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Updated: Aug 3, 2026

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Drosophila Adult Olfactory Shock Learning
Published on: August 8, 2014
Memory and self-induced shocks in an evolutionary population competing for limited resources
1Physics Department, Oxford University, Parks Road, Oxford, QX1 3PU, United Kingdom. roland.kay@physics.ox.ac.uk
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 17, 2004
Summary
Memory and self-induced shocks significantly influence evolutionary populations competing for resources. Microscopic changes in extreme subgroups control macroscopic population shifts.
Area of Science:
- Evolutionary dynamics
- Complex systems
- Agent-based modeling
Background:
- Builds upon a previously introduced multiagent system known for self-segregation and population freezing.
- The system models populations competing for limited resources, exhibiting complex emergent behaviors.
Purpose of the Study:
- To investigate the role of memory and self-induced shocks in an evolutionary population.
- To understand the mechanisms driving large-scale changes in the multiagent system.
Main Methods:
- Utilizes a multiagent system simulation.
- Analyzes population dynamics based on a 'gene' value (p) ranging from 0 to 1.
- Examines transitions to 'frozen' populations and self-induced macroscopic changes.
Main Results:
- Identified memory as a key factor in population dynamics.
- Demonstrated that macroscopic self-induced shocks are controlled by microscopic changes in extreme subgroups (p ≈ 0 and p ≈ 1).
- Observed population freezing as a function of global resource levels.
Conclusions:
- Microscopic behaviors within extreme population subgroups are critical drivers of large-scale evolutionary dynamics.
- Memory plays a crucial role in the emergence and control of self-induced shocks in resource-limited populations.
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