0000000000049705

AUTHOR

Alfred Seitz

showing 41 related works from this author

Genetic and morphological differentiation ofDikerogammarusinvaders and their invasion history in Central Europe

2002

SUMMARY 1. Biological invasions often involve close taxonomic relatives either as native/invader pairs or as invader/invader pairs. Precise identification and differentiation of species is therefore of paramount importance to reconstruct the invasion history. Genetic studies are indispensable in the case of morphologically conservative taxonomic groups. 2. We analysed the Pontocaspian freshwater amphipods Dikerogammarus that have successfully invaded the benthos of large Central European rivers. Taxonomic uncertainties were clarified by phylogenetic analyses of mitochondrial 16S and COI genes. The three-way partitioning of allozyme genotypes in a syntopic population further corroborated the…

education.field_of_studybiologyPopulationZoologyDikerogammarus villosusAquatic ScienceSubspeciesbiology.organism_classificationColonisationDikerogammarus haemobaphesDikerogammarusTaxonomic rankGenetic variabilityeducationFreshwater Biology
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The influence of land use on the genetic structure of populations of the common frog Rana temporaria

1990

In order to find out the influence of land use and topographic distance on the genetic structure of populations of the common frog Rana temporaria L. in the Saar-Palatinate lowlands (Federal Republic of Germany), tissue of larvae was examined by means of horizontal starch gel electrophoresis. A total of 24 loci coding for 14 different enzymes were studied. Genotype frequencies, allele frequencies and mean heterozygosity were calculated, and genetic distances using Nei's formula. Strong deviations from the Hardy-Weinberg equilibrium were found; the degree of homozygosity was higher than expected. Separation by highways reduced average heterozygosity as well as genetic polymorphism of local p…

Loss of heterozygosityBiotopeLand useEcologyRange (biology)Genetic structureBiologyAllele frequencyEcology Evolution Behavior and SystematicsNature and Landscape ConservationRanaGenotype frequencyBiological Conservation
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Genetic structure of Cirsium palustre (Asteraceae) and its role in host diversification of Tephritis conura (Diptera: Tephritidae)

2008

Whether or not a host plant is incorporated into a phytophagous insect's diet depends on both the insect's ability to colonize the novel host and the host plant's susceptibility to the insect. The latter, again, will be influenced by the genetic structure of the host plant. Cirsium palustre (marsh thistle) is heavily infested by the tephritid fly Tephritis conura in northern Britain, whereas infestation is not only absent in southern England, but also absent on the European continent where T. conura is common on other Cirsium. To understand why regional infestation patterns evolve, we studied how genetic structure and phylogeographic ancestry of C. palustre are related to the probability of…

EcologyfungiOutcrossingBiologybiology.organism_classificationmedicine.disease_causeTephritis conuraCirsiumGenetic driftGenetic structureInfestationmedicineCirsium heterophyllumEcology Evolution Behavior and SystematicsCirsium palustreBiological Journal of the Linnean Society
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DNA Fingerprinting for the Protection of Endangered Species

1991

The main application of DNA fingerprinting is based on identity and paternity testing in man [6, 7]. In the last years it has also been increasingly used for zoological problems [2–5, 8, 10, 12, 13]. In this study DNA fingerprinting was applied for “forensics” in the field of protection of endangered species.

GeographyDNA profilingEvolutionary biologyIdentity (philosophy)media_common.quotation_subjectEndangered speciesOligomer restrictionmedia_common
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Infection of Bois-Noir tuf-type-I stolbur phytoplasma inHyalesthes obsoletus(Hemiptera: Cixiidae) larvae and influence on larval size

2009

Recent dramatic spread of the grapevine yellows disease Bois Noir (BN) in Germany is above all explained by highly increased abundances of the vector Hyalesthes obsoletus (Hemiptera: Cixiidae) associated to the plant Urtica dioica, the reservoir of the BN pathogen stolbur tuf-type-I. The vector acquires BN-phytoplasma as larvae whilst feeding on the roots of infected U. dioica. To understand the dynamics of the Urticacycle, we tested at what instar larvae become infected and whether infection affects larvae size (i.e. growth) at two sites in the Mosel Valley, Germany. Larvae were tested from infected plants and collected at instar-stages 3, 4 and 5. Larvae at stage 3 were already infected b…

Larvaanimal structuresfungiGrapevine yellowsBiologyCixiidaebiology.organism_classificationHemipteraInsect ScienceVector (epidemiology)BotanyInstarUrtica dioicaAgronomy and Crop SciencePathogenJournal of Applied Entomology
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The role of geographic setting on the diversification process among Tephritis conura (Tephritidae) host races

2006

We address the controversy over the processes causing divergence during speciation. Host races of the fruit fly Tephritis conura attack the thistles Cirsium oleraceum and Cirsium heterophyllum. By studying the genetic divergence of T. conura in areas where host plants are sympatric, parapatric and allopatric, we assessed the contribution of geography in driving host-race divergence. We also evaluated the relative importance of genetic drift and selection in the diversification process, by analysis of the geographic distribution of genetic variation. Host races were significantly diverged at five out of 13 polymorphic allozyme loci. Variance at two loci, Hex and Pep D, was almost exclusively…

