16 research outputs found

    Laubheuschrecken und Grillen (Orthoptera: Ensifera) im Kakamega Forest Reserve, Kenia

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    Das primäre Ziel des BIOTA Ost Teilprojektes E06 (HÄUSER et al. 2003) ist die Erforschung der Tag- und Nachtfalterfauna im Kakamega Forest Reserve, einem Schutzgebiet in Westkenia, ca. 50 km nördlich der am Viktoriasee gelegenen Provinzhauptstadt Kisumu (siehe auch KOKWARO 1988). Während der Feldarbeit wurden außer Lepidopteren auch zahlreiche Orthopteren erfasst, in erster Linie Ensifera und Caelifera. In den National Museums of Kenya (NMK) in Nairobi befindet sich zudem eine umfangreiche Sammlung kenianischer Orthopteren, die während der Aufenthalte in Kenia eingesehen werden konnte. Die vorliegende Arbeit bietet einen vorläufigen Überblick über die Orthopterenfauna des Kakamega Forest Reserve und basiert im Wesentlichen auf diesen genannten Quellen. Es ist uns ein Anliegen, mit diesem knappen Überblick weitere Arbeiten und Studien über diese interessante und ökologisch wichtige Insektengruppe im Untersuchungsgebiet anzuregen.In the BIOTA East Project E06 (BMBF project ID 01LC0025), 3 field trips to the Kakamega Forest Reserve were undertaken between September 2002 and January 2004. Among other Orthoptera representatives 122 specimens of Ensifera were recorded. Most of the specimens were collected manually, using a net, or recorded at light traps. The number of species occurring in Kenya is about 200 according to the National Museums of Kenya (NMK) collection, literature data (KEVAN 1950, KEVAN & KNIPPER 1961, OTTE et al. 1988), and OSF (OTTE & NASKRECKI 1997). According to the Orthoptera Species File, OSF (http://osf2x.orthoptera.org/osf2.2/OSF2X2Frameset.htm) the type locality of 94 species is located in Kenya. Both figures will most probably increase significantly in the future. From the Kakamega Forest region, 33 species in 7 families are reported to date, based on our own field collecting (122 specimens) and NMK data (about 60 specimens). The estimated minimal number of occurring species is 60

    Aspects determining the risk of pesticides to wild bees: risk profiles for focal crops on three continents

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    In order to conduct a proper risk assessment of pesticides to bees, information is needed in three areas: the toxicity of the pesticide;the probability of bee exposure to that pesticide; andthe population dynamics of the bee species in question.Information was collected on such factors affecting pesticide risk to (primarily wild) bees in several crops in Brazil, Kenya and The Netherlands. These data were used to construct ‘risk profiles’ of pesticide use for bees in the studied cropping systems. Data gaps were identified and potential risks of pesticides to bees were compared between the crops. Initially, risk profiling aims to better identify gaps in our present knowledge. In the longer term, the established risk profiles may provide structured inputs into risk assessment models for wild and managed bees, and lead to recommendations for specific risk mitigation measures. Keywords: pesticide, exposure, risk, wild bees, risk profil

    Brazilian cave heritage under siege

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    info:eu-repo/semantics/publishe

    The molecular mechanism of immune evasion by the eggs and larvae of the endoparasitoid Venturia canescens in its host, Ephestia kühniella

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    Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 199

    EAFRINET and the Taxonomic Impediment: perspectives from the developing world

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    Taxonomic capacity in the developing world is seriously lacking, and as such species identification for both pests and useful species is seriously hampered. Some of these species are key indicators of environmental health and climatic changes, and as such call for continuous and informed monitoring. From the developing world point of view, several useful indicators can be listed for lifecycle assessment. However, such would be limited to taxa that have experts and have been researched on and documented in the region. Such indicators as spiders (Araneae), terrestrial molluscs (Mollusca), bees (Apidae) and beetles (Coleoptera) and their value as indicators are discussed. Measurements of environmental damage and resultant loss of biodiversity, both at the species level (micro) and at the landscape level (macro) as a key baseline for decision making in environmental planning and management form part of the taxonomic mandate. One component of the life cycle assessment, beyond the biodiversity and ecosystem health analysis, therefore must address landscape level impacts. From a developing world perspective, this must involve evolving a toolkit for assessing the economic values of biodiversity and land use impact, including human health and food security. Species stockdynamics, such as availability, ranking and user-preferences, and human/scientific perspectives should form a critical part of the assessment, and within the taxonomic networks this is measured by availability and subsequent access to information and data that is useful and relevant in both space and time. Intra-institutional issues that may contribute to this impediments, and which can be transformed into opportunities to supplement and indeed, bulwark the assessment will be addressed in this paper

    Nucleotide Variability at Its Limit? Insights into the Number and Evolutionary Dynamics of the Sex-Determining Specificities of the Honey Bee Apis mellifera

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    Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116-145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene
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