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Updated: Jul 15, 2026
12:02
Molecular Evolution of the Tre Recombinase
Published on: May 29, 2008
The evolutionary origin of cooperators and defectors
Michael Doebeli1, Christoph Hauert, Timothy Killingback
1Department of Zoology and Department of Mathematics, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. doebeli@zoology.ubc.ca
Science (New York, N.Y.)
|October 30, 2004
Summary
Evolutionary diversification arises when individuals benefit from their own cooperative acts. This study shows how cooperators and defectors coexist by evolving large investment asymmetries in the continuous snowdrift game.
Area of Science:
- Evolutionary biology
- Game theory
- Behavioral ecology
Background:
- Coexistence of cooperators and defectors is frequently observed in nature.
- The evolutionary origins of social diversity remain poorly understood.
- Previous models often assumed cooperative benefits accrue only to others.
Purpose of the Study:
- To investigate the evolutionary dynamics of cooperation when individuals also benefit from their own actions.
- To analyze the continuous snowdrift game with self-beneficial cooperative acts.
- To understand the conditions leading to social diversification.
Main Methods:
- Analysis of the continuous snowdrift game.
- Modeling adaptive dynamics of investment levels.
- Investigating evolutionary diversification from uniform populations.
Main Results:
- Cooperative investments are costly but provide benefits to both the cooperator and others.
- Adaptive dynamics lead to evolutionary diversification.
- A stable state emerges where cooperators with high investments coexist with defectors with low investments.
- Large asymmetries in cooperative investments can evolve.
Conclusions:
- When individuals benefit from their own cooperative actions, social diversification is possible.
- The continuous snowdrift game provides a framework for understanding the evolution of cooperation and defection.
- Self-benefit in cooperation drives significant investment asymmetries, explaining coexistence patterns.
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