Environmental gradients mediate dispersal evolution during biological invasions

Area of Science:

• Ecology
• Evolutionary Biology
• Invasion Biology

Background:

• Range expansions are often accelerated by rapid evolution of increased dispersal.
• Environmental gradients pose challenges to dispersing individuals, potentially limiting dispersal evolution.

Purpose of the Study:

• To investigate how environmental gradients influence dispersal evolution during range expansions.
• To understand how dispersal evolution modulates invasion speed and predictability.

Main Methods:

• Utilized an eco-evolutionary model to simulate range expansion dynamics.
• Incorporated environmental gradients and their effects on individual fitness.
• Parameterized the model with empirical data from an invertebrate range expansion.

Main Results:

• Environmental gradients opposed the evolution of increased dispersal, sometimes favoring reduced dispersal.
• Reduced dispersal, counterintuitively, could lead to faster invasion by minimizing maladaptive gene flow and aiding adaptation.
• Environmental gradients significantly dampened the impact of dispersal evolution on invasion speed and variance compared to homogenous landscapes.

Conclusions:

• Environmental gradients play a critical role in shaping dispersal evolution during invasions.
• The interplay between environmental gradients and dispersal evolution affects invasion speed and predictability.
• Findings have implications for predicting and managing biological invasions.