Competition and the Effect of Spatial Resource Heterogeneity on Evolutionary Diversification

Area of Science:

• Ecology
• Evolutionary Biology
• Population Genetics

Background:

• Competition for resources is a key driver of evolutionary diversification.
• Spatial resource heterogeneity can influence ecological and evolutionary dynamics.
• Disruptive selection favors trait polymorphism, potentially leading to speciation.

Purpose of the Study:

• To model how spatial resource heterogeneity affects disruptive selection.
• To identify conditions favoring evolutionary diversification of resource exploitation strategies.
• To compare disruptive selection in identical versus heterogeneous resource patches.

Main Methods:

• A mathematical model simulating a single species in two connected patches.
• Patches differ in resource type, affecting population dynamics.
• Analysis of conditions leading to disruptive selection and character displacement.

Main Results:

• Disruptive selection conditions mirror character displacement in identical patches.
• Heterogeneous patches can have more or less stringent disruptive selection conditions.
• Spatial heterogeneity can decrease the likelihood of evolutionary diversification.

Conclusions:

• Spatial resource heterogeneity's effect on disruptive selection depends on demographic parameters.
• Low migration rates between patches consistently enhance disruptive effects.
• Resource heterogeneity can paradoxically reduce evolutionary diversification potential.