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The coevolution of virulence: tolerance in perspective
Tom J Little1, David M Shuker, Nick Colegrave
1Institute of Evolutionary Biology, Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom. tom.little@ed.ac.uk
Plos Pathogens
|September 15, 2010
Summary
Host tolerance evolves, impacting parasite populations and driving coevolution. Understanding these host-parasite dynamics is crucial for disease control and biotic partnership theories.
Area of Science:
- Evolutionary biology
- Ecology
- Pathogen-host interactions
Background:
- Coevolutionary interactions involve reciprocal genetic changes between interacting species.
- Research on host-parasite evolution has often prioritized parasite-driven changes over host responses.
- Host tolerance, the ability to reduce disease impact without reducing pathogen load, offers a host-centric perspective.
Purpose of the Study:
- To explore the broader implications of host tolerance in coevolutionary dynamics.
- To emphasize the need for comprehensive host fitness measures within tolerance studies.
- To investigate the potential for parasite counter-adaptation to host tolerance.
Main Methods:
- Theoretical framework development for host tolerance.
- Analysis of coevolutionary consequences of host tolerance.
- Consideration of parasite counter-adaptation mechanisms.
Main Results:
- Host tolerance can alter selection pressures on parasite populations.
- Parasite evolution can be triggered by host tolerance, even without direct antagonism.
- Host tolerance necessitates studying reciprocal adaptations in biotic partnerships.
Conclusions:
- A cohesive theory of biotic partnerships requires integrating host tolerance and parasite counter-adaptation.
- Effective disease control strategies must account for the coevolutionary consequences of host tolerance.
- Future research should focus on the interplay between host tolerance and parasite evolution.
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