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Species' borders and dispersal barriers.
Emma E Goldberg1, Russell Lande
1Division of Biological Sciences, University of California, San Diego, La Jolla, California 92903, USA. goldberg@biomail.ucsd.edu
The American Naturalist
|September 18, 2007
Summary
Dispersal barriers can influence species range limits. Reduced dispersal attracts borders maintained by competition or hybridization, but repels borders shaped by local adaptation and gene flow.
Area of Science:
- Ecology
- Evolutionary Biology
- Population Genetics
Background:
- Species' range limits are shaped by complex interactions including physical, historical, ecological, and evolutionary factors.
- Understanding these factors is crucial for predicting species' responses to environmental changes and for conservation efforts.
Purpose of the Study:
- To investigate how partial dispersal barriers affect the location of borders between similar species.
- To determine the conditions under which species' borders are attracted to or repelled from regions of reduced dispersal.
Main Methods:
- Utilized spatial models incorporating competition, hybridization, and local adaptation.
- Examined the interplay between dispersal limitations and ecological/evolutionary processes at species borders.
Main Results:
- Dispersal barriers were found to attract borders maintained by competition or hybridization.
- Conversely, borders strongly influenced by local adaptation and gene flow were repelled from dispersal barriers.
Conclusions:
- Spatial models demonstrate how dispersal barriers interact with ecological and evolutionary forces to shape species' range limits.
- These findings elucidate mechanisms contributing to the coincidence of range limits for multiple species.
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