SympatryPolymorphism GeneticGeographybiologyGenetic SpeciationTephritidaeAllopatric speciationCirsium oleraceumParapatric speciationbiology.organism_classificationGenetic divergenceTephritis conuraGene FrequencySympatric speciationEvolutionary biologyGeneticsAnimalsCirsium heterophyllumGenetics (clinical)Heredity
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Palaeoclimatic changes explain Anatolian mountain frog evolution: a test for alternating vicariance and dispersal events

2002

Holarctic biodiversity has been influenced by climatic fluctuations since the Pliocene. Asia Minor was one of the major corridors for postglacial invasions in the Palearctic. Today this area is characterized by an extraordinarily rich fauna with close affiliation to European, Asian and Indo-African biota. However, exact scenarios of range expansion and contraction are lacking. Using a phylogeographical approach we (i) identify monophyletic lineages among Anatolian mountain frogs and (ii) derive a spatio-temporal hypothesis for the invasion process in Anatolia. We sequenced 540 bp of the mitochondrial 16S rRNA gene from 40 populations of mountain frogs from Anatolia, the Elburz Mountains and…

MonophylyPhylogeographyHolarcticbiologyMountain frogEcologyRana macrocnemisGeneticsVicarianceBiological dispersalMolecular clockbiology.organism_classificationEcology Evolution Behavior and SystematicsMolecular Ecology
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Dispersal history of a spider (Stegodyphus lineatus) across contiguous deserts: vicariance and range expansion

2005

Israel marks a crossroads between three continents encompassing several phytogeographical and zoogeographical zones. In this complex area, the flow of species from different biogeographical regions creates opportunities to study how geographical division and colonization routes affect current distribution and structure of resident populations of organisms associated with desert and arid environments, habitats that may have persisted throughout Pleistocene glacial periods. The present paper analyses the population history of the spider Stegodyphus lineatus in the contiguous Negev and Judean deserts in Israel using allozyme and mtDNA variation. The distinct patterns of variation indicate that…

education.field_of_studyEcologyRange (biology)BiogeographyPopulationBiologybiology.organism_classificationPhylogeographyStegodyphus lineatusVicarianceBiological dispersaleducationEcology Evolution Behavior and SystematicsIsolation by distanceBiological Journal of the Linnean Society
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Effects of habitat fragmentation on the genetic structure of the monophagous butterfly Polyommatus coridon along its northern range margin

2004

Population genetic patterns of species at their range margin have important implications for species conservation. We performed allozyme electrophoresis of 19 loci to investigate patterns of the genetic structure of 17 populations (538 individuals) of the butterfly Polyommatus coridon, a monophagous habitat specialist with a patchy distribution. The butterfly and its larval food plant Hippocrepis comosa reach their northern distribution margin in the study region (southern Lower Saxony, Germany). Butterfly population size increased with host plant population size. The genetic differentiation between populations was low but significant (FST = 0.013). No isolation-by-distance was found. Hiera…

0106 biological sciences0303 health sciencesGenetic diversityeducation.field_of_studyHabitat fragmentationbiologyEcologyPopulation sizePopulation15. Life on landbiology.organism_classification010603 evolutionary biology01 natural sciences03 medical and health sciencesGenetic structureGeneticsHippocrepis comosaGenetic variabilityeducationEcology Evolution Behavior and Systematics030304 developmental biologyIsolation by distanceMolecular Ecology
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Larval distributions of the ectoparasitoid waspEurytoma robustarelative to the host tephritid gall flyUrophora cardui

2003

Parasitism may explain the patchy distributions of host populations. The present paper is a study of larval distributions of the parasitoid Eurytoma robusta in galls of the tephritid gall fly Urophora cardui . It focuses on E. robusta ’s choice of U. cardui gall and whether this changes relative to the rate of parasitism. Oviposition patterns were inferred by direct counts of larvae in galls and genetically, for both species, using indirect relatedness estimates between gall-members. Furthermore, rates of parasitism in four populations were monitored for 4 years. The modal distribution of E. robusta larvae per gall was one and independent of the level of parasitism. The mean number of E. ro…

LarvabiologyHost (biology)digestive oral and skin physiologyfungiParasitismHymenopterabiology.organism_classificationdigestive systemdigestive system diseasesEurytomidaeParasitoidfluids and secretionsInsect ScienceTephritidaeBotanyGallEcology Evolution Behavior and SystematicsEntomologia Experimentalis et Applicata
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The role of swarming sites for maintaining gene flow in the brown long-eared bat (Plecotus auritus)

