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On oscillations and flutterings-A reply to Hamm and Fordyce
Niklas Janz1, Mariana P Braga2, Niklas Wahlberg3,4
1Department of Zoology, Stockholm University, 106 91, Stockholm, Sweden. niklas.janz@zoologi.su.se.
Evolution; International Journal of Organic Evolution
|April 21, 2016
Summary
The oscillation hypothesis explains insect diversification through host range changes. A recent study misinterpreting this hypothesis and using flawed methods incorrectly concluded it was unsupported, necessitating future research with improved approaches.
Area of Science:
- Evolutionary biology
- Ecology
- Entomology
Background:
- Plant-feeding insect diversification is a key example of evolutionary radiation.
- The oscillation hypothesis proposes host range expansions and contractions drive diversification.
- A recent study by Hamm and Fordyce challenged the oscillation hypothesis.
Purpose of the Study:
- To critique the methodology and interpretation of Hamm and Fordyce's study.
- To clarify the oscillation hypothesis and its predictions.
- To re-evaluate the data using corrected methods.
Main Methods:
- Critique of Hamm and Fordyce's study design and hypothesis representation.
- Clarification of the oscillation hypothesis and derivation of testable predictions.
- Reanalysis of existing data, highlighting sensitivity of specific statistical models (e.g., SSE class).
Main Results:
- Hamm and Fordyce's study misrepresented the oscillation hypothesis and employed flawed methods.
- The reanalysis revealed significant sensitivity of SSE models to minor specification changes, questioning their reliability for trait-based diversification tests.
- Apparent conflicts between the oscillation hypothesis and Hamm and Fordyce's findings may stem from methodological issues.
Conclusions:
- The oscillation hypothesis remains a viable explanation for insect diversification.
- Caution is advised against using SSE models for trait-based diversification tests due to their instability.
- Future research should focus on refining methods and better incorporating the mechanisms driving host range oscillations.
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