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Published on: January 12, 2017
The evolution of host protection by vertically transmitted parasites
Edward O Jones1, Andrew White, Michael Boots
1Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK. e.o.jones@abdn.ac.uk
Proceedings. Biological Sciences
|September 24, 2010
Summary
Vertically transmitted symbionts may evolve to protect hosts from harmful parasites, especially those reducing reproduction. This protection can drive the evolution of more virulent parasites in nature.
Area of Science:
- Evolutionary biology
- Parasitology
- Symbiosis
Background:
- Hosts frequently harbor multiple parasites, leading to interspecific competition and coevolution.
- Vertically transmitted symbionts can offer protection against other infections, potentially explaining their prevalence.
Purpose of the Study:
- To theoretically investigate the conditions favoring the evolution of host protection by vertically transmitted symbionts.
- To analyze the selective effects of such protective symbionts on other parasite species.
Main Methods:
- Theoretical modeling of host-parasite-symbiont interactions.
- Analysis of evolutionary dynamics under different transmission modes and virulence levels.
Main Results:
- Protection evolves most readily against horizontally transmitted parasites that significantly reduce host fecundity.
- Protection is favored when parasites are highly transmissible and cause intermediate, not high, virulence.
- Intermediate protection selects for more virulent horizontally transmitted parasites.
Conclusions:
- Protective symbionts can be a major selective force, potentially driving parasite virulence evolution.
- The evolution of protection is influenced by parasite transmission, virulence, and host lifespan, especially in coevolutionary scenarios.
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