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Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions
Published on: August 31, 2018
Evidence for a trade-off between host-range breadth and host-use efficiency in aphid parasitoids
Cory S Straub1, Anthony R Ives, Claudio Gratton
1Department of Entomology, University of Wisconsin-Madison, 53706, USA. cstraub@ursinus.edu
The American Naturalist
|April 5, 2011
Summary
Generalist species may not be masters of all trades. This study found relative specialists were more abundant than generalists on shared hosts, suggesting a fitness cost for generalist species.
Area of Science:
- Ecology
- Evolutionary Biology
- Behavioral Ecology
Background:
- The 'jack-of-all-trades is a master of none' adage suggests generalists incur fitness costs.
- Empirical evidence for such generalist fitness costs is limited.
- Understanding trade-offs between host-range breadth and host-use efficiency is crucial in ecology.
Purpose of the Study:
- To investigate if relative specialists are more abundant than generalists on shared hosts.
- To determine if a generalist-specialist trade-off exists in aphid parasitoids.
- To assess the impact of host-range breadth versus host number on generalist fitness.
Main Methods:
- Utilized published data from a long-term field survey of aphid parasitoids.
- Quantified parasitoid abundance on shared hosts.
- Employed a specialization measure accounting for taxonomic differences among hosts.
Main Results:
- Relative specialists were found to be more abundant than generalists on shared hosts.
- This pattern was significant only when host specialization accounted for taxonomic breadth.
- Parasitoid abundance correlated with host taxonomic breadth, not just the number of hosts.
Conclusions:
- A generalist-specialist trade-off exists in this group of aphid parasitoids.
- The fitness cost for generalists is influenced by the taxonomic breadth of hosts used.
- Host-range breadth, rather than the sheer number of host species, drives the generalist cost.
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