A large‐scale latitudinal pattern of life‐history traits in a strictly univoltine damselfly

1. Variation in thermal conditions and season length along latitudinal gradients affect body size‐related traits over different life stages. Selection is expected to optimise these size traits in response to the costs and benefits. 2. Egg, hatchling, larval and adult size in males and females were estimated along a latitudinal gradient of 2730 km across Europe in the univoltine damselfly Lestes sponsa, using a combination of field‐collection and laboratory‐rearing experiments. In the laboratory, individuals were grown in temperatures and photoperiod simulating those at the latitude of origin, and in common‐garden conditions. 3. The size of adults sampled in nature was negatively correlated with latitude. In all populations the females were larger than the males. Results from simulated and common‐garden rearing experiments supported this pattern of size difference across latitudes and between sexes, suggesting a genetic component for the latitudinal size trend and female‐biased size dimorphism. In contrast, hatchling size showed a positive relationship with latitude, but egg size, although differing between latitudes, showed no such relationship. 4. The results support a converse Bergmann cline, i.e. a negative body size cline towards the north. This negative cline in body size is probably driven by progressively stronger seasonal time and temperature constraints towards the higher latitudes and by the obligate univoltine life cycle of L. sponsa. As egg size showed no relationship with latitude, other environmental factors besides temperature, such as desiccation risk, probably affect this trait.     

Evidence of digenic inheritance in autoinflammation-associated genes

Familial Mediterranean fever (FMF) has traditionally been considered as a monogenic autosomal recessive disorder caused by mutations in the MEFV gene with highest incidence among Mediterranean populations. In a considerable number of patients with typical FMF, only one MEFV mutation was identified and the possibility that more than one autoinflammatory gene may be responsible for their disease was investigated. In the present study, an extensive search for possible mutations in three hereditary recurrent fever (HRF) genes was performed in 128 MEFV heterozygous Greek–Cypriots clinically diagnosed based on their phenotype with FMF-like disease from a previous study. Sequence analysis was performed for MVK, TNFRSF1A and NLRP3 genes which is also known to cause HRFs. In total, three patients were identified with heterozygous mutations and a second mutation in an autoinflammatory gene. Two patients carried a MEFV mutation and a NLRP3 mutation, and an additional third carried a MEFV mutation and a TNFRSF1A mutation. Patient 1 carried MEFV p.[Val726Ala] (NM_000243.2:c.2177T >C) and NLRP3 p.[Val198Met] (NM_001243133.1:c.592G >A) variants and patient 2 carried MEFV p.[Glu148Gln] (NM_000243.2:c.442G >C) variant which is of uncertain significance and NLRP3 p.[Arg176Trp] (NM_001243133.1:c.526C >T). Lastly, patient 3 was identified to carry MEFV p.[Met694Val] (NM_000243.2:c.2080A >G) and TNFRSF1A p.[Arg121Gln] (NM_001065.3:c.362G >A) variants. The results from this study indicate that screening of genes known to cause HRFs in patients already identified with a single MEFV mutation, can reveal quite rare but potentially causative mutational combinations at different loci. Such interaction provide further evidence for possible locus–locus interactions and phenotypes resulting from digenic inheritance.     

Influence of Growth Conditions, Metabolic Inhibitors, and Phenolic Compounds on the ATP Pool in Fomes annosus

The ATP pool of growing fungal mycelia, particularly Fomes annosus, has been determined. The ATP level varied during the different growth phases and correlated with the variations in the economic coefficient. Common uncouplers (at concentrations similar to those used in mitochondrial tests) decreased the ATP pool very rapidly. The size of the pool often fell 50–80% before the O₂ uptake decreased below that of the control and was accompanied by an increasing exudation of inorganic phosphate. Phenolic compounds added to the medium stimulated the lacease activity, generally in combination with a decrease in the ATP level.     

Sunday Lunch in Fiji: Continuity and Transformation in Ideas of the Household

In this article, I compare drawings of "Sunday lunch" produced by Fijian village children in 1990 and 2005 and their responses to prepared drawings in 1982, which show remarkable continuity over time. I suggest this continuity is largely attributable to the ritualization of eating practices. At the same time, the children's data indicate that a substantive, if subtle, change is occurring in ideas of the inclusiveness of the household; I suggest that this change may be a function of an intensification of commodity exchange in day-to-day village life. As the children's data demonstrate, continuity as well as transformation in ideas over time may be understood as a function of the self-same ontogenetic process through which we make sense of our relations with others in the lived world. I argue that such ethnographic studies of ontogeny enable us both to appreciate the material validity of our informants' ideas and to render them analytical.     

Photoperiod and variation in life history traits in core and peripheral populations in the damselfly Lestes sponsa

相似文献   

Cloning of highly polymorphic microsatellites in the horse

We have isolated equine microsatellites by screening a genomic library with (TG)n and (TC)n probes. TG microsatellites were found to be more abundant than TC repeats, with an estimated frequency of one per 100,000bp. Sequence analysis of eight TG-positive clones revealed varying structures of the repeat regions; perfect stretches of TG repeats, imperfect stretches of TG repeats and compound regions of TG and TC repeats. Five loci were analysed by PCR and showed extensive polymorphism; three to seven alleles and heterozygosities of 0.40-0.76 were observed when screening 20-30 unrelated individuals. The high degree of polymorphism, their abundance and the possibility of automating the typing procedure make these loci ideal for standardized paternity testing in the horse. Furthermore, we demonstrate that single hairs can be used as starting material for the PCR analysis.     

Temporal variation in body size and weapon allometry in the New Zealand giraffe weevil

1. Body size and exaggerated traits can show high phenotypic plasticity in response to environmental variation. Trait size can vary among generations but also fluctuate within a breeding season in response to resource availability. 2. This study documents patterns of temporal variation in body and weapon size, and in weapon allometry over 3 years for a wild population of New Zealand giraffe weevils [Lasiorhynchus barbicornis (Fabricius)], the males of which display an extremely elongated rostrum used as a weapon during contests for females. 3. It was predicted that body size and rostrum allometry would decrease during a breeding season, but in spite of significant annual and seasonal variation there was little evidence to support these predictions. Weapon allometry in males was more variable between years and over the breeding season than females, suggesting that male rostrum size may be more susceptible to environmental change than female rostrum size.     

Plant trait responses to grazing – a global synthesis

Herbivory by domestic and wild ungulates is a major driver of global vegetation dynamics. However, grazing is not considered in dynamic global vegetation models, or more generally in studies of the effects of environmental change on ecosystems at regional to global scale. An obstacle to this is a lack of empirical tests of several hypotheses linking plant traits with grazing. We, therefore, set out to test whether some widely recognized trait responses to grazing are consistent at the global level. We conducted a meta‐analysis of plant trait responses to grazing, based on 197 studies from all major regions of the world, and using six major conceptual models of trait response to grazing as a framework. Data were available for seven plant traits: life history, canopy height, habit, architecture, growth form (forb, graminoid, herbaceous legume, woody), palatability, and geographic origin. Covariates were precipitation and evolutionary history of herbivory. Overall, grazing favoured annual over perennial plants, short plants over tall plants, prostrate over erect plants, and stoloniferous and rosette architecture over tussock architecture. There was no consistent effect of grazing on growth form. Some response patterns were modified by particular combinations of precipitation and history of herbivory. Climatic and historical contexts are therefore essential for understanding plant trait responses to grazing. Our study identifies some key traits to be incorporated into plant functional classifications for the explicit consideration of grazing into global vegetation models used in global change research. Importantly, our results suggest that plant functional type classifications and response rules need to be specific to regions with different climate and herbivory history.