Evolution of density- and patch-size-dependent dispersal rates.

Area of Science:

• Ecology
• Evolutionary Biology
• Population Dynamics

Background:

• Metapopulation dynamics are crucial for species survival.
• Understanding evolutionarily stable (ES) dispersal is key to predicting population persistence.
• Density dependence influences population growth and dispersal behavior.

Purpose of the Study:

• To derive a nonlinear expression for ES dispersal rates in metapopulations.
• To investigate the effects of density dependence, environmental fluctuations, and dispersal mortality on dispersal evolution.
• To test analytical predictions using spatially explicit simulations.

Main Methods:

• Marginal value approach for deriving theoretical dispersal rates.
• Spatially explicit, individual-based simulation experiments.
• Analysis of density-dependent population growth models.

Main Results:

• Individual dispersal rates decrease with patch capacity and increase with population density.
• Dispersal rates are significantly influenced by dispersal mortality and inter-patch density variation.
• Environmental fluctuations and population growth rate are key drivers of density variation.

Conclusions:

• Analytical predictions for ES dispersal rates are supported by simulation results.
• Dispersal mortality and inter-patch density variation are dominant factors in metapopulation dispersal.
• Kin competition has negligible impact on ES dispersal except at low rates.