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Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Speciation driven by natural selection in Drosophila
1Department of Ecology and Evolution, University of Chicago, Illinois 60637, USA.
Nature
|June 22, 1995
Summary
Speciation by reinforcement strengthens reproductive isolation between species. In Drosophila pseudoobscura fruitflies, females evolved greater mating preference, reducing harmful hybridization with sibling species.
Area of Science:
- Evolutionary biology
- Speciation research
- Behavioral ecology
Background:
- Reinforcement is a key evolutionary mechanism driving speciation by enhancing reproductive isolation.
- This process reduces maladaptive hybridization between diverging populations.
- Recent studies have questioned the empirical support for reinforcement as a driver of speciation.
Purpose of the Study:
- To provide experimental evidence for speciation by reinforcement.
- To investigate the role of natural selection in strengthening sexual isolation.
- To examine the interaction between Drosophila pseudoobscura and Drosophila persimilis.
Main Methods:
- Comparative analysis of mating preferences in Drosophila pseudoobscura populations.
- Assessing the frequency of hybridization events.
- Evaluating female mate choice in the presence of a sibling species.
Main Results:
- Drosophila pseudoobscura females demonstrated evolved increased sexual isolation from Drosophila persimilis.
- Natural selection appears to favor reduced hybridization with the sibling species.
- Evidence supports reinforcement as a mechanism completing reproductive isolation.
Conclusions:
- This study provides a compelling example of speciation by reinforcement in a natural population.
- Natural selection effectively reduces maladaptive hybridization, promoting reproductive isolation.
- The findings reaffirm the significance of reinforcement in the speciation process.
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