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901.
Systematics and origin of moths in the subfamily Arctiinae (Lepidoptera,Erebidae) in the Neotropical region
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Mauricio M. Zenker Niklas Wahlberg Gunnar Brehm José A. Teston Lukasz Przybylowicz Marcio R. Pie André V.L. Freitas 《Zoologica scripta》2017,46(3):348-362
The availability of standard protocols to obtain DNA sequences has allowed the inference of phylogenetic Hypotheses for many taxa, including moths. We here have inferred a phylogeny using maximum‐Likelihood and Bayesian approaches for a species‐rich group of moths (Erebidae, Arctiinae), with strong emphasis on Neotropical genera collected in different field campaigns in the Atlantic Forest of Brazil, eastern Amazon and southern Ecuador. A total of 277 species belonging to 246 genera were included in the analysis. Our main objectives were to shed light on the relationships between suprageneric groups, especially subtribes, and hypothesize colonization events in and out of the Neotropics. The monophyly of Arctiinae and its four tribes (Lithosiini, Amerilini, Syntomini and Arctiini) was recovered in the ML and Bayesian trees. Three Lithosiini subtribes previously found and two additional species groups were recovered monophyletic in both phylogenetic estimation methods. In Arctiini, the monophyly of Spilosomina and Arctiina was highly supported in the ML and Bayesian trees, but the monophyly of Ctenuchina and Echromiina was weakly supported in the ML tree and absent in the Bayesian tree; the remaining subtribes were paraphyletic and, in the case of Phageopterina, formed several species groups. The mapping of species occurrence in our ML tree suggests that Arctiinae have an Old World origin and that the Neotropical region was colonized at least six times independently. Our analysis also suggests that a number of species that occur in Neotropical and other zoogeographic regions may have originated in the Neotropics, although further taxon sampling is required to support this hypothesis. To our knowledge, this is the first time that a highly speciose group of tropical moths is well covered in a phylogeny, and it seems plausible that the results reported here may be extendable to other species‐rich tropical undersampled moth taxa. 相似文献
902.
Gene frequency distributions observed in large-scale surveys of species of Drosophila are shown to be incompatible with a genetic model involving neutral mutations and genetic drift alone. The data are, however, qualitatively similar to predictions based on an alternative model of natural selection for an optimal level of enzyme activity in addition to drift and mutation. The intensity of selection detected reduces the mean rate of gene substitution to less than one-quarter that expected on the neutral-allele hypothesis. 相似文献
903.
A minichromosome has originated from the transposing elementTE1. This autonomously replicating chromosome contains the structural genes white and roughest, from theDrosophila X chromosome. It arose within a stock carryingTE1 at 45F on chromosome2. In addition to thew andrst genes, the minichromosome may carry section 45C–45F from chromosome2. It is inherited by 33%–47% of the offspring. By this criterion it carries a centromere, although the origin of the centromere is unknown. From this minichromosome a still smaller one has originated, probably through the loss of all material from chromosome2 together with some heterochromatin. At the same time a duplication of white and roughest could have taken place. This chromosome has a strange morphology and is more frequently lost in meiosis than the larger one, but is still transmitted to about 29%–37% of the progeny of one parent heterozygous for the minichromosome. In both cases the flies have variegated eyes, probably as a result of position-effect variegation. The variegation pattern is influenced by factors in theX chromosome. The size of the smaller minichromosome is little more than 1 Mb as determined by pulsed field gel electrophoresis. 相似文献
904.
Maria Sporbert Petr Keil Gunnar Seidler Helge Bruelheide Ute Jandt Svetlana Aćić Idoia Biurrun Juan Antonio Campos Andraž Čarni Milan Chytrý Renata Ćušterevska Jürgen Dengler Valentin Golub Florian Jansen Anna Kuzemko Jonathan Lenoir Corrado Marcenò Jesper Erenskjold Moeslund Aaron Pérez-Haase Solvita Rūsiņa Urban Šilc Ioannis Tsiripidris Vigdis Vandvik Kiril Vasilev Risto Virtanen Erik Welk 《Journal of Biogeography》2020,47(10):2210-2222
905.
