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Published on: April 15, 2015
The emergence of modularity in biological systems
Dirk M Lorenz1, Alice Jeng, Michael W Deem
1Department of Physics and Astronomy, Rice University, USA.
Physics of Life Reviews
|March 1, 2011
Summary
Biological systems exhibit modularity and hierarchy, organizing spontaneously from chemical possibilities. This review explores this structured form using examples across biology, from proteins to ecosystems.
Area of Science:
- Systems Biology
- Theoretical Biology
- Biophysics
Background:
- Biological systems display complex organization, including modularity and hierarchy.
- Understanding the spontaneous emergence of biological structure from chemical precursors is a fundamental challenge.
Purpose of the Study:
- To review theories explaining the modular organization of biological systems.
- To describe the emergence of biological modularity as a symmetry-breaking phase transition.
- To present experimental evidence supporting this theoretical framework.
Main Methods:
- Review of existing literature on modularity and hierarchy in biological systems.
- Analysis of examples from diverse biological scales, including molecular, genetic, ecological, and social networks.
- Theoretical framing of biological organization as a phase transition phenomenon.
Main Results:
- Modularity is a key organizational principle observed across various biological scales.
- Biological structure can emerge spontaneously, akin to a phase transition in physics.
- Experimental data from diverse biological networks support the symmetry-breaking model.
Conclusions:
- Modularity provides a framework for understanding the structured organization of life.
- The emergence of biological complexity can be explained through physical principles like phase transitions.
- This perspective unifies observations across disparate biological fields.
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