2004

Bat-swarming sites where thousands of individuals meet in late summer were recently proposed as 'hot spots' for gene flow among populations. If, due to female philopatry, nursery colonies are genetically differentiated, and if males and females of different colonies meet at swarming sites, then we would expect lower differentiation of maternally inherited genetic markers among swarming sites and higher genetic diversity within. To test these predictions, we compared genetic variance from three swarming sites to 14 nursery colonies. We analysed biparentally (five nuclear and one sex-linked microsatellite loci) and maternally (mitochondrial D-loop, 550 bp) inherited molecular markers. Three m…

Genetic MarkersMalePopulationSwarming (honey bee)ZoologyDNA MitochondrialGene flowChiropteraGenetic variationGeneticsAnimalseducationGenetics (clinical)education.field_of_studyGenetic diversitybiologyEcologyGenetic VariationGene PoolSequence Analysis DNAbiochemical phenomena metabolism and nutritionequipment and suppliesbiology.organism_classificationGenetics PopulationGenetic markerbacteriaPlecotus auritusFemalePhilopatryMicrosatellite RepeatsHeredity
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Canal construction destroys the barrier between major European invasion lineages of the zebra mussel.

2002

Since the mid-1980s the zebra mussel, Dreissena polymorpha, Pallas 1771, has become the protagonist of a spectacular freshwater invasion in North America due to its large economic and biological impact. Several genetic studies on American populations have failed to detect any large-scale geographical patterns. In western Europe, where D. polymorpha has been a classical invader from the Pontocaspian since the early 19th century, the situation is strikingly different. Here, we show with genetic markers that two major western European invasion lineages with lowered genetic variability within and among populations can be discriminated. These two invasion lineages correspond with two separate na…

MalePopulation DynamicsZoologyEnvironmentDreissenaGeneral Biochemistry Genetics and Molecular BiologyPhylogeneticsGenetic variationAnimalsGenetic variabilityCrosses GeneticPhylogenyGeneral Environmental ScienceGeneral Immunology and MicrobiologybiologyEcologyGenetic VariationGeneral Medicinebiology.organism_classificationBivalviaBivalviaEuropeGenetics PopulationGenetic markerFacility Design and ConstructionZebra musselMicrosatelliteFemaleGeneral Agricultural and Biological SciencesMicrosatellite RepeatsResearch ArticleProceedings. Biological sciences
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Postgraduale Weiterbildung mit dem zertifizierten Abschluss Fachökotoxikologin/e GDCh/SETAC

2006

Environmental chemistryEnvironmental sciencePollutionUmweltwissenschaften und Schadstoff-Forschung
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Parameter Sensitivity and the Quality of Model Predictions

1994

Using SIM-PEL, a comprehensive model for the pelagic compartment of lake ecosystems, we analyse synergistic toxicant effects in lake ecosystems. We show, that — even for a rather simple model — model predictions may be strongly dependent on the time horizon of the prediction and on the quality of input parameters. For longer time spans, small errors in parameter estimation may lead to qualitatively wrong prediction of toxicant effects. Monte Carlo simulations allow to take errors in parameter estimation into account, but they need rather good estimates of parameter variance.

Quality (physics)Estimation theoryMonte Carlo methodLake ecosystemTime horizonVariance (accounting)Sensitivity (control systems)Statistical physicsQuantitative Biology::OtherPhytoplankton biomassMathematics
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Low diversity but high differentiation: the population genetics of Aglaope infausta (Zygaenidae: Lepidoptera)

2003

Aim Aglaope infausta is a thermophilous Zygaenid of Atlanto-Mediterranean origin, distributed in Portugal, Spain, France and north-western Italy reaching its north-eastern distribution limit in western Germany. The local, regional and inter-regional genetic structure of this species is studied in this analysis. Location and methods  The allozymes of 456 individuals from 12 populations (11 from western Germany and one from southern Portugal) were studied by electrophoresis. Results  Six of the 19 loci analysed were monomorphic. Genetic differentiation between populations was high (FST: 0.404), while the mean genetic diversity was low (He: 3.4%). Most (96.5%) of the genetic variance between p…

Genetic diversityEcologyChalcosiinaebiologyRange (biology)EcologyGenetic variationGenetic structureBiodiversityPopulation geneticsAglaope infaustabiology.organism_classificationEcology Evolution Behavior and SystematicsJournal of Biogeography
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Isolation and characterization of 11 polymorphic trinucleotide microsatellite markers in the stonefly Arcynopteryx compacta (Plecoptera: Perlodidae).

2011

We describe the isolation of 11 polymorphic trinucleotide microsatellite loci from the stonefly Arcynopteryx compacta. Loci were highly variable with 3 to 14 alleles (mean = 6.45). Observed heterozygosity ranged from 0 to 0.867. Seven loci showed significant deviation from Hardy–Weinberg equilibrium across both populations. There was no evidence for null alleles, and thus, Hardy–Weinberg departures could have resulted from genetic structure between populations or subpopulations. No linkage between loci was found. The 11 loci should prove highly informative for population genetic studies.

