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LINA SANDRIN JOËL MEUNIER SHIRLEY RAVEH JEAN‐CLAUDE WALSER MATHIAS KÖLLIKER 《Ecological Entomology》2015,40(2):159-166
1. The patterns of multiple paternity among the progeny of females are key properties of genetic mating systems. Female multiple mating should evolve due to direct or indirect benefits, but it may also partly be driven by the encounter rate with different potential mates. 2. In this study this hypothesis was experimentally tested in the European earwig (Forficula auricularia L.) by establishing experimental mating groups that differed in the number of males and females (i.e. density). The number of sires and mean sibling relatedness in each clutch were estimated using microsatellite‐based paternity analysis. 3. As predicted, the mean number of sires per clutch was significantly increased, and sibling relatedness decreased, in the higher density treatment where more potential male mates were available. This change was less than proportional to the number of males in the mating groups, indicating that mechanisms limiting multiple paternity in large mating groups were involved. There were no significant relationships between female reproductive success or male siring success with morphology (body size, weight, and forceps size). 4. The present results show that multiple paternity in F. auricularia clutches is partly determined by the availability of male mates and suggest that this effect is modulated by mechanisms in males and/or females that limit multiple paternity. 相似文献
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LUCAS GONTIJO MARCOS C. VIEIRA WALTER S. DE ARAÚJO MÁRIO ALMEIDA‐NETO 《Ecological Entomology》2014,39(6):716-722
1. All else being equal, the greater the local species richness of plants, the greater the number of associated herbivore species. Because most herbivore insects feed on a subset of closely related plant species, plant phylogenetic diversity is expected to play a key role in determining the number of herbivore species. What is not well known, however, is how an increase in the species richness of exotic plants affects the species richness of herbivores. 2. In this study, we used plant–fruit fly interactions to investigate the influence of the proportion and species richness of exotic host plants on the species richness of herbivorous insects. We also tested whether the phylogenetic diversity of host plants increases when the number of exotic plant species increases. 3. We found that the species richness of fruit flies is more accurately predicted by the richness of native host plants than by total plant species richness (including both native and exotic species). The proportion of exotic host species and the phylogenetic diversity of host plants had negative and positive effects, respectively, on the species richness of fruit flies. 4. Our findings suggest that a positive effect of plant richness on herbivore richness occurs only when an increase in plant diversity involves plant species with which native herbivores share some evolutionary history. 相似文献
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Virgin and recently mated males are equally able to achieve new matings in Neoleucinodes elegantalis
WENDEL J. TELES PONTES ERIVELTON G. CUNHA HERNANE D. ARAÚJO REGINALDO BARROS ERALDO LIMA 《Physiological Entomology》2013,38(4):313-317
Lepidopteran male mating success is recognized to be directly related to physical and behavioural traits such as ability, vigour, activity and persistence in courtship. In the tomato fruit borer Neoleucinodes elegantalis Guenée, the mating system is known to be monogamic and therefore males' sexual investment is apparently low. The hypothesis that recently mated males have a remating probability equal to that of virgin males is tested. The impact of body size in remating success and the cost of remating are also analyzed. Mated males show as much propensity to remate as naïve ones. Copula duration and the time taken to copulate are similar in mated and virgin males. However, spermatophore size is not related to male size. The results suggest the ability of N. elegantalis males to remate within 24 h between mating events and their propensity to remate are not affected by copula investment. © 2013 The Royal Entomological Society 相似文献
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Hybrid speciation in sparrows I: phenotypic intermediacy,genetic admixture and barriers to gene flow
JO S. HERMANSEN STEIN A. SÆTHER TORE O. ELGVIN THOMAS BORGE ELIN HJELLE GLENN‐PETER SÆTRE 《Molecular ecology》2011,20(18):3812-3822
Homoploid hybrid speciation is thought to require unusual circumstances to yield reproductive isolation from the parental species, and few examples are known from nature. Here, we present genetic evidence for this mode of speciation in birds. Using Bayesian assignment analyses of 751 individuals genotyped for 14 unlinked, nuclear microsatellite loci, we show that the phenotypically intermediate Italian sparrow (Passer italiae) does not form a cluster of its own, but instead exhibits clear admixture (over its entire breeding range) between its putative parental species, the house sparrow (P. domesticus) and the Spanish sparrow (P. hispaniolensis). Further, the Italian sparrow possesses mitochondrial (mt) DNA haplotypes identical to both putative parental species (although mostly of house sparrow type), indicating a recent hybrid origin. Today, the Italian sparrow has a largely allopatric distribution on the Italian peninsula and some Mediterranean islands separated from its suggested parental species by the Alps and the Mediterranean Sea, but co‐occurs with the Spanish sparrow on the Gargano peninsula in southeast Italy. No evidence of interbreeding was found in this sympatric population. However, the Italian sparrow hybridizes with the house sparrow in a sparsely populated contact zone in the Alps. Yet, the contact zone is characterized by steep clines in species‐specific male plumage traits, suggesting that partial reproductive isolation may also have developed between these two taxa. Thus, geographic and reproductive barriers restrict gene flow into the nascent hybrid species. We propose that an origin of hybrid species where the hybrid lineage gets geographically isolated from its parental species, as seems to have happened in this system, might be more common in nature than previously assumed. 相似文献
