ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Drosophila melanogaster  (138)
  • Springer  (138)
  • 2025-2025
  • 1980-1984  (71)
  • 1975-1979  (67)
  • 1950-1954
Sammlung
Schlagwörter
Erscheinungszeitraum
Jahr
  • 101
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 59 (1981), S. 251-263 
    ISSN: 1432-2242
    Schlagwort(e): Drosophila melanogaster ; Rare allele ; Dynamic behaviour ; Asymmetrical selection response ; Changes in heritability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary An initially rare allele with a large effect on a quantitative character is expected to exhibit the following behaviour in artificial selection lines: 1. It should change in frequency, or be lost by chance, at rates predictable from the effects of the allele on the quantitative character and the selection regime imposed. 2. At the phenotypic level the behaviour of the allele should cause (a) asymmetrical responses to bidirectional selection, (b) variation among replicate lines in response to selection corresponding to the behaviour of the allele in individual lines, (c) changes in heritability in lines in which the allele increases in frequency and (d) selection response compatible with the effects of the allele. This paper reports an experimental evaluation of these predictions utilizing a rare allele of large effect (sm lab ) detected in a sample of the Canberra outbred population of Drosophila melanogaster at a frequency of 1/120. Homosygosity for this allele reduced abdominal bristle number by more than 50%, altered the abdominal bristle pattern and reversed the sexual dimorphism for abdominal bristle number. Experiments were done to characterise sm lab and all evidence indicates that it is a single allele with a very large effect. Bidirectional selection for abdominal bristle number was carried out in three high and three low lines from this sample of the Canberra population. The sm lab allele rose in frequency and went to fixation in two of the low lines (in 10 generations) but was lost from the third. These times to fixation were slower than the expectations derived from computer simulations of the behaviour of such an allele but this can be attributed to the lower fitness of sm lab homozygotes. The proportions of lines with the allele fixed or lost were compatible with expectations. At the phenotypic level, the behavior of sm lab had the expected consequences, namely, (i) asymmetrical responses to bidirectional selection, (ii) variation in response among replicate low lines corresponding to the behaviour of sm lab , (iii) changes in heritabilities in the lines in which sm lab went to fixation, and (iv) selection responses compatible with the effects of the allele. A test for rare alleles of large effect was proposed, based on the expected pattern of change in heritability under artificial selection. This test was applied to the high selection lines but no evidence was found for important effects due to rare alleles of large effect increasing abdominal bristle number, a conclusion consistent with other independent evidence. This work provides experimental corroboration of the links between population genetics and quantitative genetics.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 102
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 62 (1982), S. 289-293 
    ISSN: 1432-2242
    Schlagwort(e): Interocellar bristles ; Drosophila melanogaster ; Disruptive selection ; Mating system
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary A population of Drosophila melanogaster has been exposed to disruptive selection for interocellar bristle number for fifteen generations. Two different mating systems have been employed: quasi-random and mating-choice. The expected results of an increase in phenotypic variance and divergence of extreme mating groups were not found when the mating-choice system was used, while a clear divergence (2.04% of overlap) was found at the end of the experiment in one line where the quasi-random system (QR1) had been used. A possible explanation for our results, which is also suggested by those of several other authors, could be that of hybrid vigor. Thus, the reason for the absence of effect in MCh may be that the progeny of “hybrid” matings are likely to be less inbred and therefore have higher viability, mating ability and egg production.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 103
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 66 (1983), S. 221-223 
    ISSN: 1432-2242
    Schlagwort(e): Artificial selection ; Selection plateau ; Accumulation of lethals ; Sternopleural bristle number ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Four synthetic lines of D. melanogaster selected for low sternopleural bristle number for 50 generations were screened for lethals on chromosome III when their mean score equalled 2.5. Each line originated from a cross between line M (previously selected for the same trait during 130 generations) and a different unselected cage population. Line M was already known to carry a recessive lethal on chromosome III affecting the selected trait, such that the bristle score of the lethal heterozygote was lower than that of the viable homozygote. Tests revealed 18 lethals, 15 of these present in at least two lines. Each line carried from 10 to 16 lethals. All lines carried groups of lethals present on the same chromosome, and at least six lethals in each line were included in such an association with a frequency of 0.18 or higher. It appears that the lethal affecting bristle score in line M has protected a segment of chromosome III from natural selection and that the remaining 14 lethals have accumulated later in that line.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 104
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 56 (1980), S. 161-173 
    ISSN: 1432-2242
