Insecticide resistance evolution and assisted gene flow interact to shape the evolution of plasticity

Area of Science:

• Evolutionary biology
• Genetics
• Ecology

Background:

• Phenotypic plasticity is crucial for adapting to environmental changes.
• The rapid evolution of plasticity and the forces driving it remain poorly understood.
• Understanding these dynamics is vital for predicting species' responses to environmental shifts.

Purpose of the Study:

• To investigate how insecticide resistance selection and gene flow impact the evolution of phenotypic plasticity in Drosophila melanogaster.
• To determine if genetic diversity, facilitated by assisted gene flow, influences adaptive plasticity.
• To explore potential trade-offs between trait evolution and plasticity evolution.

Main Methods:

• A replicated field experiment involving Drosophila melanogaster populations adapted to insecticide exposure.
• Implementation of assisted gene flow with varying genetic diversity.
• Common garden experiments to assess plasticity across temperature and insecticide treatments.

Main Results:

• Both insecticide resistance evolution and gene flow significantly influenced plasticity across multiple traits.
• Maladaptive plasticity was observed in resistant and gene flow-restricted populations, suggesting trait-plasticity trade-offs.
• Assisted gene flow reduced maladaptive plasticity, possibly by alleviating genetic constraints.

Conclusions:

• Trait evolution and plasticity evolution are dynamically interconnected.
• Genetic diversity, enhanced by gene flow, plays a key role in shaping adaptive plasticity.
• Findings have implications for conserving populations facing environmental change and genetic diversity loss.