Geneticseducation.field_of_studybiologyPopulationbiology.organism_classificationNull alleleLoss of heterozygosityPerlodidaeGenetic structureGeneticsMicrosatelliteAlleleeducationMicrosatellite enrichmentEcology Evolution Behavior and SystematicsBiotechnologyMolecular ecology resources
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Performance of Host-Races of the Fruit Fly,Tephritis conuraon a Derived Host Plant, the Cabbage ThistleCirsium oleraceum: Implications for the Origin…

2008

The thistle-infesting fruit fly Tephritis conura Loew (Diptera: Tephritidae) forms host races on the melancholy thistle, Cirsium hetewphyllum (L.) Hill (Asterales: Asteraceae) and the cabbage thistle, Cirsium olemceum (L.). Scop. Previous research indicates that the host shift occurred from C. hetewphyllum to C. oleraceum. In this paper we address whether the host shift involved physiological adaptations by studying oviposition acceptance and survival of the two host races on the derived host C. oleraceum. Performance differed significantly between host races. T. conura originating from C. oleraceum produced adults in 75% of all egg-laying trials in contrast to only 6.6% in T. conura origin…

food.ingredientOvipositionPopulationCirsiumArticleHost-Parasite InteractionsTephritis conurafoodCirsiumTephritidaeBotanyCirsium heterophyllumAnimalseducationalternative hostFlavonoidseducation.field_of_studybiologyHost (biology)fungiPupaCirsium oleraceumGeneral Medicinebiology.organism_classificationAdaptation PhysiologicalfitnessspeciationLarvaInsect ScienceThistleFemaleCirsium heterophyllumperformanceJournal of Insect Science
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Invasion biology and host specificity of the grapevine yellows disease vector Hyalesthes obsoletus in Europe

2008

Within the past 10 years, the yellows disease ‘bois noir’ (BN) has become one of the commercially most important diseases of grapevine [ Vitis vinifera L. (Vitaceae)] in Europe. Infection pressure is caused by phytoplasmas of the stolbur 16SrXII-A group that are transmitted by a planthopper vector, Hyalesthes obsoletus Signoret (Homoptera: Auchenorrhyncha). Infestation happens as an accidental side-effect of the feeding behaviour of the vector, as vector and pathogen proliferation is dependent on other plants. In Germany, the increase of BN is correlated with the use of a new host plant by the vector, increase in abundance of the vector on the new host plant, and dissemination of host plant…

GeneticsbiologyHost (biology)Homopterafood and beveragesGrapevine yellowsbiology.organism_classificationPlanthopperPhytoplasmaInsect ScienceVector (epidemiology)Genetic variationBotanyCandidatus Phytoplasma solaniEcology Evolution Behavior and SystematicsEntomologia Experimentalis et Applicata
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Inheritance in the water frog Rana ridibunda Pallas, 1771 - Is it Mendelian or hemiclonal?

2008

The genome of Rana ridibunda has been detected in all known hybridogenetic water frog systems. This raises the question whether R. ridibunda is pre-adapted to reproduce hemiclonally by hybridogenesis. We allozymatically compared genotypes of primary oocytes and somatic cells of R. ridibunda females from several sites in southern France. In case of hemiclonal reproduction only one allele per locus is expected to be detectable in oocytes. However, patterns detected from oocytes of analysed females were not different from those of sexually reproducing water frogs. We therefore conclude that R. ridibunda in southern France reproduces sexually and is not pre-adapted to hemiclonal reproduction.

symbols.namesakeRana ridibundaEcologyGenotypeMendelian inheritancesymbolsZoologyLocus (genetics)BiologyAlleleEcology Evolution Behavior and SystematicsZoosystematics and Evolution
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An individual based model for the conservation of the endangered Large Blue Butterfly, Maculinea arion (Lepidoptera: Lycaenidae)

2002

Abstract European populations of the Large Blue Butterfly Maculinea arion have experienced severe declines during the 20th century, especially in the northern part of the species’ range. This endangered lycaenid butterfly needs two resources for development: flower buds of specific plants ( Thymus spp., Origanum vulgare ), on which young caterpillars briefly feed, and red ants of the genus Myrmica , whose nests support caterpillars during a prolonged final instar. In order to improve understanding of those mechanisms that are most influential to population dynamics of the butterfly, we developed a stochastic population model. This individual based model implements three main biological comp…

education.field_of_studybiologyEcologyEcological ModelingArionfungiPopulationLycaenidaebiology.organism_classificationLarge blueNestMyrmicaButterflyMyrmica sabuletieducationEcological Modelling
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Forests as dispersal barriers for Erebia medusa (Nymphalidae, Lepidoptera)