    Schlagwort(e): Drosophila melanogaster ; Chromosome ; Spontaneous interchange ; half-translocation ; Non-homologous pairing ; Mitosis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Herein is described an attempts to establish chromosome pairing-interchange relationships in Drosophila melanogaster female. For this purpose, the formation of half-translocations was studied in XXY and XX females bearing compounds of the second pair of autosomes. With respect to XXY females, it was expected that the free Y chromosome would pair with these compounds and that half-translocations involving 2L would arise. In as much as compound chromosomes in XX females had no partner for pairing, the formation of half-translocations involving 2L was not expected. Half-translocations were registered in the F1 from crosses of XX and XXY females to b j pr cn/T(Y;2)C males. The cross was designed to permit the detection of very rarely occurring non-homologue interchanges. Offspring number was 335 in XX females and 550 in XXY females. The majority of offspring consisted of individuals arisen from the spontaneous restitution of compounds and the formation of 2n egg cells. Based on phenotype, the offspring of XX females contained 4 individuals with half-translocations involving 2L; there were 48 such flies among the offspring of XXY females. As confirmed by progeny analysis, 38 half-translocations occurred in XXY females and none in XX females. Of the 31 spontaneous interchanges in XXY females 28 were recorded between the Y and the left compound, one between the Y and the right compound, and one between the X and the left compound. Non-homologue interchanges were of oogonial origin judging by the fact that individuals with half-translocations arose in clusters. Unlike Y — left compound interchanges, the interchanges between autosomal compounds seem to be of meiotic origin.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 105
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 57 (1980), S. 25-32 
    ISSN: 1432-2242
    Schlagwort(e): Long-term selection ; Residual genetic variability ; Heritability ; Abdominal bristle number ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Six replicate lines of Drosophila melanogaster, which had been selected for increased abdominal bristle number for more than 85 generations, were assayed by hierarchical analysis of variance and offspring on parent regression immediately after selection ceased, and by single-generation realised heritability after more than 25 generations of subsequent relaxed selection. Half-sib estimates of heritability in 5 lines were as high as in the base population and much higher than observed genetic gains would suggest, excluding lack of sufficient additive genetic variance as a cause of ineffective selection in these lines. Also, there was considerable diversity among the six lines in composition of phenotypic variability: in addition to differences in the additive genetic component, one or more of the components due to dominance, epistasis, sex-linkage or genotype-environment interaction appeared to be important in different lines. Even after relaxed selection, single-generation realised heritabilities in four lines were as high as in the base population. As a large proportion of total genetic gain must have been made by fixation of favourable alleles, the compensatory increase of genetic variability has been sought in a genetic model involving genes at low initial frequencies, enhancement of gene effects during selection and/or new mutations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 106
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 57 (1980), S. 113-117 
    ISSN: 1432-2242
    Schlagwort(e): Long-term selection ; Relaxed selection ; Reverse selection ; Dominance of bristle number genes ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Reverse and relaxed selection were carried out in sublines which were derived from six replicate lines of Drosophila during 86–89 generations of selection for increased abdominal bristle number, and the reverse selection sublines were reciprocally crossed with selection lines of their origin. The results of serial relaxed selection initiated at different generations of selection confirm that the accelerated responses observed in the selection lines were largely due to deleterious genes, particularly lethals, with large effects on the selected character. The decline in mean bristle number under relaxed selection was not much different between crowded and uncrowded relaxed sublines. Reverse selection initiated at generation 57 was very effective, though it failed to bring the mean back to the base population level, and the genetic differences between replicate sublines (two from each of the six lines) indicate that low bristle number genes were probably rare in the selection lines. The genes which were still segregating after 57 generations of selection, on the average, did not show any directional dominance. The contribution of the X-chromosome to selection response was proportional to its chromosome length.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 107
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 57 (1980), S. 247-255 
    ISSN: 1432-2242
    Schlagwort(e): Compound ; free-arm strains ; Drosophila melanogaster ; Unstable genetic isolation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Crosses between compound-2L; free-2R (free-arm) and standard strains of Drosophila melanogaster produce two classes of inviable aneuploid hybrids in equal proportions: monosomic 2L and trisomic 2L. The lethal period for monosomics occurs during embryogenesis while the trisomics survive to late pupae. Since the hybrids are inviable, standard and free-arm strains within a mixed population remain genetically isolated. Genetic isolation in the absence of mating isolation offers an extreme example of unstable equilibrium. Relative fitness data indicate that an unstable equilibrium will be established between free-arm and standard strains at a ratio of 2.5∶1. Indeed, in three cage experiments established at initial ratios of 3∶1, free arms to standards, laboratory (Oregon R) or native (Okanagan S) standard strains were completely replaced in approximately 100 days by free-arm lines derived either from laboratory or from native genetic background. In contrast, one cage established at an initial ratio of 4∶1 failed to show replacement and for 92 days remained at approximately the initial ratio. Subsequent genetic analysis of flies removed from this cage identified the presence of an anomalous strain through which genetic information was transferred reciprocally between the free-arm and standard lines. The second chromosomes carried by this strain consisted of a free-2R and a standard second on the right arm of which was attached a duplication for all of 2L. While the origin of the 2L·2R+2L chromosome was uncertain, genetic and cytological examinations revealed that it represented the reciprocal crossover product expected from an exchange that generated a F(2R). Additional crosses disclosed that the transmission frequency of the asymmetrical pair of second chromosomes, as well as their right-arm crossover products, was disproportionately in favor of the short arm. Since unequal transmission was invariably greater from female parents, this phenomenon was viewed as further evidence in support of the drag hypothesis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 108
