Ecological Character Displacement Destabilizes Food Webs

Area of Science:

• Ecology
• Evolutionary Biology
• Theoretical Ecology

Background:

• Ecological character displacement typically increases phenotypic diversity.
• The impact of this adaptive process on food-web dynamics remains understudied.
• Eco-evolutionary feedbacks drive diversification in competing consumers.

Purpose of the Study:

• To investigate how character displacement in consumer attack rates influences resource abundances.
• To assess the effects of character displacement on food-web resilience to perturbations.
• To model the ecological consequences of adaptive consumer evolution.

Main Methods:

• A theoretical model was developed with two competing consumers and two shared resources.
• The model examined character displacement in consumer attack rates.
• Simulations explored different evolutionary trade-offs and foraging scenarios.

Main Results:

• Character displacement consistently strengthened consumer-resource interactions when resources were in different habitats.
• This increased interaction strength led to reduced resource abundances.
• Food webs exhibited decreased resilience to perturbations under character displacement.

Conclusions:

• Adaptive ecological character displacement can impose an ecological cost.
• The process may decrease overall food-web resilience.
• Understanding these trade-offs is crucial for predicting ecosystem stability.