2000

Summary The nymphalid butterfly Erebia medusa is a typical species of meadows that are poor in nitrogen and fallow land. In forests, it is only found on clearings with meadow-like structures. However, it is missing on wind exposed places, too. 239 imagoes of E. medusa were sampled in the Aggtelek Karst region (north-eastern Hungary) at six different localities at the end of May 1997. The sample sizes varied between 33 and 46. The studied karst area has a typical forest steppe vegetation and is characterised by a mosaic-like distribution of meadows and forests. The sampled butterflies were analysed by allozyme electrophoresis. The level of polymorphism was significantly higher in the samples…

SatyrinaebiologyGenetic distanceEcologyErebia medusaButterflyGenetic structureBiological dispersalbiology.organism_classificationNymphalidaeEcology Evolution Behavior and SystematicsIsolation by distanceBasic and Applied Ecology
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New Polymorphic Microsatellite Loci for the Zebra MusselDreissena polymorpha(Pallas, 1771), a Common Bioindicator

2011

ABSTRACT To investigate the influence of environmental pollution on the population genetics of Dreissena polymorpha, we developed five new polymorphic micro satellite loci for the zebra mussel. This mussel is widely distributed and is a common bioindicator in the field of ecotoxicology. The amplification of the microsatellite loci was tested on a single population of 24 individuals. In this population, the number of alleles per locus ranged from 3–14, and the observed heterozygosity ranged from 0.545–0.909 (mean, 0.772). All loci followed Hardy-Weinberg expectations, suggesting no evidence for null alleles. There was no significant genetic linkage disequilibrium, neither between the aforeme…

education.field_of_studybiologyEcologyPopulationZoologyPopulation geneticsLocus (genetics)Environmental pollutionAquatic Sciencebiology.organism_classificationDreissenaZebra musselMicrosatelliteeducationBioindicatorJournal of Shellfish Research
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Morphological adaptation in host races of Tephritis conura

2007

The present study investigates morphological differentiation among host races of the fruit fly Te phritis conura Loew (Diptera: Tephritidae) for two fitness-related traits and whether these traits are host induced or genetically determined. Flies were analyzed from independent sympatric regions, and from one syntopic site where parental host plants [ Cirsium heterophyllum (L.) Hill. and Cirsium oleraceum (L.) Scop. (Cardueae)] and hybrid plants ( C. heterophyllum × C. oleraceum ) co-occur. As both host races may oviposit on hybrid plants and hybrid plants provide an identical environment for larvae of both host races, flies emerging from C. heterophyllum × C. oleraceum hybrids were used to …

Phenotypic plasticitybiologyHost (biology)fungiCirsium oleraceumbiology.organism_classificationTephritis conuraInsect ScienceTephritidaeBotanyOvipositorCirsium heterophyllumEcology Evolution Behavior and SystematicsHybridEntomologia Experimentalis et Applicata
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Isolation and characterization of 10 highly polymorphic di- and trinucleotide microsatellite markers in the mayfly Ameletus inopinatus (Ephemeroptera…

2008

We describe the isolation of ten polymorphic microsatellite loci from the mayfly Ameletus inopinatus. Loci had di- or trinucleotide repeat motifs and were highly variable with three to 17 alleles (mean = 7.15). Observed heterozygosity ranged from 0.143 to 0.905. One locus (Ami_202) showed significant deviation from Hardy–Weinberg equilibrium in one population, but no evidence for null alleles. One locus (Ami_73) was significantly linked with three other loci. The remaining nine loci should prove highly informative for population genetic studies.

Geneticseducation.field_of_studyPopulationLocus (genetics)Biologybiology.organism_classificationNull alleleLoss of heterozygosityMayflyGeneticsMicrosatelliteeducationTrinucleotide repeat expansionMicrosatellite enrichmentEcology Evolution Behavior and SystematicsBiotechnologyMolecular ecology resources
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Risk Assessment of Toxicants to Pelagic Food-Webs: A Simulation Study

1991

For a generalized mathematical model of the pelagic compartment of a lake ecosystem we show that a small variance in input parameters may result in a large variance in predicted biomasses. Since input parameters for this kind of models always show a great variance, we conclude that deterministic prediction of biomass-trajectories is rather useless and demonstrate how stochastic analysis of the model may lead to a helpful risk analysis.

Risk analysisStochastic processEcologyLake ecosystemEconometricsEnvironmental sciencePelagic zoneVariance (accounting)Risk assessment
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The significance of relatedness and gene flow on population genetic structure in the subsocial spider Eresus cinnaberinus (Araneae: Eresidae)

1998

Interdemic selection, inbreeding and highly structured populations have been invoked to explain the evolution of cooperative social behaviour in the otherwise solitary and cannibalistic spiders. The family Eresidae consists of species ranging from solitary and intermediate subsocial to species exhibiting fully cooperative social behaviour. In this study we, in a hierarchical analysis, investigated relatedness of putative family clusters, inbreeding and population genetic structure of the subsocial spider Eresus cinnaberinus. Five hierarchical levels of investigation ranging from large scale genetic structure (distances of 250 and 50 km level 1 and 2) over microgeographic structure (20 km 2 …

education.field_of_studyPopulationBiologybiology.organism_classificationEresus cinnaberinusGene flowEvolutionary biologyGenetic variationGenetic structureBiological dispersaleducationInbreedingEcology Evolution Behavior and SystematicsSocialityBiological Journal of the Linnean Society
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Parapatric diversification after post-glacial range expansion in the gall flyUrophora cardui(Tephritidae)

