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Adaptive genetic structure in phytophagous insect populations.
1Susan Mopper is at the Dept of Biology, University of Southwestern Louisiana, Lafayette, LA 70504-2451, USA.
Trends in Ecology & Evolution
|January 18, 2011
Summary
Insect genetic variation often forms discrete groups, or demes, adapting to diverse host plants. Host-plant traits drive rapid adaptive evolution in phytophagous insects, especially endophagous species.
Area of Science:
- Ecology
- Evolutionary Biology
- Entomology
Background:
- Insect genetic variation frequently structures into discrete groups (demes).
- Phytophagous insects inhabit heterogeneous host-plant populations, potentially leading to deme adaptation.
- Plant-mediated selection is a key factor in insect evolution.
Purpose of the Study:
- To investigate adaptive deme formation in phytophagous insects.
- To understand the role of host-plant traits in driving insect adaptive evolution.
- To compare selection pressures on endophagous versus externally feeding insects.
Main Methods:
- Field experiments were conducted to observe insect populations.
- Selection pressures imposed by host plants were analyzed.
- Genetic variation and population structure were assessed.
Main Results:
- Host-plant traits can promote rapid adaptive evolution in insect populations at fine spatial scales.
- Adaptive deme formation is influenced by host-plant heterogeneity.
- Endophagous insects experience stronger plant-mediated selection pressures than external feeders.
Conclusions:
- Host-plant adaptation is a significant driver of deme formation in phytophagous insects.
- Fine-scale adaptive evolution is facilitated by plant-mediated selection.
- Endophagy may enhance adaptive divergence due to intensified host-plant interactions.
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