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 60 (1981), S. 317-327 
    ISSN: 1432-2242
    Schlagwort(e): Artificial selection ; Selection for wing length ; Correlated responses to selection ; Allozyme systems ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Significant changes of genotypic structure in 20 lines selected for wing length are detected by analysis of the allelic frequencies of several enzyme loci (XDH, LAP-D, EST-6, 1-APH, ADH, α-GPDH). These changes are not haphazard but a consequence of the effects of selection on the genetic structure of the population, since replicate lines always behave in a parallel way. The changes are larger in the lines selected for short wings, in which the genetic variability decreases considerably. This decrease is the result of selection for homozygosity, detected at the allozyme loci, but most probably reflects homozygosity of more or less extended chromosomal segments. Selection for wing length, especially for short wings, favoured recombinants of the initial founder chromosomes. Only in the 1-APH and the EST-6 loci, separated by 11.7 centimorgans on the genetic map, do the alleles linked in the founder lines change in parallel in the control and long wing lines. The correlated response in the allozyme allele frequencies cannot be accounted for by a direct influence of the allozymes on the variability in wing length. The changes in the EST-6, 1-APH and perhaps in the LAP-D, can be explained by a direct effect of natural selection on the allozyme loci, probably in interaction with the effect of selection for wing length on linked loci. This last effect seems to be the main factor contributing to the change detected in the XDH locus.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 109
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 62 (1982), S. 89-96 
    ISSN: 1432-2242
    Schlagwort(e): Population genetics ; Drosophila melanogaster ; Multiple mating ; Alcohol dehydrogenase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Mother-offspring data for alcohol dehydrogenase genotypes of a vineyard cellar population of D. melanogaster are best explained by a model that allows 21% of females in the population to mate twice with an 83% level of sperm displacement. A population model with multiple mating and sperm displacement is examined theoretically. A formula for the effective population size is derived under this model. Multiple mating increases the effective population size relative to single mating.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 110
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 279-288 
    ISSN: 1432-0878
    Schlagwort(e): Nucleoli ; Fibrillar centres ; Chromatin ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In embryonic cell-line derivative KCo of Drosophila melanogaster, the nucleolus, like most nucleoli, contains a small proportion of ribosomal DNA (1–2% of the total nucleolar DNA). The ribosomal DNA is virtually the only active gene set in the nucleolus and is found among long stretches of inactive supercoiled heterochromatic segments. We have demonstrated by use of a Feulgen-like ammine-osmium staining procedure that, depending on the state of growth, more or less fibres of decondensed DNA emanating from the intra-nucleolar chromatin (which is in continuity with the nucleolus-associated chromatin) ramify and unravel within the central nucleolar core to be transcribed. The nucleolus expands or contracts with the variation of activity and could belong to a supramolecular matricial structure such as is shown after extraction of the nuclei. After a long period of exposure to high doses of actinomycin D, the central nucleolar core became an homogeneous fibrous structure that could be interpreted as an aggregate of protein skeletal elements. The mechanism of repression and derepression of the nucleolar chromatin could thus be explained by a mechanism involving in part a sub-nucleolar structure. We propose a schematic organization of the nucleolar chromatin in KCo cells of Drosophila and discuss it in relation with other nucleolar organizations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 111
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 216 (1981), S. 513-523 
    ISSN: 1432-0878
    Schlagwort(e): Internal taste sensilla ; Sensory projections ; Cobalt diffusion ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Phase-contrast microscopy of 2.5 μm plastic sections reveals five different kinds of sense organs on the internal mouthparts of Drosophila melanogaster: a ventral group of sensilla on the epipharynx, three kinds of sense organs in the middle part of the sucking apparatus (the cibarium), one of them being described here for the first time, and an additional type of sensillum in the dorsal pharynx (Fig. 1). Three of these internal sense organs resembling each other structurally form similar projection patterns in the tritocerebrum, whereas external taste receptors on the labial palps show a different pattern in the suboesophageal ganglion (Fig. 12). The central projections of these internal and external sensilla were traced by applying an ethanolic solution of cobalt on the intact cuticle.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 112
    ISSN: 1573-3297