2010

Aim  Primary and secondary genetic clines in post-glacial colonized regions have different implications for biogeographic distributions and the origin of species. Primary clines arise in situ after colonization as adaptive responses to environmental gradients, while secondary clines are caused by contact between vicariant lineages. Here we analyse primary versus secondary origin of a genetic cline in the tephritid fly Urophora cardui in Jutland, Denmark, in a post-glacial landscape. Location  Western Palaearctic. Methods  Phylogeographic and demographic analyses of U. cardui based on mitochondrial DNA (mtDNA) genealogies, hierarchical genetic variance tests based on allozymes and distributi…

education.field_of_studyGenetic diversityEcologyRange (biology)EcologyPopulationWestern PalaearcticCline (biology)Parapatric speciationBiologyPhylogeographyEvolutionary biologyVicarianceeducationEcology Evolution Behavior and SystematicsJournal of Biogeography
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The use of Markovian metapopulation models: a comparison of three methods reducing the dimensionality of transition matrices.

2001

The use of Markovian models is an established way for deriving the complete distribution of the size of a population and the probability of extinction. However, computationally impractical transition matrices frequently result if this mathematical approach is applied to natural populations. Binning, or aggregating population sizes, has been used to permit a reduction in the dimensionality of matrices. Here, we present three deterministic binning methods and study the errors due to binning for a metapopulation model. Our results indicate that estimation errors of the investigated methods are not consistent and one cannot make generalizations about the quality of a method. For some compared o…

Population DensityMathematical optimizationeducation.field_of_studyModels StatisticalMarkov chainResearchPopulationPopulation DynamicsMarkov processPopulation processMetapopulationModels BiologicalMarkov ChainsReduction (complexity)symbols.namesakeDistribution (mathematics)symbolsQuantitative Biology::Populations and EvolutioneducationAlgorithmEcology Evolution Behavior and SystematicsCurse of dimensionalityMathematicsTheoretical population biology
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Analysis of gene flow and habitat patch network for Chazara briseis (Lepidoptera: Satyridae) in an agricultural landscape

1997

Abstract A fine geographic-scale population genetic structure analysis was performed for the endangered butterfly species Chazara briseis in the region of Halle an der Saale, Germany, for the investigation of gene flow and possible effects of habitat fragmentation on genetic variability. Patterns of genetic variance were estimated by allozyme electrophoresis and quantified with F -statistics. Levels of genetic variation were high, expected heterozygosity H e = 0.20, and mean number of alleles per locus, A = 1.93, indicating large population sizes. Butterflies inhabiting the study area probably constituted just one population and the fragmented nature of the habitat patches did not substanti…

education.field_of_studyHabitat fragmentationEcologyPopulationBiologyBiochemistryGene flowGenetic variationGenetic structureBiological dispersalGenetic variabilityeducationEcology Evolution Behavior and SystematicsIsolation by distanceBiochemical Systematics and Ecology
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Zur prognostischen Qualität komplexer Ökosystem-Simulationsmodelle

1993

Bei der Simulation okologischer Systeme besteht grose Unsicherheit bezuglich der zu verwendenden Modellparameter und Modellgleichungen. Diese Unsicherheit kann mit den prohabilistischen Methoden der Risikoanalyse in die Modellaussage integriert werden. Anhand eines Modells zur Simulation des Pelagials (Freiwassers) eines Sees (SIM-PEL) wird gezeigt, das aufgrund von nichtlinearem komplexem Systemverhalten auch die Aussagen von Risikoanalysen mit zunehmenden Prognosezeithorizont an Qualitat verlieren. Im Vergleich mit anderen Modellen zeigt sich, daJ3 bedingt durch verschiedene Modellgleichungen selbst qualitative Prognosen des Systemverhaltens nur beschrankt moglich sind.

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Phylogeographic patterns of host-race evolution in Tephritis conura (Diptera: Tephritidae)

2006

Host-race evolution is a prime candidate for sympatric speciation because host shifts must take place in the presence of both hosts. However, the geographic context in which the shift takes place may have strong allopatric or peripatric components if the primary host within a localized area is scarce or even goes extinct. Inference of the relative importance of the geographic mode of speciation may be gained from phylogeographic imprints. Here, we investigate the phylogeography of host races of the tephritid fly Tephritis conura from sympatric, parapatric and allopatric populations of Cirsium heterophyllum and Cirsium oleraceum (Asteraceae) in Europe, for addressing the age and direction, a…

SympatrybiologyfungiAllopatric speciationCirsium oleraceumPeripatric speciationParapatric speciationbiology.organism_classificationTephritis conuraSympatric speciationEvolutionary biologyGeneticsCirsium heterophyllumEcology Evolution Behavior and SystematicsMolecular Ecology
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Forensics of birds of prey by DNA fingerprinting with 32P-labeled oligonucleotide probes.

