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31.
The noctuid stem borer Busseola fusca occurs throughout sub‐Saharan Africa, where it is considered as a major pest of corn and sorghum. To understand B. fusca phylogeography, we isolated and characterized eight microsatellite loci in this species. We investigated these loci for polymorphism on a subset sample of individuals from different geographic populations. All loci were polymorphic, showing between four and 10 alleles. Cross‐species amplification of four of these loci was tested on 11 other noctuid species. 相似文献
32.
FLORENCE NOEL MARIE‐CATHERINE BOISSELIER‐DUBAYLE JOSIE LAMBOURDIERE NATHALIE MACHON JACQUES MORET SARAH SAMADI 《Molecular ecology resources》2005,5(4):827-829
Ranunculus nodiflorus and Ranunculus flammula are two closely related Ranunculaceae. In France, the first one is rare and endangered, whereas the second is common. To compare their population genetic structure, seven polymorphic microsatellite markers were characterized. We found no polymorphism in R. nodiflorus, whereas R. flammula was polymorphic at each locus. The total number of alleles per locus varied from three to eight. Observed heterozygosities ranged from 0 to 0.261. This set of microsatellites offers an efficient tool to study population genetic structure and to compare the results between closely related endangered and common species. 相似文献
33.
The response of fawn survival to changes in habitat quality varies according to cohort quality and spatial scale 总被引:3,自引:0,他引:3
34.
A pooled DNA method was used to produce fully informative EST (expressed sequence tag)‐derived markers for the Picea genus. Nine markers were produced from 10 cDNA identified as candidates for cold tolerance or embryogenesis. Indels and SNPs (single nucleotide polymorphisms) were characterized from sequences obtained from pools of 10 individuals for each of the three species: Picea glauca (white spruce), Picea mariana (black spruce) and Picea abies (Norway spruce). Indels were present in 28% of the sequences and SNPs with a frequency greater than 10% were present on average in 1.2% of the positions. 相似文献
35.
NATHALIE S. NAGALINGUM MICHAEL D. NOWAK KATHLEEN M. PRYER 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(4):673-685
Heterosporous ferns (Salviniales) are a group of approximately 70 species that produce two types of spores (megaspores and microspores). Earlier broad‐scale phylogenetic studies on the order typically focused on one or, at most, two species per genus. In contrast, our study samples numerous species for each genus, wherever possible, accounting for almost half of the species diversity of the order. Our analyses resolve Marsileaceae, Salviniaceae and all of the component genera as monophyletic. Salviniaceae incorporate Salvinia and Azolla; in Marsileaceae, Marsilea is sister to the clade of Regnellidium and Pilularia– this latter clade is consistently resolved, but not always strongly supported. Our individual species‐level investigations for Pilularia and Salvinia, together with previously published studies on Marsilea and Azolla (Regnellidium is monotypic), provide phylogenies within all genera of heterosporous ferns. The Pilularia phylogeny reveals two groups: Group I includes the European taxa P. globulifera and P. minuta; Group II consists of P. americana, P. novae‐hollandiae and P. novae‐zelandiae from North America, Australia and New Zealand, respectively, and are morphologically difficult to distinguish. Based on their identical molecular sequences and morphology, we regard P. novae‐hollandiae and P. novae‐zelandiae to be conspecific; the name P. novae‐hollandiae has nomenclatural priority. The status of P. americana requires further investigation as it consists of two geographically and genetically distinct North American groups and also shows a high degree of sequence similarity to P. novae‐hollandiae. Salvinia also comprises biogeographically distinct units – a Eurasian group (S. natans and S. cucullata) and an American clade that includes the noxious weed S. molesta, as well as S. oblongifolia and S. minima. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 673–685. 相似文献
36.
JOSEPH A. TOBIAS NATHALIE SEDDON CLAIRE N. SPOTTISWOODE JOHN D. PILGRIM LINCOLN D. C. FISHPOOL NIGEL J. COLLAR 《Ibis》2010,152(4):724-746
Species are the fundamental units of biology, ecology and conservation, and progress in these fields is therefore hampered by widespread taxonomic bias and uncertainty. Numerous operational techniques based on molecular or phenotypic data have been designed to overcome this problem, yet existing procedures remain subjective or inconsistent, particularly when applying the biological species concept. We address this issue by developing quantitative methods for a classic technique in systematic zoology, namely the use of divergence between undisputed sympatric species as a yardstick for assessing the taxonomic status of allopatric forms. We calculated mean levels of differentiation in multiple phenotypic characters – including biometrics, plumage and voice – for 58 sympatric or parapatric species‐pairs from 29 avian families. We then used estimates of mean divergence to develop criteria for species delimitation based on data‐driven thresholds. Preliminary tests show that these criteria result in relatively few changes to avian taxonomy in Europe, yet are capable of extensive reassignment of species limits in poorly known tropical regions. While we recognize that species limits are in many cases inherently arbitrary, we argue that our system can be applied to the global avifauna to deliver taxonomic decisions with a high level of objectivity, consistency and transparency. 相似文献
37.
