On Male Harm: How It Is Measured and How It Evolves in Different Environments

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Sexual selection

Background:

• Male harm to females is a widespread phenomenon, but its intensity varies significantly across populations and species.
• Environmental factors can influence the evolution and expression of male harm, potentially through changes in sexual interaction dynamics.

Purpose of the Study:

• To investigate how female control over sexual interactions influences the evolution of male harm.
• To compare two common approaches for studying male harm and their limitations.
• To examine both evolved and plastic responses to environmental variation in male harm.

Main Methods:

• Experimental evolution of Drosophila melanogaster populations in environments with differing levels of female control over mating.
• Testing for evolved differences in male harm across these experimental populations.
• Assessing plastic changes in male harm when males and females interact in different environments.

Main Results:

• Populations evolved in environments with greater female control exhibited reduced male harm.
• Absence of mate competition also led to an evolved reduction in male harm.
• A plastic effect was observed, where males previously exhibiting harm showed reduced harm in environments with greater female control.

Conclusions:

• Female control over sexual interactions is a significant factor in the evolution of reduced male harm.
• Both evolved and plastic mechanisms contribute to the environmental modulation of male harm.
• The study highlights the importance of considering environmental context and methodology when assessing male harm.