1991

Paternity tests on confiscated families of eight species of birds of prey were carried out successfully by DNA fingerprinting with 32P-labeled oligonucleotide probes. Variations in the number of hybridized fragments, depending on the species of birds, are observed using the same probe, as well as differences of polymorphism by hybridizing the DNA samples with several oligonucleotide probes.

GeneticsMaleBase CompositionBase SequenceOligonucleotideClinical BiochemistryPhosphorus IsotopesBiologyBiochemistryDNA FingerprintingAnalytical ChemistryPredationBirdschemistry.chemical_compoundchemistryDNA profilingPolymorphism (computer science)Paternity testsAnimalsBase sequenceMolecular probeOligonucleotide ProbesDNAPolymorphism Restriction Fragment LengthRepetitive Sequences Nucleic AcidElectrophoresis
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Are and bivoltine (Lepidoptera: Lycaenidae)? The discriminatory value of genetics in taxonomy

2005

Abstract Taxonomic confusion exists in several sibling species groups. The Polyommatus coridon species complex (Chalk Hill Blues) serves as a model group of sibling species in which genetic analyses provide suitable means for taxonomic clarification. We studied the allozyme patterns of the two described bivoltine species of this complex, Polyommatus hispana and Polyommatus slovacus , and compared them to the two genetic lineages of the univoltine P. coridon. P. hispana is well distinguished from P. coridon (genetic distance: 0.081), and most probably is a sibling species that has evolved during glacial isolation on the Iberian Peninsula. P. slovacus is genetically indistinguishable from the…

Genetic diversityeducation.field_of_studySpecies complexbiologyPopulationLycaenidaebiology.organism_classificationPhylogeographyGenetic distanceEvolutionary biologyPolyommatusPolyommatus hispanaeducationEcology Evolution Behavior and SystematicsOrganisms Diversity & Evolution
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The use of Markovian metapopulation models: Reducing the dimensionality of transition matrices by self-organizing Kohonen networks

2006

Abstract Markovian population models are used in conservation biology to find an accurate estimate of a population's extinction probability. Such models require handling of large transition matrices and calculations are thus extremely time-consuming when large populations have to be studied. To accomplish these problems, some authors have suggested to group together several states/sizes of the population. Unfortunately, this so-called binning frequently results in errors in estimates obtained. The main problem with binning is that it assumes that grouped states behave nearly identical with respect to the underlying stochastic population process and that so far binning methods implicitly vio…

education.field_of_studyExtinctionMarkov chainExtinction probabilityEcological ModelingPopulationMonte Carlo methodMarkov processPopulation processsymbols.namesakePopulation modelStatisticssymbolsQuantitative Biology::Populations and EvolutionStatistical physicseducationMathematicsEcological Modelling
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Differences in allozyme patterns between Diaphanosoma brachyurum and Diaphanosoma mongolianum, as revealed in Central European populations

1995

Recent taxonomic revisions in the genus Diaphanosoma have made the uncertainty in species discrimination with morphological characters obvious. Therefore species characterization on a genetic basis seems to be required. Here we examined the genetic structure of two Diaphanosoma mongolianum populations and three Diaphanosoma brachyurum populations in Central Europe by allozyme electrophoresis. A genetic differentiation between both species was evident. 5 out of 9 tested loci carried diagnostic alleles. Both species differed in their habitat choice: D. mongolianum was adapted to higher trophic levels than D. brachyurum. Co-occurrence was observed in a eutrophic lake. Populations sampled from …

biologyCladoceraEcologyGenetic structureGenetic variabilityAquatic Sciencebiology.organism_classificationDaphniaSexual reproductionGene flowTrophic levelGenotype frequencyHydrobiologia
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The genus Troglophilus Krauss, 1879 (Orthoptera: Rhaphidophoridae) in the west Balkans

2011

We present a revision of the genus Troglophilus in the western part of the Balkan Peninsula based on morphological and genetic analysis, and provide distribution data for the species. The results of these analyses reduced the number of the known taxa within the genus Troglophilus in this area to five valid species: Troglophilus cavicola (Kollar, 1833), Troglophilus neglectusKrauss, 1879, Troglophilus ovuliformisKarny, 1907, Troglophilus brevicauda Chopard, 1934, and Troglophilus lazaropolensis Karaman, 1958. A new species Troglophilus zorae sp. nov. is described and Troglophilus neglectus serbicus Maran, 1958, Troglophilus neglectus vlasinensis Maran, 1958, Troglophilus bukoviki Karaman, 19…