    Schlagwort(e): mating success ; allozyme polymorphism ; overdominance ; mating latency ; Adh locus ; Drosophila melanogaster ; rare genotype mating advantage ; alcohol dehydrogenase ; statistical methods
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Strains ofDrosophila melanogaster having different alcohol dehydrogenase (Adh) genotypes (FF, FS, or SS) were assembled in a mating chamber in varying ratios, and the mating successes were recorded. In experiments with a 25∶25 ratio, theFF males succeeded in mating more than didFS andSS males, while theFS males surpassed theSS males. As for the females,FF also surpassedSS. In experiments with a 5∶45 or 45∶5 ratio, some differences from the 25∶25 ratio occurred, but in these cases the rare genotypes were at a disadvantage. In one case, female genotypes (FF vs.SS) displayed a difference in mating latency time, but male genotypes did not. The findings did not suggest that rare genotype mating advantage and overdominance in mating success play a role in the maintenance of theAdh polymorphism.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 113
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 10 (1980), S. 291-302 
    ISSN: 1573-3297
    Schlagwort(e): foraging strategies ; chromosomal analysis ; Drosophila melanogaster ; larvae ; feeding-locomotor behavior
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Two larval foraging strategies inDrosophila melanogaster were identified, “rover” and “sitter.” “Rovers” traverse a large area while feeding whereas “sitters” cover a small area. The difference between “rovers” and “sitters” was analyzed genetically by chromosomal substitutions between isogenic stocks. Differences in larval locomotor behavior (“crawling behavior”) can be attributed to the second chromosome, the “rover” strategy being dominant over the “sitter” strategy. Differences in feeding rate (“shoveling behavior”) are affected additively by both the second and third chromosomes. Natural populations ofDrosophila larvae were sampled three times over a 2-month period; “rovers” and “sitters” were at constant frequencies in these populations. The two foraging strategies are discussed in the light of resource utilization in environments where food is distributed continuously or discontinuously.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 114
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; esterase 6 activity ; esterase 6 ; null allele ; remating ; fitness
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Esterase 6 (EST 6) inDrosophila melanogaster is a male reproductive enzyme transferred to females as a component of the seminal fluid [Richmond, R. C., Gilbert, D. G., Sheehan, K. B., Gromko, M. H., and Butterworth, F. W. (1980).Science 207:1483–1485]. Here we report investigations into the relation between EST 6 and remating by females. EST 6 activity in a strain selected for decreased time to remating is increased over control levels. Inseminated females remated to males carrying null or active alleles show no differences in the timing of remating. However, females inseminated by EST 6-active males remate significantly sooner than females inseminated by null males. Interrupted copulation experiments demonstrate that the remating effect is not due to EST 6 alone but requires other components of the ejaculate. Other evidence suggests that sperm stored in the ventral receptacle respond to EST 6 levels and control remating time. As the first mate of a female who will remate, null-EST 6 males have, under laboratory conditions, a significantly higher fitness than males carrying active alleles. Thus the absence of null alleles of EST 6 in natural populations presents a dilemma suggesting that the remating effect of EST 6 may be balanced by other effects on reproduction.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 115
    ISSN: 1432-0878
    Schlagwort(e): Antennal sensilla ; Central projections ; Antennal glomeruli ; Orthograde cobalt diffusion ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Cobalt fills from small, defined regions of the antenna in D. melanogaster show that the three types of sensilla on the third segment, the flagellum, and a fourth sensillum located in the arista, project into the glomeruli of the antennal lobe. We have identified 19 glomeruli in each lobe, according to their location, shape, and size. At least ten of these represent major projection areas of flagellar or aristal sensilla. The large majority of glomeruli is innervated from both antennae, but a small group of five receive exclusively ipsilateral input. A particular sensory fiber appears to terminate only in one specific glomerulus, either in the ipsilateral or in both lobes. Fills from flagellar regions bearing a single type of sensillum, yield a specific pattern of glomeruli containing stained terminals. Aristal projections remain strictly ipsilateral, whereas those from the other sensilla consist of an ipsilateral and a bilateral component. When filling from different points in an area bearing one type of sensillum, similar projections are produced, suggesting that projection patterns observed reflect predominantly the type of sensillum rather than its location on the flagellum. Accordingly, individual glomeruli might represent functional units, each receiving antennal input in a characteristic combination.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 116
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 8 (1978), S. 53-64 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; geotaxis ; chromosome analysis ; dominance effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Positive and negative geotactic maze behaviors were selected in strains of Drosophila melanogaster, for over 40 generations on 15-unit classification mazes. A chromosome substition analysis of these behaviors was undertaken to determine which of the three major chromosomes is most important in causing the differences in geotactic maze behavior between the divergent strains. By following the appropriate mating scheme, every possible homozygous chromosomal combination of the X, II, and III chromosomes from the geopositive and geonegative strain was produced. Heterozygous combinations were also produced to test for dominance and interchromosomal interactions. The results indicate that all three chromosomes are involved in geotactic behavior. The order of importance was II〉III〉X. Dominance effects were found in females for the X chromosome from the geopositive strain and for the III chromosome from the geonegative strain. No evidence for interchromosomal interactions was uncovered.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 117
