Interactions between spatial and temporal scales in the evolution of dispersal rate

TL;DR

This study models how spatial and temporal environmental scales influence the evolution of dispersal strategies, revealing interactions that maintain polymorphism and predicting dispersal loss in specific environmental contexts.

Contribution

It introduces a model exploring the interaction between spatial and temporal scales in dispersal evolution, highlighting scale-dependent polymorphism maintenance.

Findings

Interaction between group and individual selection affects dispersal evolution.

Polymorphism in dispersal strategies is maintained depending on environmental scales.

Loss of dispersal abilities is predicted to be more frequent in continuous or stable environments.

Abstract

The evolution of dispersal rate is studied with a model of several local populations linked by dispersal. Three dispersal strategies are considered where all, half, or none of the offspring disperse. The spatial scale (number of patches) and the temporal scale (probability of local extinction) of the environment are critical in determining the selective advantage of the different dispersal strategies. The results from the simulations suggest that an interaction between group selection and individual selection results in a different outcome in relation to the spatial and temporal scales of the environment. Such an interaction is able to maintain a polymorphism in dispersal strategies. The maintenance of this polymorphism is also scale-dependent. This study suggests a mechanism for the short-term evolution of dispersal, and provides a testable prediction of this hypothesis, namely that loss of dispersal abilities should be more frequent in spatially more continuous environments, or in temporally more stable environments.