Ecologists have long observed that consumers can maintain species diversity in communities of their prey. Many theories of how consumers mediate diversity invoke a tradeoff between species' competitive ability and their ability to withstand predation. Under this constraint, the best competitors are also most susceptible to consumers, preventing them from excluding other species. However, empiri...

Linking competitive outcomes to environmental conditions is necessary for understanding species' distributions and responses to environmental change. Despite this importance, generalizable approaches for predicting competitive outcomes across abiotic gradients are lacking, driven largely by the highly complex and context-dependent nature of biotic interactions. Here, we present and empirically ...

(1) Competitive ability can be compared between species in two ways: effect of different neighbour species on performance of a single target species or response of different arget species to a single neighbour species. In a 5-week glasshouse experiment, an additive design was used for all combinations of seven species as both target and neighbour species to determine if there were consistent hi...

Geographic variation in species interactions can have major effects on distributions. Effects of such variation can be particularly evident for invasive species, in which variation in competitive ability can influence invasive success and impacts. We tested the hypothesis that coexistence or exclusion of the resident mosquito Aedes aegypti results from variation among local populations of the i...

Body size influences many physiological and ecological processes, and thus adaptive change in body size may hold diverse consequences for individuals. For amphipods in the Hyalella azteca species complex, divergence in body size appears to be driven by adaptation to disparate regimes of size-biased mortality experienced in different habitat types. Here I ask how size and size-related traits inf...

in order to investigate the effects of weeds interference on yield and yield components of different genotypes of common bean, an experiment was conducted as split plot based on randomized complete block design with three replications at agricultural research station of tabriz university, in 2011. the main plots were eight genotypes of different types of common bean including red bean, (cv. gho...

BACKGROUND AND AIMS Differences in competitive ability between the sexes of dioecious plants are expected as a result of allocation trade-offs associated with sex-differential reproductive costs. However, the available data on competitive ability in dioecious plants are scarce and contradictory. In this study sexual competition was evaluated using the dioecious plant Antennaria dioica in a comm...

Invasive plants are sometimes considered to be more competitive than their native conspecifics, according to the prediction that the invader reallocates resources from defense to growth due to liberation of natural enemies ['Evolution of Increased Competitive Ability' (EICA) hypothesis]. However, the differences in competitive ability may depend on the identity of competitors. In order to test ...

The evolution of increased competitive ability (EICA) hypothesis proposes that invasive species evolve decreased defense and increased competitive ability following natural enemy release. Previous tests of EICA examined the result of evolution by comparing individuals from home and introduced ranges, but no previous study of this hypothesis has examined the process of evolution by analyzing pat...