The closely related genera Carestiella, Schizoxylon and Stictis (Stictidaceae, Ostropales, Ascomycota) are revised in northern Scandinavia, and a revised phylogenetic hypothesis, including all seven species of this group in the area, is presented. A key to the species of Stictis s. lat. (including Carestiella, Schizoxylon and Stictis) in Northern Scandinavia is presented. S. albescens and S. confusum are described as new to science, and the new name S. brunnescens is introduced for S. mollis ssp. populorum, when treated as a distinct species. C. socia and S. albescens are the only representatives of their genera in northern Scandinavia, but a total of five species of Stictis are present in the area (S. brunnescens, S. confusum, S. mollis, S. populorum and S. radiata). Substantial within-species variation in ascoma morphology and wall pigmentation is revealed and discussed, and found to correlate with fungal lifestyles; optional lichenization apparently affects several details in fungal anatomy and morphology. 相似文献
906.
Gunnar Hiorth 《Molecular & general genetics : MGG》1942,80(1):289-349
Ohne ZusammenfassungMit 28 Textfiguren 相似文献
907.
Andrew G. Lambertsson S. Bertil Rasmuson Gunnar D. Bloom 《Molecular & general genetics : MGG》1970,108(4):349-357
Summary Ribosomes were isolated from larvae and adult flies, and the purity of the preparation was checked by electron microscopy. The ribosomal proteins were extracted with cold dilute hydrochloric acid, and precipitated with cold acetone. The proteins were characterized by polyacrylamide gel electrophoresis. At pH 3.0 at least 25 bands of different color intensities were resolved, forming a complex pattern.On the basis of electrophoretic mobilities, it was shown that some ribosomal proteins are species-specific, and that larval ribosomes have three protein components more than ribosomes from adult flies.Incubation of the ribosomes with 0.75 M NH4Cl at a low Mg++ concentration lead to detachment of 64% of the ribosomal protein. This detachment of protein molecules was considerably reduced by a five-fold increase of Mg++ ions. 相似文献
908.
Paul Jacobi Christian Ucke Michael Vollmer Thomas Bührke Gunnar Radons Hans Blümer 《当今生物学》1998,28(2):X-XII
909.
910.
Jan C. Axmacher Gunnar Brehm reas Hemp Henry Tünte Herbert V. M. Lyaruu Klaus Müller-Hohenstein Konrad Fiedler 《Journal of Biogeography》2009,36(2):337-349
Aim This study was conducted to investigate the potential of predicting alpha diversity and turnover rates of a highly diverse herbivorous insect family (Geometridae) based on vascular plant species richness and vegetation structure. Location The study was carried out on the south‐western slopes of Mount Kilimanjaro within a wide range of habitats between 1200 and 3150 m elevation. Methods The floristic and structural composition of the vegetation was recorded at 48 plots of 400 m2. Geometrid moths were sampled manually at light sources located at the plot centres. Principal components analysis, redundancy analysis and multiple linear regression were used to explore how alpha diversity and species turnover of geometrid moths are related to vegetation structure and plant species richness. Results Alpha diversity of geometrid moths was significantly correlated with species diversity patterns in the most common vascular plant families (R2 = 0.49) and with plant structural parameters (R2 = 0.22), but not with overall floristic diversity. Species turnover of geometrid moths was strongly linked to diversity changes in a range of plant families (40% explained variance), less strongly to changes in vegetation physiognomy (25%), and only weakly to overall floristic diversity (5%). Changes in elevation were a better predictor of both alpha diversity and species turnover of geometrid moths than any principal component extracted from the vegetation data. Main conclusions Vegetation composition, diversity and structure all showed significant correlations with the diversity and species composition of geometrid moth assemblages. Nevertheless, in most cases relationships were indirect, via environmental parameters such as temperature and humidity, which influenced both vegetation and moth fauna. Possible direct links between geometrid diversity and potential food plants were much weaker. The lack of a significant correlation between overall plant species richness and geometrid diversity indicates that tropical geometrid moths may not be very selective in their food plant choice. Accordingly, a clear correlation between floral diversity and herbivore species richness must be regarded as overly simplistic, and the diversity of vascular plants cannot universally be used as a suitable biodiversity indicator for diverse insect taxa at higher trophic levels. 相似文献