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Published on: January 12, 2017
Gene flow and the coevolution of parasite range
Scott L Nuismer1, Mark Kirkpatrick
11 University Station C0930, University of Texas, Austin, Texas 78712, USA. nuismer@mail.utexas.edu
Summary
Host gene flow significantly impacts parasite geographic ranges, influencing population densities and potentially leading to extinction. Demographic compensation can decouple parasite adaptation from host gene flow dynamics.
Area of Science:
- Evolutionary biology
- Parasitology
- Ecological modeling
Background:
- Parasite geographic ranges are often smaller than those of their hosts.
- Understanding the evolutionary and demographic factors driving these range differences is crucial.
Purpose of the Study:
- To investigate the evolutionary mechanisms behind restricted parasite geographic ranges.
- To model the interplay between host gene flow, parasite demography, and coevolution.
Main Methods:
- A simple mathematical model coupling coevolution and demography was developed.
- The model considers two interconnected habitats and quantitative traits for coevolution.
- Host gene flow rates were analyzed as a key variable.
Main Results:
- Host gene flow was identified as a critical determinant of parasite geographic range.
- Variations in host gene flow rates caused significant shifts in parasite population densities and range sizes.
- Extreme fluctuations in host gene flow could result in parasite extinction.
Conclusions:
- Demographic compensation allows parasite density shifts with minimal impact on host adaptation.
- Reciprocal host-parasite adaptation can become independent of host gene flow rates.
- Host gene flow is a key factor shaping parasite distribution and persistence.
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