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Updated: Jun 26, 2026
07:17
Culturing and Genetically Manipulating Entomopathogenic Nematodes
Published on: March 31, 2022
How can your parasites become your allies?
Simon Fellous1, Lucie Salvaudon
1Department of Entomology, Cornell University, Ithaca, NY 14853, USA. simonfellous@free.fr
Trends in Parasitology
|February 3, 2009
Summary
Parasites can benefit hosts by granting new abilities, fostering mutualism more effectively than trait modification. This can lead to evolved dependence, shaping long-term host-parasite relationships.
Area of Science:
- Evolutionary biology
- Parasitology
- Mutualism
Background:
- Parasitic infections are typically harmful but can offer benefits to hosts.
- Parasites may introduce novel functions or alter host life-history traits.
Purpose of the Study:
- To explore how parasites can benefit hosts.
- To determine the evolutionary likelihood of mutualism through parasite-provided abilities versus trait modification.
- To examine the role of evolved dependence in mutualistic relationships.
Main Methods:
- Theoretical analysis of evolutionary pathways.
- Comparative study of host-parasite interactions.
- Examination of life-history trait evolution.
Main Results:
- Parasites providing new host abilities promote lasting mutualism more than trait alteration.
- Hosts are less capable of evolving novel functions independently compared to adjusting life-history traits.
- Evolved dependence, where hosts lose the ability to survive without parasites, shapes current mutualisms.
Conclusions:
- Parasite-conferred novel abilities are a strong driver for the evolution of mutualism.
- Evolved dependence is a key factor in the long-term stability and nature of mutualistic relationships.
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