Signals and Boundaries

Building Blocks for Complex Adaptive Systems

Complex adaptive systems (cas), including ecosystems, governments, biological cells, and markets, are characterized by intricate hierarchical arrangements of boundaries and signals. In ecosystems, for example, niches act as semi-permeable boundaries, and smells and visual patterns serve as signals; governments have departmental hierarchies with memoranda acting as signals; and so it is with other cas. Despite a wealth of data and descriptions concerning different cas, there remain many unanswered questions about "steering" these systems. In Signals and Boundaries, John Holland argues that understanding the origin of the intricate signal/border hierarchies of these systems is the key to answering such questions. He develops an overarching framework for comparing and steering cas through the mechanisms that generate their signal/boundary hierarchies.

Holland lays out a path for developing the framework that emphasizes agents, niches, theory, and mathematical models. He discusses, among other topics, theory construction; signal-processing agents; networks as representations of signal/boundary interaction; adaptation; recombination and reproduction; the use of tagged urn models (adapted from elementary probability theory) to represent boundary hierarchies; finitely generated systems as a way to tie the models examined into a single framework; the framework itself, illustrated by a simple finitely generated version of the development of a multi-celled organism; and Markov processes.

Table of Contents

  1. Preface
  2. 1. The Roles of Signals and Boundaries
  3. 2. Theory and Models: General Principles
  4. 3. Agents and Signal Processing
  5. 4. Networks and Flows
  6. 5. Adaptation
  7. 6. Recombination and Reproduction
  8. 7. Urn Models of Boundaries
  9. 8. Boundary Hierarchies
  10. 9. The Evolution of Niches-A First Look
  11. 10. Language: Grammars and Niches
  12. 11. Grammars as Finitely Generated Systems
  13. 12. An Overarching Signal/Boundary Framework
  14. 13. A Dynamic Generated System Model of Ontogeny
  15. 14. A Complete Dynamic Generated System for Signal/Boundary Studies
  16. 15. Mathematical Models of Generated Structures
  17. 16. A Short Version of the Whole
  18. References
  19. Index