Journal of Statistical Physics

, Volume 144, Issue 2, pp 268–302 | Cite as

Are Biological Systems Poised at Criticality?

  • Thierry Mora
  • William BialekEmail author


Many of life’s most fascinating phenomena emerge from interactions among many elements—many amino acids determine the structure of a single protein, many genes determine the fate of a cell, many neurons are involved in shaping our thoughts and memories. Physicists have long hoped that these collective behaviors could be described using the ideas and methods of statistical mechanics. In the past few years, new, larger scale experiments have made it possible to construct statistical mechanics models of biological systems directly from real data. We review the surprising successes of this “inverse” approach, using examples from families of proteins, networks of neurons, and flocks of birds. Remarkably, in all these cases the models that emerge from the data are poised near a very special point in their parameter space—a critical point. This suggests there may be some deeper theoretical principle behind the behavior of these diverse systems.


Critical point Maximum entropy model Biological networks Proteins Collective behavior 


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© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Joseph Henry Laboratories of Physics, Lewis-Sigler Institute for Integrative GenomicsPrinceton UniversityPrincetonUSA
  2. 2.Laboratoire de Physique Statistique de l’École Normale SupérieureUMR 8550 of CNRS associated with Universities Paris 6 et Paris 7Paris Cedex 05France

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