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 123-128 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; phototaxis ; X chromosome
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Strains ofDrosophila melanogaster differ in their phototactic responses to red light (654 nm). Genes located on all three major chromosomes are involved in influencing the response, but the X chromosome and third chromosome account for most of the variation in phototaxis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 118
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 129-134 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; D. simulans ; larval feeding behavior ; egg-to-adult viability ; isofemale line
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Larval feeding behavior of isofemale lines of the sibling speciesDrosophila melanogaster andD. simulans was investigated. This behavior was measured as the number of cephalopharyngeal retractions of individual larvae per 30 sec period (CPR score) in different generations (G0, G1, and G14). In addition, egg-to-adult viability was estimated in each isofemale line. The results were as follows: (1) In either species, there was variation of CPR score among individuals and among isofemale lines. Although no differences of CPR score were found among experimental groups (generations) and between species, there was a significant difference among isofemale lines. (2) The behavioral trait was stable through generations in each isofemale line. (3) This behavior was correlated with egg-to-adult viability, showing that it is important for the development of the fly.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 119
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 209-217 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; D. simulans ; D. pseudoobscura ; pupation height ; geotaxis ; species differences ; selection for pupation height
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Pupation heights of various natural and laboratory populations ofDrosophila melanogaster, D. simulans, andD. pseudoobscura were observed in the laboratory under conditions of continuous darkness or continuous light. Generally higher mean pupation heights were observed under conditions of darkness.D. melanogaster tended to pupate higher than theD. pseudoobscura populations, andD. pseudoobscura tended to pupate higher thanD. simulans. The order of these species differences was similar whether pupation was measured in light or in darkness. Results of selection for pupation height inD. melanogaster suggest the presence of genetic variation for this character. The possibility that a relationship exists between adult and larval behaviors was explored by measuring the pupation heights of larvae from strains selected for geotactic behavior as adults, and also by measuring geotaxis of adults from strains selected for pupation height.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 120
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 257-275 
    ISSN: 1573-3297
    Schlagwort(e): sexual behavior ; Drosophila melanogaster ; genetic mosaics ; ontogeny of behavior ; wing vibration
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The sex appeal of aDrosophila melanogaster female is defined here as the stimulus (or set of stimuli) which induces wing vibration in courting males. A quantitative measure of sex appeal is the cumulative duration of wing vibration induced by a given female averaged over several consecutive test intervals using different standardized male testers (sex appeal parameter, SAP). By use of SAP, both males and females are found to have the same amount of sex appeal on the first day after eclosion. However, males rapidly lose it by the next day, so that mature males become distinct from females. We report the ontogeny of the male's response to sex appeal. By the SAP method, we also demonstrate that the male's response is dependent on his previous encounter with females. The sex appeal of 287 gynandromorphs was examined in order to localize the sex appeal focus by means of blastoderm fate mapping. Most mosaic flies were classified as either positive (femalelike, with high SAPs) or negative (malelike, with SAPs of zero). Sixteen percent of the gynandromorphs had intermediate levels of SAP, inducing only short vibrations, a response which males rarely give to normal females. Assuming that the gynanders with such intermediate sex appeal must have both female and male foci, distances to the foci from external landmarks were calculated. The center of the focus seems to be an internal structure mapping to the ventroposterior region of the blastoderm fate map, close to the primordia of the anterior sternites. The focus might include a large mesodermal area, but only part of it must have a female genotype for the sex appeal to be expressed. A possible involvement of the fat bodies in production of the sex appeal stimulus is discussed in relation to these findings. Consistent with this conclusion is the fact that females whose abdomens were amputated still retain enough sex appeal to induce male wing vibrations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 121
    ISSN: 1573-3297
    Schlagwort(e): aristal morphology ; Drosophila melanogaster ; artificial selection ; geotaxis ; mating behavior
