Dodge, Duck, Dip, Dive & Dependence: Using Dodgeball to Explore Frequency Dependent Selection

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 ...

Transformation to dip-dependent Common Image Gathers

We introduce a new transform of offset-domain Common Image Gathers (CIGs) obtained by wavefield-continuation migration methods. This transformation can be applied to either horizontal-offset CIGs or vertical-offset CIGs. It overcomes the limitations that both kinds of CIGs suffer in the presence of a wide range of reflectors’ dips. The result of our transformation is an image cube that is equiv...

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...

To dive or not to dive.

Modeling frequency-dependent selection with an application to cichlid fish.

Negative frequency-dependent selection is a well known microevolutionary process that has been documented in a population of Perissodus microlepis, a species of cichlid fish endemic to Lake Tanganyika (Africa). Adult P. microlepis are lepidophages, feeding on the scales of other living fish. As an adaptation for this feeding behavior P. microlepis exhibit lateral asymmetry with respect to jaw m...