Assessing frequency-dependent seed size selection: a field experiment

Frequency and Density-Dependent Selection on Life-History Strategies – A Field Experiment

Negative frequency-dependence, which favors rare genotypes, promotes the maintenance of genetic variability and is of interest as a potential explanation for genetic differentiation. Density-dependent selection may also promote cyclic changes in frequencies of genotypes. Here we show evidence for both density-dependent and negative frequency-dependent selection on opposite life-history tactics ...

Seed Size Selection in Heteromyids: A Second Look

Frequency-dependent Chemotactic Target Selection

Chemotaxis usually involves cellular motion towards an exogenous, often static, source of chemoattractant. We demonstrate an enhanced mechanism in which a single particle (the cell) releases a chemical that diffuses to fixed particles (targets) and signals the production of another chemical by the targets. This secondary chemical acts as the cell’s chemoattractant. To reach a single target, we ...

Optimization under frequency-dependent selection.

We consider a model of frequency-dependent selection, which we refer to as the Wildcard Model. A variety of more specific models, representing quite diverse biological situations, are covered by the Wildcard Model as particular cases. Two very different particular models that are subsumed by the Wildcard Model are the game theoretically motivated two-phenotype model of Lessard [Lessard, S.,1984...

Sambucina Maintained by Differential Seed Viability Instead of Frequency-dependent Selection?

The European rewardless, bee-pollinated orchid Dactylorhiza sambucina commonly produces yellow-flowered and purple-flowered individuals in frequencies that range from balanced (per population) to very unbalanced, with parts of the species’ range entirely monochromatic. We studied male and female reproductive success of the two morphs in 22 populations in the Czech Republic, relating it to morph...