Mixed support for an alignment between phenotypic plasticity and genetic differentiation in damselfly wing shape

Area of Science:

• Evolutionary Biology
• Ecology
• Genetics

Background:

• Phenotypic plasticity's role in adaptation to environmental change is debated.
• Understanding the interplay between genetic differentiation and plasticity is crucial for predicting evolutionary trajectories.

Purpose of the Study:

• To investigate the relationship between genetic differentiation and phenotypic plasticity in damselfly wing shape.
• To determine if plasticity facilitates or hinders adaptation across a latitudinal gradient with varying time constraints.

Main Methods:

• Reciprocal transplant experiment with damselflies (Lestes sponsa) from northern and southern European populations.
• Laboratory rearing simulating time-constrained (northern) and unconstrained (southern) photoperiods and temperatures.
• Geometric morphometrics analysis of adult wing shape.

Main Results:

• Significant differences in wing shape between northern and southern damselfly populations under native conditions.
• Evidence of phenotypic plasticity in wing shape with population-specific responses (G × E interactions).
• Plastic responses were stronger in the northern population, with varied directions of change; population differences in wing shape were 2-4 times stronger than plastic effects.

Conclusions:

• Mixed support for the hypothesis that environmental plasticity and genetic differentiation are aligned.
• Alignment varied depending on population and rearing environment, particularly for forewings under time-constrained conditions.
• Environmental time constraints and differential selection pressures (natural and sexual) on forewings and hindwings may influence these patterns.