Evolution of mating behavior between two populations adapting to common environmental conditions

Area of Science:

• Evolutionary Biology
• Behavioral Ecology
• Genetics

Background:

• Differentiated populations in contrasting environments may face altered reproductive isolation when encountering novel common environments.
• Abiotic factors influencing this isolation have been historically overlooked in research.
• Previous work established significant life-history and chromosomal differentiation in the studied Drosophila subobscura populations.

Purpose of the Study:

• To investigate the rapid evolution of mating behaviors in Drosophila subobscura populations adapting to a common laboratory environment.
• To examine how simulated population encounters at different evolutionary time points modify reproductive isolation.
• To fill the research gap concerning the role of abiotic factors in modifying population isolation.

Main Methods:

• Experimental evolution of three replicates of two Drosophila subobscura populations.
• Adaptation to a common laboratory environment.
• Simulated population encounters at three distinct time points during adaptation.

Main Results:

• Initial differentiation observed in assortative mating and male mating rate, but not female mating latency.
• Mating frequency increased across experimental evolution in both populations.
• Assortative mating remained constant in one population, while disassortative mating decreased in the other.
• Differences in male mating rate persisted across generations.

Conclusions:

• Mating behavior evolves rapidly in response to adaptation to a common abiotic environment.
• The evolutionary pattern of mating behavior is complex and does not mirror the rapid convergence seen in life-history traits.
• This study highlights the significant impact of abiotic environmental adaptation on the evolution of reproductive isolation and mating behaviors.