The leaf economics spectrum (LES) describes a major axis of plant functional trait variation worldwide, defining suites of leaf traits aligned with resource-acquisitive to resource-conservative ecological strategies. The LES has been interpreted to arise from leaf-level trade-offs among ecophysiological traits common to all plants. However, it has been suggested that the defining leaflevel trad...

this study was conducted with the main purpose of investigating genetic variation among 13 selected sweetcherry (prunus avium cv. siah mashhad) genotypes, i.e., the most important iranian sweet cherry cultivars based on their pomological, morphological, and phonological characteristics. the experiment was laid out in a randomized complete block design with three replications at khorasan-e-razav...

In this study, we used data from temperate grassland plant communities in Alberta, Canada to test two longstanding hypotheses in ecology: 1) that there has been correlated evolution of the leaves and roots of plants due to selection for an integrated whole-plant resource uptake strategy, and 2) that trait diversity in ecological communities is generated by adaptations to the conditions in diffe...

Variation in somatic growth rates is of great interest to biologists because of the relationship between growth and other fitness-determining traits, and it results from both genetic and environmentally induced variation (i.e. plasticity). Theoretical predictions suggest that mean somatic growth rates and the shape of the reaction norm for growth can be influenced by variation in predator-induc...

Communication signals often vary between individuals, even when one expects selection to favour accuracy and precision, such as the honey bee waggle dance, where foragers communicate to nestmates the direction and distance to a resource. Although many studies have examined intra-dance variation, or the variation within a dance, less is known about inter-dance variation, or the variation between...

Consumer-resource interactions are a central issue in evolutionary and community ecology because they play important roles in selection and population regulation. Most consumers encounter resource variation at multiple scales, and respond through phenotypic plasticity in the short term or evolutionary divergence in the long term. The key traits for these responses may influence resource acquisi...

Growth of ungulate populations is typically most sensitive to survival of neonates, which in turn is influenced by maternal nutritional condition and trade-offs in resource selection and avoidance of predators. We assessed whether resource use, multi-predator risk, maternal nutritional effects, hiding cover, or interactions among these variables best explained variation in daily survival of fre...

Epidemiologists increasingly realize that species interactions (e.g. selective predation) can determine when epidemics start and end. We hypothesize here that resource quality can also strongly influence disease dynamics: epidemics can be inhibited when resource quality for hosts is too poor and too good. In three lakes, resource quality for the zooplankton host (Daphnia dentifera) was poor whe...

Natural populations often show variation in traits that can affect the strength of interspecific interactions. Interaction strengths in turn influence the fate of pairwise interacting populations and the stability of food webs. Understanding the mechanisms relating individual phenotypic variation to interaction strengths is thus central to assess how trait variation affects population and commu...