ANDREA SUNDERMANN CLAUDIA ANTONS NATHALIE CRON ARMIN W. LORENZ DANIEL HERING PETER HAASE 《Freshwater Biology》2011,56(8):1689-1702
1. River restoration has received considerable attention, with much recent focus on restoring river hydromorphology to improve impoverished aquatic communities. However, we still lack a clear understanding of the response of aquatic biota to river restoration. 2. We studied the effects of hydromorphological restoration on benthic invertebrate assemblages in 25 river sites in Germany using standardised methods. Restoration efforts were primarily aimed to restore habitat heterogeneity; correspondingly, habitat diversity increased at most sites. 3. Similarity of benthic invertebrate assemblages between restored and unrestored river sections was low (mean similarity was 0.32 for Jaccard and 0.46 for Sørensen). Community‐based metrics, such as the percentage of Ephemeroptera, Plecoptera and Trichoptera taxa, also differed between restored and unrestored sections. 4. Only three of the 25 restored sections were classified as having ‘good ecological quality’ class according to the European Water Framework Directive criteria; hence, poor water quality is probably one factor impeding recolonisation. 5. Our results show that isolated restoration measures do not necessarily result in positive effects on aquatic biota and that better understanding of the interconnectedness within a catchment is required before we can adequately predict biotic responses to structural river restoration. 相似文献
38.
YANNICK R. Delettre NATHALIE Morvan PAUL Tre´HEN PATRICK Grootaert 《Biodiversity and Conservation》1997,7(1):9-25
The empidid fauna of four small adjacent biotopes bordering a pond was investigated for 2 consecutive years in Brittany (France). Adult activity was studied using yellow water traps, whereas suitable larval habitats were determined using emergence traps. While 24 species emerged from the soils, 45 flew above the four sites. The number of species emerging from each site was nearly identical. However, the highest number of individuals emerged from the heathland and numbers rapidly declined towards the pond banks. On the contrary, the greatest aerial activity occurred in the woodlot and near the pond banks. Fourteen times less flying activity was found above the dry heathland. The latter appeared to be a site of larval growth but mating and feeding of the adults took place in the woodlot. Reproduction sites and space used by the adults differed among the dominant species. The species assemblage could not be fully explained within the spatial limits of the four sites. Considering the species'behaviour, it is suggested that immigration of species and individuals from other sites should explain these differences. The study, which is supported by four other research works, emphasizes the role of key resource played by ecotonal zones between aquatic and terrestrial ecosystems in the persistence of species over a larger set of habitats. Considering the complementarity of habitats is essential to explain diversity patterns in species which need different space units to complete their life-cycle. 相似文献
39.
LAËTITIA MONTES NATHALIE LE ROY MARTINE PERRET VIVIAN DE BUFFRENIL JACQUES CASTANET JORGE CUBO 《Biological journal of the Linnean Society. Linnean Society of London》2007,92(1):63-76
We explored the factors that explain the variation in resting metabolic rates (RMR) in growing amniotes by using the phylogenetic comparative method. For this, we measured raw RMR (mL O2 h−1 ), body mass, body mass growth rate, and periosteal bone growth rate in a sample of 44 growing individuals belonging to 13 species of amniotes. We performed variation partitioning analyses, which showed that phylogeny explains a significant fraction of the variation of mass-specific RMR (mL O2 h−1 g−1 ), and that the cost of growth is much higher than the cost of maintenance. Moreover, we tested the hypothesis of the independence of energy allocation, and found that maintenance metabolism and growth rates are not significantly related. Finally, we calculated the statistical parameters of the relationship between geometry-corrected RMR (mL O2 h−1 g−0.67 ) and bone growth rate. This relationship could potentially be used in palaeobiology to infer RMR from bone tissue samples of fossil species by assuming Amprino's rule (according to which bone tissue types reflect bone growth rates). These estimates would be especially interesting for Mesozoic non-avian theropod dinosaurs and Permian and Triassic therapsids to investigate, respectively, the origin of avian and mammalian endothermy. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 63–76. 相似文献
40.
ANDALO CHRISTOPHE; RAQUIN CHRISTIAN; MACHON NATHALIE; GODELLE BERNARD; MOUSSEAU MARIANNE 《Annals of botany》1998,81(3):405-411
Individuals ofArabidopsis thaliana, collected in different naturalpopulations, were grown in controlled and elevated CO2in a glasshouse.Following germination, root growth of progeny of different linesof these populations was studied in control and elevated atmosphericCO2. No significant direct effect of atmospheric CO2concentrationcould be demonstrated on root growth. An important parentaleffect was apparent, namely that root length and branching weredecreased in seeds collected from a mother plant which had beengrown in elevated CO2. This was correlated with smaller seeds,containing less nitrogen. These parental effects were geneticallyvariable. We conclude that CO2may affect plant fitness via parentaleffects on seed size and early root growth and that the geneticvariability shown in our study demonstrates thatArabidopsispopulationswill evolve in the face of this new selective pressure.Copyright1998 Annals of Botany Company Root growth, root branching, seed, elevated CO2, natural population,Arabidopsis thaliana, parental effect. 相似文献