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Organisms are exposed to various stresses caused by environmental fluctuations. One of the most common stresses is the shortage of food. Individuals of many species must survive periods of starvation. There appears to be a trade‐off between reproduction and survival. When residual reproductive value declines for an individual, life‐history theory predicts an increase in current reproductive investment. Current reproductive investment differs between virgin and mated individuals. It is likely that mating experience influences starvation tolerance. However, few studies have investigated sex differences in the effect of mating experience on starvation tolerance or clarified the causes of reductions in starvation tolerance in both sexes. In the present study, these questions are investigated using the seed bug Togo hemipterus (Heteroptera: Lygaeidae).The results of the present study demonstrate that mating is costly for both sexes. Mated males show very short survival times and a daily reduction in weight, and daily energy expenditures are significantly greater in mated males than in virgin males. It is possible that starvation increases the mating effort of males, such as behavioural activities and the amount of time spent searching for females. A trade‐off between survival duration and lifetime fecundity is found in virgin females. However, there is no trade‐off in mated females, which have very short survival times. Whether male seminal substances contribute to the short survival times of mated females is considered. This is the first report demonstrating the influence of sex and mating experience on starvation tolerance. Sex‐specific causes for reductions in starvation tolerance are discussed.  相似文献   
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Protected areas constitute strategy for biodiversity conservation. Unfortunately, these sanctuaries of biodiversity are submitted to a high human pressure in Togo. This study carried out in the Alédjo protected area, aimed to make an analysis of various forms of human footprints and their impact on its plant resources. Methodological approach was based on forest inventory completed by inquiries. Ninety‐four wooded species belonging to 35 families were counted. Floristic data analysis showed that seven species: Isoberlinia doka Craib & Stapf, Daniellia oliveri (Rolfe) Hutch. & Dalz., Berlinia grandiflora (Vahl) Hutch. & Dalz., Pterocarpus erinaceus Poir., Zanha golungensis Hiern, Khaya senegalensis (Desv.) A. Juss., Pentadesma butyracea Sabine was prominent. Five vegetation types were identified: riparian forests, dry forests, open forests, savanna woodlands, tree/shrub savannas with variable structural characteristics. The diversity indices in these plant communities are well significant and indicate a good distribution of species in the area. Several human activities such as fuel wood, fruits and medicinal plants gathering, carbonization, pasture were found within the protected area. Local authorities and associations are involved in the management of the protected area, but the participation of local populations needs to be improved.  相似文献   
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Leaping African mullet Mugil capurrii was caught along the Togolese coast in the Gulf of Guinea. This is the first record of this species which usually occurs from Morocco to Guinea Bissau and the southernmost point of its known distribution.  相似文献   
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Fonio millet (Digitaria exilis Stapf, Digitaria iburua Stapf) is known in Togo far several centuries and has played a strategic role in the household food security mainly in rural areas. Using Participatory Research Appraisal (PRA) tools and techniques, 55 villages randomly selected in the two production zones of Togo were surveyed to document the ethnobotanical and indigenous knowledge related to its production, diversity, use and conservation. For all of the ethnic groups involved in fonio production in Togo (Akposso and Akébou in the south; Losso-Nawda, Lamba, Tamberma, Tchokossi and Gangan in the north), the crop has a high sociocultural value. The fonio genetic diversity being managed by the farmers seems important as 42 landraces were recorded. Two lines of origin that contributed to this current genetic diversity (local domestication or introduction from neighbouring countries) were reported by the farmers. Cooking qualities, growth cycle, colour and size of the grains are the main criteria used by farmers to describe varieties. According to farmers, fonio production and diversity are being regressing because of several constraints of which the most important are lack of adequate harvest, threshing and processing technologies and development of pests and diseases. The important ethnobotanical and indigenous data recorded will be useful in accessing the genetic diversity of the crop in Togo and in defining appropriate strategies for its conservation on farm.  相似文献   
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The Beffa form of Simulium soubrense Vajime & Dunbar, a member of the S. sanctipauli sub-complex of the S. damnosum complex, was found breeding throughout rivers in the Togo-Benin Gap, as far north as 9 degrees 30'N. Its distribution changed with the season. In southern Togo there were seasonal fluctuations in the relative abundancies of the Beffa form and of S. damnosum/S.sirbanum. There was considerable temporal and regional variation in the frequencies of different colour morphs of adult flies. The flies in Benin tended to be darker. Infections with Onchocerca volvulus (Leuckart) appeared to be independent of the host's colour morph category. Larger flies harboured significantly more first stage Onchocerca larvae but no significant relations with fly size were found for second and third stage larvae.  相似文献   
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Abstract. Males of the Beffa form of Simulium soubrense Vajime and Dunbar were successfully crossed with female S.squamosum V. & D. and S.sanctipauli V. & D. Fertile eggs from both crosses were reared to larvae and, in the case of the BeifaXsquamosum cross, to adults.
Larval chromosomes from the Beffa x sanctipauli cross had normally paired homologues but those of the Beffa xsquamosum cross showed extensive asynapsis and large heterozygous loops. The morphology of the larval and adult hybrids from the BeftaXsquamosum cross were more characteristic of squamosum , but the adult males had scutal patterns typical of the Beffa form and retained this form's laboratory-mating propensity.  相似文献   
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