites, including the lineages that were shared between the two flycatcher species. Multistate mark-recapture models revealed a lower survival of infected versus uninfected female pied flycatchers, while no such effects were detected in male pied flycatchers or in collared flycatchers of either sex. Our results show that a comparatively new host, the collared flycatcher, appears to be less susceptible to a local northern European malarial lineage where the collared flycatchers have recently expanded their distribution. Pied flycatchers experience strong reproductive interference from collared flycatchers, and the additional impact of species-specific blood parasite effects adds to this competitive exclusion. These results support the idea that parasites can strongly influence the outcome of interspecific competition between closely related host species, but that the invading species need not necessarily be more susceptible to local parasites.
  •  
5.
  • Larsson, Kjell, 1958-, et al. (författare)
  • Population differentiation in the redshank (Tringa totanus) as revealed by mitochondrial DNA and amplified fragment length polymorphism markers
  • 2005
  • Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 6:3, s. 321-331
  • Tidskriftsartikel (refereegranskat)abstract
    • The redshank (Tringa totanus) is declining throughout Europe and to implement efficient conservation measures, it is important to obtain information about the population genetic structure. The aim of the present study was two-fold. First, we analysed the genetic variation within and between populations in the Baltic region in southern Scandinavia. Evidence of genetic structure would suggest that different populations might require separate management strategies. Second, in an attempt to study large-scale genetic structure we compared the Baltic populations with redshanks from northern Scandinavia and Iceland. This analysis could reveal insights into phylogeography and long-term population history. DNA samples were collected from six breeding sites in Scandinavia presumed to include two subspecies (totanus and britannica) and a further sample from Iceland (subspecies robusta). Two methods were used to study the population genetic structure. Domain II and III of the mitochondrial control region was analysed by DNA sequencing and nuclear DNA was analysed by screening amplified fragment length polymorphism (AFLP) markers. Mitochondrial DNA showed no variation between individuals in domain II. When analysing an 481 bp fragment of domain III seven haplotypes were found among birds. On the basis of mtDNA sequences, redshanks showed some evidence of a recent expansion from a bottlenecked refugial population. Bayesian analyses of AFLP data revealed a significant genetic differentiation between suggested subspecies but not between populations within the Baltic region. Our results indicate that populations of redshanks in Europe constitute at least three separate management units corresponding to the recognised subspecies.
  •  
6.
  • Lemke, Hilger, et al. (författare)
  • Annual cycle and migration strategies of a trans-saharan migratory songbird: a geolocator study in the great reed warbler.
  • 2013
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:10
  • Tidskriftsartikel (refereegranskat)abstract
    • Recent technological advancements now allow us to obtain geographical position data for a wide range of animal movements. Here we used light-level geolocators to study the annual migration cycle in great reed warblers (Acrocephalus arundinaceus), a passerine bird breeding in Eurasia and wintering in sub-Saharan Africa. We were specifically interested in seasonal strategies in routes and schedules of migration. We found that the great reed warblers (all males, no females were included) migrated from the Swedish breeding site in early August. After spending up to three weeks at scattered stopover sites in central to south-eastern Europe, they resumed migration and crossed the Mediterranean Sea and Sahara Desert without lengthy stopovers. They then spread out over a large overwintering area and each bird utilised two (or even three) main wintering sites that were spatially separated by a distinct mid-winter movement. Spring migration initiation date differed widely between individuals (1-27 April). Several males took a more westerly route over the Sahara in spring than in autumn, and in general there were fewer long-distance travels and more frequent shorter stopovers, including one in northern Africa, in spring. The shorter stopovers made spring migration on average faster than autumn migration. There was a strong correlation between the spring departure dates from wintering sites and the arrival dates at the breeding ground. All males had a high migration speed in spring despite large variation in departure dates, indicating a time-minimization strategy to achieve an early arrival at the breeding site; the latter being decisive for high reproductive success in great reed warblers. Our results have important implications for the understanding of long-distance migrants' ability to predict conditions at distant breeding sites and adapt to rapid environmental change.
  •  
7.
  • Tende, Talatu, et al. (författare)
  • Individual Identification and Genetic Variation of Lions (Panthera leo) from Two Protected Areas in Nigeria.
