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Updated: Jul 25, 2026
09:23
Methodology for Developing Life Tables for Sessile Insects in the Field Using the Whitefly, Bemisia tabaci, in Cotton As a Model System
Published on: November 1, 2017
Density-dependent physiological phase in insects
1Department of Entomology, Faculty of Agriculture, The Hebrew University, Rehovot 76100, Israel. shalom@agri.huji.ac.il
Annual Review of Entomology
|March 12, 2004
Summary
Insect crowding triggers rapid behavioral shifts and long-term physical changes. These responses depend on density, duration, and maternal history, impacting insect populations.
Area of Science:
- Entomology
- Ecology
- Animal Behavior
Background:
- Insects exhibit diverse responses to crowding, including behavioral, morphological, and chromatic changes.
- These responses are graded, influenced by population density, exposure duration, and maternal generation's phase history.
Purpose of the Study:
- To elucidate the mechanisms and ecological significance of insect responses to crowding.
- To differentiate between short-term and long-term adaptive strategies in response to population density.
Main Methods:
- Observational studies on insect behavior and morphology.
- Analysis of physiological and biochemical changes in response to varying population densities.
- Investigation of sensory pathways and signal transduction mechanisms.
Main Results:
- Overt morphological and chromatic changes are linked to molting periods due to exoskeleton constraints.
- Internal physiological and metabolic changes occur independently of the molting cycle.
- Intraspecific responses, including migration, are mediated by sensory systems and signal transduction pathways.
Conclusions:
- Insect responses to crowding are complex, involving both immediate behavioral adjustments and delayed physical alterations.
- The timing of external responses is constrained by the exoskeleton, while internal changes offer greater flexibility.
- These density-dependent responses are ecologically significant, influencing insect movement and population dynamics.
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