Empirical Support for Optimal Virulence in a Castrating Parasite
2006
Bacterial Parasite Balances Host Infection
publication
Evidence: high
Author Information
Author(s): Knut Helge Jensen, Dieter Ebert
Hypothesis
The study investigates the relationship between parasite fitness and virulence in the castrating bacterium Pasteuria ramosa infecting water fleas.
Conclusion
The study found that maximum parasite fitness derives from an intermediate level of virulence.
Supporting Evidence
- The researchers found significant variation in parasite virulence.
- The highest spore production was detected in Daphnia expiring at middle age.
- Genetic variation in the parasite can influence variation in virulence.
Takeaway
Parasites want to make sure their hosts stay alive long enough to spread their babies, so they don't want to be too mean or too nice.
Methodology
The researchers exposed Daphnia clones to bacterial spores and tracked individual host mortality to determine the relationship between virulence and lifetime production of transmission-stage parasites.
Participant Demographics
The study involved water fleas (Daphnia magna) as hosts.
Digital Object Identifier (DOI)
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