  • 2014
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:1
  • Tidskriftsartikel (refereegranskat)abstract
    • This survey was conducted in two protected areas in Nigeria to genetically identify individual lions and to determine the genetic variation within and between the populations. We used faecal sample DNA, a non-invasive alternative to the risky and laborious task of taking samples directly from the animals, often preceded by catching and immobilization. Data collection in Yankari Game Reserve (YGR) spanned through a period of five years (2008 -2012), whereas data in Kainji Lake National Park (KLNP) was gathered for a period of three years (2009, 2010 and 2012). We identified a minimum of eight individuals (2 males, 3 females, 3 unknown) from YGR and a minimum of ten individuals (7 males, 3 females) from KLNP. The two populations were found to be genetically distinct as shown by the relatively high fixation index (FST = 0.17) with each population exhibiting signs of inbreeding (YGR FIS = 0.49, KLNP FIS = 0.38). The genetic differentiation between the Yankari and Kainji lions is assumed to result from large spatial geographic distance and physical barriers reducing gene flow between these two remaining wild lion populations in Nigeria. To mitigate the probable inbreeding depression in the lion populations within Nigeria it might be important to transfer lions between parks or reserves or to reintroduce lions from the zoos back to the wild.
  •  
8.
  • Liedvogel, Miriam, et al. (författare)
  • No evidence for assortative mating within a willow warbler migratory divide
  • 2014
  • Ingår i: Frontiers in Zoology. - : Springer Science and Business Media LLC. - 1742-9994. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: In contact zones, genetic mixing of two taxa can be restricted by prezygotic (e.g. assortative mating) or postzygotic (lower fitness of hybrid offspring) barriers, or a combination of the two. A hybrid zone between two willow warbler subspecies (Phylloscopus trochilus trochilus, P. t. acredula) with distinctive migratory strategies occurs in central Sweden. These subspecies exhibit differences in migratory direction and distance, resulting in geographically distinct wintering areas in Africa. The subspecies may have diverged from a common refuge after the last ice age, and neutral genetic markers are homogeneous across their range. By contrast, several phenotypic traits and genetic markers of two chromosomal regions previously identified show steep clines across the divide. The evolutionary forces that maintain this migratory divide remain unknown. Here we use plumage colour, morphology, genetic markers and feather stable nitrogen-isotopes (delta N-15) to assess if assortative mating between migratory phenotypes could be acting as a possible mechanism for keeping the two forms genetically separate and maintaining the migratory divide. We colour-ringed a willow warbler breeding population in the central part of the hybrid zone and observed the breeding population to assess phenotypic and genotypic traits of social pairs. Results: Our data suggest that wintering area and genetic ancestry had an effect on male arrival time to the breeding grounds which could contribute to assortment. However, evidence for assortative mating could not be detected based on a comparison of plumage colour, morphology and delta N-15 between social mates. Conclusion: This finding was strengthened by analyses of subspecies-specific genetic markers, which allowed us to identify the presence of a large proportion of potential hybrids and backcrosses at the study site. Our results supported the hypothesis that pre-mating isolation in willow warblers is weak, resulting in extensive hybridisation across the migratory divide.
  •  
9.
  • Nylin, Sören, et al. (författare)
  • Embracing Colonizations : A New Paradigm for Species Association Dynamics
  • 2018
  • Ingår i: Trends in Ecology and Evolution. - Elsevier : Elsevier BV. - 0169-5347 .- 1872-8383. ; 33:1, s. 4-14
  • Tidskriftsartikel (refereegranskat)abstract
    • Parasite-host and insect-plant research have divergent traditions despite the fact that most phytophagous insects live parasitically on their host plants. In parasitology it is a traditional assumption that parasites are typically highly specialized; cospeciation between parasites and hosts is a frequently expressed default expectation. Insect-plant theory has been more concerned with host shifts than with cospeciation, and more with hierarchies among hosts than with extreme specialization. We suggest that the divergent assumptions in the respective fields have hidden a fundamental similarity with an important role for potential as well as actual hosts, and hence for host colonizations via ecological fitting. A common research program is proposed which better prepares us for the challenges from introduced species and global change. Parasites are typically assumed to be highly specialized on their hosts and well adapted to them, yet they frequently colonize new hosts - including humans, causing EIDs.This parasite paradox has caused a growing unease with the traditional assumptions in parasitology, which differ markedly from those in the field of insect-plant studies.We report the results of a workshop where parasitologists and insect-plant researchers met to explore the possibility that the two systems may be more similar than the divergent research traditions suggest, so that a common research program can be developed to better prepare us for future challenges.
