The relationship between genotype, developmental stability and mating performance: disentangling the epigenetic...

Area of Science:

• Evolutionary Biology
• Behavioral Ecology
• Developmental Biology

Background:

• Developmental stability (DS) is hypothesized to provide an advantage in sexual competition.
• Fluctuating asymmetry (FA), a measure of developmental instability, has been proposed as an indicator of genetic quality.

Purpose of the Study:

• To test the hypothesis that developmental stability confers an advantage in mate competition using Drosophila immigrans.
• To explore potential epigenetic factors influencing this relationship.
• To investigate the link between fluctuating asymmetry and sexual performance.

Main Methods:

• Estimated heritability of sternopleural bristle fluctuating asymmetry (FA) in replicate genetic lines of Drosophila immigrans.
• Assessed the relationship between positional FA (PFA) and components of sexual performance (copulation latency, duration, frequency) in individual males.
• Compared sexual performance between high-DS and low-DS lines, and analyzed results after statistically controlling for individual asymmetry.

Main Results:

• A significant heritability (0.10) for sternopleural bristle FA was found.
• Individual PFA showed a positive correlation with copulation latency and duration, but not frequency.
• High-DS lines exhibited shorter copulation latency and duration; however, these line differences vanished when individual asymmetry was controlled.

Conclusions:

• Deficits in the developmental stability of a specific trait can impair individual sexual performance.
• The findings challenge the hypothesis that FA is a reliable indicator of overall genetic quality.
• Further research is needed to define the epigenetic factors underlying developmental stability and its impact on sexual selection.