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Dispersal evolution diminishes the negative density dependence in dispersal
Abhishek Mishra1, Partha Pratim Chakraborty1,2, Sutirth Dey1
1Population Biology Laboratory, Biology Division, Indian Institute of Science Education and Research, Pune, Pune, 411 008, India.
Evolution; International Journal of Organic Evolution
|July 30, 2020
Summary
Density-dependent dispersal (DDD) patterns evolved differently in fruit flies. Selection for dispersal changed negative DDD in controls to positive DDD in selected groups, impacting spatial ecology.
Area of Science:
- Ecology
- Evolutionary Biology
- Population Dynamics
Background:
- Density-dependent dispersal (DDD) influences population dynamics, spatial spread, and invasiveness.
- Empirical evidence for the evolution of DDD patterns is scarce, despite the confirmed rapid evolution of dispersal traits in various taxa.
- Understanding DDD evolution is crucial for predicting range expansion and spatial ecology.
Purpose of the Study:
- To investigate the relationship between dispersal evolution and density-dependent dispersal (DDD) patterns.
- To compare DDD patterns in dispersal-selected populations versus non-selected controls in Drosophila melanogaster.
- To assess how evolutionary changes in dispersal affect DDD and its implications for spatial ecology.
Main Methods:
- Utilized a long-term experimental evolution study on Drosophila melanogaster.
- Compared DDD patterns between four populations selected for increased dispersal and their non-selected control populations.
- Analyzed sex-specific differences in DDD patterns.
Main Results:
- Control populations exhibited negative DDD, more pronounced in females than males.
- Dispersal-selected populations showed positive DDD, with no significant sex difference.
- Evolutionary change in DDD direction was influenced by the initial DDD pattern.
Conclusions:
- Dispersal evolution can alter the direction of density-dependent dispersal (DDD).
- Initial DDD patterns play a key role in the direction of evolutionary change.
- DDD evolution has significant implications for spatial ecology and population spread.
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