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GEOFFREY M. REED JOÃO MENDONÇA CORREIA PATRICIA ESPARZA SHEKHAR SAXENA MARIO MAJ 《World psychiatry》2011,10(2):118-131
This article describes the results of the WPA-WHO Global Survey of 4,887
psychiatrists in 44 countries regarding their use of diagnostic classification
systems in clinical practice, and the desirable characteristics of a classification
of mental disorders. The WHO will use these results to improve the clinical
utility of the ICD classification of mental disorders through the current
ICD-10 revision process. Participants indicated that the most important purposes
of a classification are to facilitate communication among clinicians and to
inform treatment and management. They overwhelmingly preferred a simpler system
with 100 or fewer categories, and over two-thirds preferred flexible guidance
to a strict criteria-based approach. Opinions were divided about how to incorporate
severity and functional status, while most respondents were receptive to a
system that incorporates a dimensional component. Significant minorities of
psychiatrists in Latin America and Asia reported problems with the cross-cultural
applicability of existing classifications. Overall, ratings of ease of use
and goodness of fit for specific ICD-10 categories were fairly high, but several
categories were described as having poor utility in clinical practice. This
represents an important focus for the ICD revision, as does ensuring that
the ICD-11 classification of mental disorders is acceptable to psychiatrists
throughout the world. 相似文献
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Yong Hun JO Seung Han OH Bo Mi PARK Dong Hyun Kim Bharat Bhusan PATNAIK Ho Beom LEE Hun Cheon JEONG Yong Seok LEE Kisung KO In Seok Bang Iksoo KIM Yeon Soo HAN 《Entomological Research》2011,41(6):293-293
The tumor suppressor, QM, has been cloned and characterized from various model organisms such as human, plant and invertebrates. Yet, it has not been seriously investigated for its role in conjunction with antiviral mechanisms involving innate insect immunity. From the expressed sequence tag (ESTs) project, conducted with larval cDNA library of cabbage butterfly, Pieris rapae, a partial fragment (718 bp) of QM homologue, termed PrQM containing 660 bp long open reading frame (ORF) encoding protein of 219 amino acids was identified. In silico analysis of PrQM ORF revealed the presence of ribosomal protein L10a/L10e type domain. Phylogenetic analysis of the P. rapae QM‐like protein showed high amino acid sequence similarity with other PrQM polypeptides identified from Heliothis virescenes (95%), Plutella rapae (92%), Bombyx mori (92%), Drosophila melanogaster (89%), and Polyrhachis vicina (85%). The butterfly QM has the closest phylogenetic relationship to a moth (Hv) QM homologue. Further investigations revealed the expression of PrQM at all developmental stages, with pronounced presence at the egg stage. In addition, spatial pattern analysis indicated its high expression in the head, salivary gland, integument and fat body with visible presence in Malpighian tubule and gut. Time course expression studies conducted after immune‐challenge with lipoteichoic acid (LTA) showed the induction of PrQM mRNA at 12 h and 24 h after challenge and also in response to granulovirus (GV). Results of this investigation therefore suggest possible role of QM‐like proteins from Pieris rapae to be involved in innate antiviral immune responses. Further elucidation on the precise function of PrQM during antiviral immune responses by using RNA interference remains a viable research front. 相似文献
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JENNIFER DUMONT DAVID COHEN JOËLLE GÉRARD YVES JOLIVET PIERRE DIZENGREMEL DIDIER LE THIEC 《Plant, cell & environment》2014,37(9):2064-2076
Ozone induces stomatal sluggishness, which impacts photosynthesis and transpiration. Stomatal responses to variation of environmental parameters are slowed and reduced by ozone and may be linked to difference of ozone sensitivity. Here we determine the ozone effects on stomatal conductance of each leaf surface. Potential causes of this sluggish movement, such as ultrastructural or ionic fluxes modification, were studied independently on both leaf surfaces of three Euramerican poplar genotypes differing in ozone sensitivity and in stomatal behaviour. The element contents in guard cells were linked to the gene expression of ion channels and transporters involved in stomatal movements, directly in microdissected stomata. In response to ozone, we found a decrease in the stomatal conductance of the leaf adaxial surface correlated with high calcium content in guard cells compared with a slight decrease on the abaxial surface. No ultrastructural modifications of stomata were shown except an increase in the number of mitochondria. The expression of vacuolar H+/Ca2+‐antiports (CAX1 and CAX3 homologs), β‐carbonic anhydrases (βCA1 and βCA4) and proton H+‐ATPase (AHA11) genes was strongly decreased under ozone treatment. The sensitive genotype characterized by constitutive slow stomatal response was also characterized by constitutive low expression of genes encoding vacuolar H+/Ca2+‐antiports. 相似文献
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