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The relationship between parasite virulence and environmental persistence: a meta-analysis
1Department of Zoology,University of Oxford,Mansfield Road, Oxford, OX1 3SZ,UK.
Parasitology
|February 20, 2019
Summary
Parasite virulence evolution is complex. While some theories suggest environmental persistence increases virulence, this meta-analysis found the relationship depends on parasite type, with viruses showing trade-offs and bacteria/fungi showing positive correlations.
Area of Science:
- Evolutionary biology
- Parasitology
- Ecology
Background:
- The evolution of extreme parasite virulence is not fully understood.
- Two main hypotheses exist: the 'sit and wait' hypothesis predicts higher virulence with environmental persistence, while the 'resource allocation' hypothesis predicts a trade-off.
Purpose of the Study:
- To conduct a meta-analysis on existing data to investigate the relationship between parasite environmental persistence and virulence.
- To test the predictions of the 'sit and wait' hypothesis specifically.
Main Methods:
- A meta-analysis was performed on published data concerning parasite virulence and environmental persistence.
- A subset of the data was analyzed to focus on studies directly testing the 'sit and wait' hypothesis.
Main Results:
- Empirical evidence supports both the 'sit and wait' and 'resource allocation' hypotheses.
- The observed relationship is strongly dependent on the parasite's taxonomic group.
- Viruses generally exhibit resource allocation trade-offs, while bacterial and fungal parasites show a positive correlation between persistence and virulence.
Conclusions:
- The evolution of parasite virulence and environmental persistence is context-dependent, varying significantly across different parasite types.
- Understanding these differing evolutionary strategies is crucial for predicting parasite dynamics and impacts.
Keywords:
Curse of the pharaohhost–parasite interactiontrade-offtransmissionvirulencevirulence evolutionMore Related Videos
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