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The aristae ofDrosophila have been shown to play a role in mating behavior and geotaxis. Two populations ofD. melanogaster were selected for increased and decreased numbers of major aristal branches. Selection was successful and resulted in two lines differing by an average of six aristal branches. Hybridization analyses of selected lines revealed that genes influencing aristal branching are located on both the X chromosome and the autosomes. Polygenic control of aristal morphology is indicated by a gradual response to selection and low realized heritabilities. When selection was relaxed for 19 generations, the number of aristal branches did not revert to the number in the control line. Changes in aristal branching did not appear to have a consistent influence on geotaxis, although there was a tendency for flies with fewer aristal branches to be geonegative. Neither mating speed nor ethological isolation between the two populations was affected by selection. It is concluded that the number of aristal branches inDrosophila is a neutral trait (i.e., not subject to natural selection) under laboratory conditions. Correlations between aristal morphology and behavior found in other selection experiments by previous investigators were likely due to linkage disequilibria.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 122
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 407-412 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; oviposition site preference ; substrate temperature ; heritability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Drosophila melanogaster females from a multifemale stock (SC-1) showed strong oviposition site preference (OSP) in a continuous gradient of substrate temperatures (18–31°C). Flies reared at 25°C had an OSP ( $$\bar X$$ ±SE) of 25.2±0.2°C, whereas flies reared at 18°C had an OSP of 23.5±.2°C. Flies reared from egg to adult at one temperature and exposed as adults for 4 days to another temperature had OSPs intermediate between these extremes. This second 4-day exposure seemed to have a greater effect on OSP than the first rearing temperature. Selection experiments failed to produce significant change in mean OSP in eight generations, indicating a low heritability of temperature OSP in this stock.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 123
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 425-429 
    ISSN: 1573-3297
    Schlagwort(e): random mating ; Drosophila pseudoobscura ; pheromones ; Drosophila melanogaster
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Inbreeding, up to 12 generations of single-pair matings, did not cause significant deviation from random mating among two sets of strains inDrosophila pseudoobscura. This contrasts with reports that inbreedingD. melanogaster induces negative assortative mating among lines.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 124
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 543-553 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; divergent selection ; locomotor activity ; heritability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Selection for high and low locomotor activity has been applied in two base populations ofDrosophila melanogaster of distinct geographical origin. From each base population a high and a low line were selected, in which anesthesia was performed with ether. In addition, from one of the base populations a high line and a low line were selected under CO2 narcosis. Locomotor activity was measured in an apparatus consisting of rows of 20 tubes in a line. Heritabilitities in the base populations determined in progeny tests were approximately 10%. Divergent directional selection was successful with realized heritabilities of similar value.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 125
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 555-561 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; locomotor activity ; mating preference ; sexual isolation ; fertility ; selected lines
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Tests for reproductive isolation between lines selected for locomotor activity were performed. Three sets of selection lines were used, each consisting of lines selected for low and high locomotor activity from the same base population. Females preferred high-activity males in almost every case. However, in one of the sets temporary sexual isolation was found between flies of the high and low lines. This was accompanied in the low-activity females with a higher fertility when they were mated with their own males. After further selection the partial isolation disappeared.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 126
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 9 (1979), S. 563-570 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; locomotor activity ; genetic analysis ; X chromosome ; selected lines
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Divergent directional selection produced three pairs of lines each consisting of a line with high and a line with low locomotor activity. Reciprocal crosses between the high and low lines of one of these pairs showed that a considerable part of the activity differences was contributed by differences between the X chromosomes. This was confirmed by a substitution of the three large chromosomes, between the low and the high lines. The two large autosomal chromosomes had only minor effects. Interactions between chromosomes were sometimes significant. Low-activity alleles tended to be dominant over alleles for high activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 127
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 5 (1975), S. 395-404 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; Drosophila simulans ; hybrids ; sexual behavior
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Courtship song and mating speed of hybrids betweenDrosophila melanogaster andD. simulans were investigated. The courtship song of hybrid males is identical to that ofD. simulans, suggesting that X chromosome determination, known from the cross betweenD. pseudoobscura andD. persimilis, is also possible here. Wingbeat frequency of hybrids is intermediate between that of the two parents, demonstrating that courtship song and wingbeat frequency are inherited independently of each other. In mating tests, hybrid males court and are accepted byD. simulans females more than hybrid females (presumably because their song is more “acceptable” to the former).D. melanogaster females reject hybrid males. Hybrid females acceptD. melanogaster males readily, hybrids less readily, andD. simulans least.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 128