TroglophilusOrthopteraEcologyZoologyBiologybiology.organism_classificationTaxonTroglophilus neglectusBalkan peninsulaGenusDistribution patternAnimal Science and ZoologyEcology Evolution Behavior and SystematicsRhaphidophoridaeZoological Journal of the Linnean Society
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A molecular phylogeny of ‘true’ salamanders (family Salamandridae) and the evolution of terrestriality of reproductive modes

2009

Key innovations enable species to conquer new habitats. Within the family Salamandridae, particular adaptations to terrestrial life, such as the anatomy and physiology of the feeding apparatus, courtship behaviour and in some cases viviparity, allowed the ‘true’salamanders (genera Chioglossa, Mertensiella, Salamandra) to shift from a semi-aquatic to a more terrestrial life cycle. We sequenced 423 base pairs of the 16S RNA gene of the mitochondrial DNA for all species of the ‘true’salamanders. Based on the resulting phylogeny we discuss the evolution of terrestrial reproductive modes within this species group. We especially tested two hypotheses of monophyletic origin of specific adaptations…

SalamandridaeZoologyBiologybiology.organism_classificationMaximum parsimonyMonophylySalamandra lanzaiMertensiella caucasicaMolecular phylogeneticsGeneticsAnimal Science and ZoologySalamandraSalamandra atraMolecular BiologyEcology Evolution Behavior and SystematicsJournal of Zoological Systematics and Evolutionary Research
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Genetic and morphological differentiation in Tephritis bardanae (Diptera: Tephritidae): evidence for host-race formation

2003

The fruit fly Tephritis bardanae infests flower heads of two burdock hosts, Arctium tomentosum and A. minus. Observations suggest host-associated mating and behavioural differences at oviposition indicating host-race status. Previously, flies from each host plant were found to differ slightly in allozyme allele frequencies, but these differences could as well be explained by geographical separation of host plants. In the present study, we explicitly test whether genetic and morphological variance among T. bardanae are explained best by host-plant association or by geographical location, and if this pattern is stable over a 10-year period. Populations of A. tomentosum flies differed signific…

Phenotypic plasticitybiologyHost (biology)fungiTephritis bardanaebiology.organism_classificationArctium tomentosumGene flowEvolutionary biologyTephritidaeBotanyGenetic variationAllele frequencyEcology Evolution Behavior and SystematicsJournal of Evolutionary Biology
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Population genetic structure of the butterflyMelitaea didyma(Nymphalidae) along a northern distribution range border

1996

The population genetic structure of the butterfly Melitaea didyma was studied along the northern distribution range border in Central Germany by means of allozyme electrophoresis. Individuals were sampled from a total of 21 habitat patches from four regions, and two provinces. Sampling was designed to estimate local vs. regional differentiation. High levels of variability were found, He= 0.14-0.21. The mean expected sample heterozygosity from one region, Mosel, was significantly lower than from the Hammelburg region, He= 0.17 and 0.19, respectively. Two hierarchical levels of genetic differentiation were found. Within regions individuals sampled from different patches behaved as belonging t…

education.field_of_studybiologyEcologyRange (biology)PopulationZoologybiology.organism_classificationF-statisticsButterflyGenetic structureGeneticseducationInbreedingEcology Evolution Behavior and SystematicsMelitaea didymaIsolation by distanceMolecular Ecology
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Speciation via Differential Host–Plant Use in the Tephritid Fly Tephritis conura

2010

The close association between phytophagous insects and host plants and the possibility for specialization on new plants make phytophagous insects prime candidates for sympatric speciation via host-race evolution. In this chapter, we summarize results addressing host-race evolution in the tephritid fly Tephritis conura (Tephritidae) infesting Cirsium heterophyllum and C. oleraceum (Asteraceae). Host plant distributions in allopatry, sympatry and parapatry, and different infestation patterns enabled us to test geographic speciation scenarios, investigate adaptations, and address the importance of plant population history for diversification of T. conura.

Tephritis conuraSympatrybiologySympatric speciationEcologyTephritidaeGenetic algorithmAllopatric speciationParapatric speciationbiology.organism_classificationCirsium heterophyllum
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Comparative population genetic structures of the fruit flyUrophora carduiand its primary parasitoidEurytoma robusta

2003

The interaction between two species may depend on geographic scale and this in turn can affect co-evolution among them. The present study comparatively examines population genetic structures of the tephritid gall fly Urophora cardui and its primary ectoparasitoid Eurytoma robusta for inference of relative dispersal patterns and host parasitoid specificity. Genetic differentiation patterns indicated two levels of hierarchical structure in both species: locally similar distance-dependencies but globally differences. Locally, both species showed isolation by distance and a high correlation between host anti parasitoid F ST for the same population-pairs was found. At the local level, E. robusta…

education.field_of_studybiologyEcologyfungiPopulationPopulation geneticsCline (biology)biology.organism_classificationParasitoidColonisationInsect ScienceGenetic structureBiological dispersaleducationEcology Evolution Behavior and SystematicsIsolation by distanceEntomologia Experimentalis et Applicata
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