Although an interspecific trade-off between competitive and colonizing ability can permit multispecies coexistence, whether this mechanism controls the structure of natural systems remains unresolved. We used models to evaluate the hypothesized importance of this trade-off for explaining coexistence and relative abundance patterns in annual plant assemblages. In a nonspatial model, empirically ...

We use the optimal foraging theory to study coexistence between two plant species and a generalist pollinator. We compare conditions for plant coexistence for non-adaptive vs. adaptive pollinators that adjust their foraging strategy to maximize fitness. When pollinators have fixed preferences, we show that plant coexistence typically requires both weak competition between plants for resources (...

The increasing evidence of coexistence of cryptic species with no recognized niche differentiation has called attention to mechanisms reducing competition that are not based on niche-differentiation. Only sex-based mechanisms have been shown to create the negative feedback needed for stable coexistence of competitors with completely overlapping niches. Here we show that density-dependent sexual...

Most prior studies on the role of dispersal in the coexistence of competing species have emphasized the need for trade-offs between competitive and colonizing abilities for coexistence. Theoretical studies of the evolution of dispersal recently have revealed an alternative mechanism for the coexistence of species differing solely in dispersal rates in spatially extended systems. We present an a...

Seed purity, more appropriately seed product integrity, is maintained within a framework of regulatory (labeling) requirements through the Federal Seed Act, quality standards, seed testing performed by accredited entities, quality management practices, and production under principles and practices of coexistence. Cooperation among seed developers, seed producers, and growers at the local field ...

The prevalence of intraguild predation (IGP) in productive environments has long puzzled ecologists. Theory predicts the exclusion of intraguild prey from such environments, but data consistently defy this expectation. This suggests that coexistence mechanisms at high resource productivity may differ from those at lower productivity. Here I present a mathematical model that investigates multipl...

A number of mechanisms have been proposed to explain the coexistence of species engaging in exploitative competition. The Armstrong-McGehee mechanism relies on different levels of nonlinearity in functional response between competing consumers and their ability to avoid competitive exclusion through temporal resource partitioning during endogenously generated fluctuations. While previous studie...

Limitation of resources has been recently introduced as a mechanism for the survival and coexistence of cooperators with defectors in well-mixed populations. Here we examine the same model on a scale-free network. A prisoner’s dilemma game on a scale-free network has shown coexistence of cooperators and defectors for the entire range of parameters. Our results show that by introducing the netwo...

Abstract A Lennard–Jones model of a binary dense liquid (A,B) with a symmetrical miscibility gap is investigated by means of computer simulation methods. Semigrand–canonical Monte Carlo simulations yield the phase diagram in the T–x plane (T : temperature, x: concentration of A or B particles) as well as equilibrated configurations at coexistence. Then Molecular Dynamics simulations use these c...

introduction: digital clubbing is a clinically descriptive term, referring to bulbous uniform swelling of the soft tissue of the terminal phalanx of a digit with subsequent loss of the normal angle between the nail and the nail bed. it is associated with various underlying pulmonary, cardiovascular, neoplastic, infectious, hepatobiliary, mediastinal, endocrine, and gastrointestinal diseases. fi...