  •  
10.
  • Theodosopoulos, Angela N., et al. (författare)
  • A highly invasive malaria parasite has expanded its range to non-migratory birds in North America
  • 2021
  • Ingår i: Biology letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 17:9, s. 20210271-20210271
  • Tidskriftsartikel (refereegranskat)abstract
    • Parasite range expansions are a direct consequence of globalization and are an increasing threat to biodiversity. Here, we report a recent range expansion of the SGS1 strain of a highly invasive parasite, Plasmodium relictum, to two non-migratory passerines in North America. Plasmodium relictum is considered one of the world's most invasive parasites and causes the disease avian malaria: this is the first reported case of SGS1 in wild non-migratory birds on the continent. Using a long-term database where researchers report avian malaria parasite infections, we summarized our current understanding of the geographical range of SGS1 and its known hosts. We also identified the most likely geographical region of this introduction event using the MSP1 allele. We hypothesize that this introduction resulted from movements of captive birds and subsequent spillover to native bird populations, via the presence of competent vectors and ecological fitting. Further work should be conducted to determine the extent to which SGS1 has spread following its introduction in North America.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 261
Typ av publikation
tidskriftsartikel (246)
forskningsöversikt (6)
doktorsavhandling (4)
bokkapitel (3)
konferensbidrag (1)
licentiatavhandling (1)
visa fler...
visa färre...
Typ av innehåll
refereegranskat (239)
övrigt vetenskapligt/konstnärligt (21)
populärvet., debatt m.m. (1)
Författare/redaktör
Hasselquist, Dennis (65)
Hansson, Bengt (51)
Hellgren, Olof (35)
Valkiūnas, Gediminas (29)
Åkesson, Susanne (27)
visa fler...
Westerdahl, Helena (22)
Palinauskas, Vaidas (22)
Åkesson, Mikael (17)
Peréz Tris, Javier (17)
Waldenström, Jonas (15)
Križanauskienė, Asta (15)
Zehtindjiev, Pavel (14)
Lundberg, Max (14)
von Schantz, Torbjör ... (11)
Ilieva, Mihaela (10)
Ottosson, Ulf (9)
Ellis, Vincenzo A. (9)
Liedvogel, Miriam (9)
Huang, Xi (9)
Marzal, Alfonso (8)
Sokolovskis, Kristap ... (8)
Lindström, Åke (7)
Dimitrov, Dimitar (7)
Naurin, Sara (7)
Tarka, Maja (7)
Ricklefs, Robert E. (6)
Grahn, Mats (6)
Iezhova, Tatjana A (6)
Bolshakov, Casimir V (6)
Muhammad, Asghar (6)
Hedenström, Anders (5)
Videvall, Elin (5)
Irwin, Darren (5)
Willemoes, Mikkel (5)
Jönsson, Jane (5)
Hobson, Keith A. (5)
Ciloglu, Arif (5)
Garcia-Longoria, Luz (5)
Sehgal, Ravinder N.M ... (5)
Valkiūnas, G. (5)
Tende, Talatu (4)
Larson, Keith (4)
De Lope, Florentino (4)
Sejberg, Douglas (4)
Caballero-López, Vio ... (4)
Zehtindjiev, P. (4)
Secondi, Jean (4)
Bonneaud, Camille (4)
Krizanauskiene, A (4)
visa färre...
Lärosäte
Lunds universitet (251)
Uppsala universitet (16)
Umeå universitet (8)
Karolinska Institutet (7)
Sveriges Lantbruksuniversitet (7)
Linnéuniversitetet (6)
visa fler...
Södertörns högskola (5)
Stockholms universitet (2)
Göteborgs universitet (1)
Högskolan Kristianstad (1)
Örebro universitet (1)
Chalmers tekniska högskola (1)
Karlstads universitet (1)
visa färre...
Språk
Engelska (260)
Svenska (1)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (261)
Medicin och hälsovetenskap (1)

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