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 6 (1976), S. 161-170 
    ISSN: 1573-3297
    Schlagwort(e): behavioral phenotype ; mating speed ; assortative mating ; Drosophila melanogaster ; progeny
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Time to copulation was measured in matings within and between two inbred Drosophilamelanogaster strains, Edinburgh (E) and 6C/L, using groups of one or five flies of each sex. The E males, which mated faster, usually mate with E females, which are less likely to be fertilized and have fewer progeny whose adult viability is lower. Although generally E males mated far faster with E females than did 6C/L males, there was no difference between the males when with 6C/L females. This need not imply any mating discrimination by E females, but only differences between the strains in the use of preening as a general repulsion movement toward other flies. It is suggested that a greater variety of behavioral and other characteristics (the “behavioral phenotype”) should be considered in studies of mating speed and assortative mating, especially where mating speed is being considered as a major component of fitness.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 129
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 6 (1976), S. 385-389 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; data analysis ; mating speed ; truncated distributions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The distribution of mating speeds in wild-typeDrosophila melanogaster is shown to be log normal. The analysis of mating speeds by methods for truncated distributions is validated, and unbiased estimates of the mean mating speed, the variance of mating speed, and the proportion of flies capable of ever mating are produced. In pair matings, not all pairs are capable of copulating, given even a 7-day mating period.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 130
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 6 (1976), S. 407-420 
    ISSN: 1573-3297
    Schlagwort(e): chemical attractant ; Drosophila melanogaster ; genetics ; olfactory response ; strain difference
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract A simple olfactometer was constructed for measuring the responses of adultDrosophila to odoriferous substances, and an index (attractability index, AI) is proposed to evaluate the response. Five strains ofDrosophila melanogaster of different geographic origins were tested for their responses to five chemical attractants: ethyl alcohol, acetic acid, lactic acid, ethyl acetate, andn-butyraldehyde. Statistical analysis has shown that the differences of AI among strains are highly significant for all the odorants except acetic acid and that male flies are, in general, less sensitive than females. The number of flies which were inactive in the olfactometer also varied with strain, sex, and odorant, suggesting the involvement of some other behaviors, and this raises some difficulties in interpreting the heterogeneities of AI. Nevertheless, these results suggest that a considerable amount of genetic variation for olfactory response exists in natural population ofD. melanogaster.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 131
    ISSN: 1573-3297
    Schlagwort(e): minority mating advantage ; Drosophila melanogaster ; mating behavior ; male courtship cues ; habituation by female
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (10∶10 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority ratio (2∶18). In direct observation of single females with equal numbers of males (3∶3) as controls,O males courted less and more slowly thanR males, but females mated with either type without bias. When unequal (4∶1), the minority males were successful at more than twice the frequency expected. Whether successful or not, the minority males did not change their level of courtship, and thus cannot be said to compensate for their frequency in any way. The time between first courtship and mating was less for the minority males than for the majority males. We discard the hypothesis that the minority male will be accepted immediately or ahead of a majority male, because the opposite tended to occur: that if a minority male courted first he was less likely to be successful than if he waited until the majority courted. Our results then are in conformity with the hypothesis that a female samples males and their courtship cues, thus becoming habituated to the majority of the first courting male, but she accepts a male with a cue different from that which she originally detected but avoided. That male is most often the minority.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 132
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 8 (1978), S. 399-414 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; olfactory response ; genetics ; chemical odorants ; odor-specific variant
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Homozygous second chromosome lines were extracted from a natural population ofDrosophila melanogaster and tested for their olfactory responses to ethyl acetate. The chromosome lines were highly heterogeneous for this behavior, and the variability was also specific to other esters and ketones such as ethyl propionate, 2-butanone, 2-pentanone, and 3-pentanone. The responses to these odorants negatively correlated with the response to another odorant, lactic acid. A large part of this odorant-specific variation seemed to be controlled by genes located on the right arm of the second chromosome.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 133
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 8 (1978), S. 475-479 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; selective breeding ; digging ; pupation site
