246 research outputs found
Insects - a mistake in God's creation? Tharu farmers' perception and knowledge of insects: A case study of Gobardiha Village Development Committee, Dang-Deukhuri, Nepal
Recent trends in agriculturalresearch and development emphasize the need forfarmer participation. Participation not onlymeans farmers' physical presence but also theuse of their knowledge and expertise.Understanding potentials and drawbacks of theirlocal knowledge system is a prerequisite forconstructive collaboration between farmers,scientists, and extension services.An ethnoentomological study, conducted in aTharu village in Nepal, documents farmers'qualitative and quantitative knowledge as wellas perceptions of insects and pest management,insect nomenclature and classification, andissues related to insect recognition and localbeliefs. The study offers a basis to improvepest management programs in terms of efficacyand acceptance. It demonstrates, for instance,that a concept of pests and beneficials isvirtually missing in traditional farmingcommunities and that the Tharu folkclassification profoundly differs from thescientific classification, but is not radicallydifferent from other folk entomologicalsystems. Insects belong to the taxa calledkiraa consisting of arthropods andnon-arthropods that interact with humans. Theyare classified in several overlappinghierarchies where locomotion and human impactplay major roles while morphological criteriaare almost irrelevant. Recognition ofkiraa, however, is dominated by agriculturalaspects followed by physiological-behavioral,ecological, and human-directed features.Morphological criteria play a minor role. Innomenclature, however, the insects' physicalappearance is more important than otherfeatures. The study further shows that male andfemale farmers have different perceptions ofkiraa.The insect-related knowledge system of theTharu has prevented farmers from using modernpesticides in the past. In the course ofmodernization, however, some aspects of theirknowledge system could become obsolete andprove disadvantageous to their livelihood andagro-ecosystem
Correlates of rarity in UK bumblebee (Bombus spp.) populations
The decline of bumblebee (Bombus spp.) populations in the UK and worldwide
has been well reported. It has been generally assumed that such declines result in
the genetic impoverishment of some species, potentially leading to reduced fitness
and increased extinction risk. This study tested the fundamental assumption
linking population fragmentation with fitness, in a model system of two Bombus
species native to the UK. Bombus monticola has declined significantly in range across the UK in recent years and occupies fragmented upland areas, while Bombus pratorum has remained abundant and widespread over many habitat types. The effects of genetic diversity on fitness have been addressed in wild Bombus species,
but this is the first study to explicitly compare data from species of differing
levels of population connectivity and hence test the assumptions of traditional
population genetic theory.
As genetic diversity has often been linked with immunocompetence, aspects of the
innate immune response were quantified, together with parasite load. These empirical measures of fitness showed lower than expected variability between the two study species, and no evidence was found to support the theory of lower fitness
in fragmented populations. However, the considerable variability between sample sites in both species for all parameters measured raised interesting questions
as to the underlying evolutionary processes; it is postulated that B. monticola
populations may maintain a higher than expected Ne, despite their fragmented
distribution. This study also provided methodological developments. An alternative method for the quantification of wing wear as a proxy for age was proposed,
which could be easily applied to other Bombus species and possibly adapted for
use in other flying insects. In addition possible sources of error in AFLP analysis were highlighted which have not been adequately discussed in the current
literature, namely the effects of sample storage. Given the utility of AFLPs for
non-model species, this is an important avenue for future research, and would be
applicable to studies in other systems.
Overall, the data presented here emphasise the challenges of studying fitness in
wild populations, and underline the requirement for research into the fundamental
principles underlying many assumptions made by conservation genetic theory.NER
The assessment report of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services on pollinators, pollination and food production
The thematic assessment of pollinators, pollination and food production carried out under the auspices of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services aims to assess animal pollination as a regulating ecosystem service underpinning food production in the context of its contribution to nature’s gifts to people and supporting a good quality of life. To achieve this, it focuses on the role of native and managed pollinators, the status and trends of pollinators and pollinator-plant networks
and pollination, drivers of change, impacts on human well-being, food production in response to pollination declines and deficits and the effectiveness of responses
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