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The genetics of the digging behavior ofDrosophila melanogaster larvae was studied through selective breeding. Selection for low digging activity was successful, but selection for high digging activity was not. Selection for low and high digging activity affected another behavior, namely the choice of a pupation site. Digging behavior appears to be under polygenic control.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 134
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 8 (1978), S. 487-502 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; ebony mutant ; black mutant ; β-alanine ; mating behavior ; aggression ; phenocopy ; dark strains ; light strains ; territorialism ; arena behavior ; spatial isolation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Effects of β-alanine on mating behavior and aggression were studied inDrosophila melanogaster using the following competitive pairs: (1) homozygous black (b/b) flies, in which β-alanine synthesis is decreased, vs. alanine is blocked vs. wild-type (e +/e+) flies; (2) dark flies, in which β-alanine incorporation is reduced, owing mainly to chromosome 3, vs. light flies collected from the same population as were the dark flies; (3) homozygous black (b/b) flies, in which β-alanine synthesis is decreased, vs. β-alanine-injectedb/b flies, which are phenocopies of wild-type flies. The behavior of mixed-sex groups was studied in a large, illumination-graded observation chamber containing food and in small uniformly illuminated cells also containing food. The relative competitive mating abilities of these types were measured in both experimental conditions. Uninjected black flies, but not injected ones, showed weak and unsteady gait and weak wing extension. In ebony these abnormalities were more extreme. Dark flies did not show these abnormalities. Accelerated sexual maturation was indicated in males by early onset of courtship and enhanced territorial aggression and in females by earliness of mating. Such acceleration was observed in ebony and dark flies, compared with light flies, and among β-alanine-injectedb/b flies competing with uninjected black flies. Ebony males, although maturing earlier than wild-type males, were less successful than wild-type males in mating. This difference was even greater when the flies were all allowed to mature before competing. Ebony females outmated wild-type females. Dark flies outmated light flies, and β-alanine-injectedb/b males outmated uninjected black males, especially in bright light. Ebony flies mated much longer than wild-type flies, and black flies mated slightly longer than injectedb/b flies. There was some spatial isolation of ebony from wild type, dark from light, and β-alanine-injected from uninjectedb/b flies in the illumination-graded observation chamber. Ebony flies more than wild type concentrated near food. Flies were attracted to the current of moist inlet air. They were also attracted to deposited excrement, and males defended such deposits as a mating area, thus showing rudiments of arena behavior in which a mating area away from the oviposition site is defended. Usually, however, the defended area focused on food.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 135
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 5 (1975), S. 9-16 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; temperature ; spatial distribution ; geotaxis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The effect of temperature and sex on spatial distribution ofDrosophila melanogaster adults was studied in a specially designed apparatus. It was observed that individuals tend to aggregate in sections of the sphere independently of sex and temperature. Nevertheless, decrease in temperature increase aggregation. The mobility of both males and females indicates a megative geotactic tendency.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 136
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 5 (1975), S. 17-25 
    ISSN: 1573-3297
    Schlagwort(e): phototaxis ; Drosophila melanogaster ; Drosophila simulans ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The phototactic responses of four recently collected isofemale strains ofDrosophila melanogaster andDrosophila simulans were measured in a light gradient from 590 to 10 lux. High light intensities were preferred by most flies, but a small proportion of flies preferred the lowest light intensity. Based on the strains tested,D. simulans showed greater phototaxis thanD. melanogaster, and within each species variability was found. The niche breadth ofD. melanogaster appears likely to be greater than that ofD. simulans for phototaxis in the light gradient. These results are in general qualitative agreement with earlier results published on dispersal activities from the same populations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 137
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 7 (1977), S. 251-259 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; courtship song ; mutagenesis ; fate mapping
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract A mutant Drosophila melanogaster with an aberrant courtship song has been isolated. The interval between pulses and the length of the pulses are increased. The pulses are polycyclic rather than monocyclic. Flight wingbeat and sine song frequency remain unchanged. The mutation is mapped and fate-mapped. The results from the latter investigation are inconclusive.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 138
    Digitale Medien
    Digitale Medien
    Springer
    Behavior genetics 7 (1977), S. 433-439 
    ISSN: 1573-3297
    Schlagwort(e): Drosophila melanogaster ; larvae ; digging behavior
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract The digging behavior of larvae from the following strains ofDrosophila melanogaster was studied: Oregon R-c, taxi, yellow, and vestigial. It was found that the time of stay of preadults in the culture medium, the number of larvae, and the illumination conditions can modify this behavior. The presence of this characteristic depends on the genetic composition of the population: the larvae of each strain used exhibited their own particular pattern of dispersal throughout the culture medium, independent of the experimental conditions under which this behavior was surveyed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...