punctuated equilibrium


Also found in: Thesaurus, Medical, Acronyms, Encyclopedia, Wikipedia.

punc·tu·at·ed equilibrium

(pŭngk′cho͞o-ā′tĭd)
n.
1. The theory that the evolution of life on earth typically follows a pattern in which long periods of little morphological change are punctuated by relatively short periods of significant change, when speciation occurs.
2. Evolutionary development of this kind.

punc′tuated equilib′rium


n.
a theory that the evolution of species proceeds with long periods of relative stability interspersed with rapid change. Compare gradualism (def. 2).
[1972]

punc·tu·at·ed equilibrium

(pŭngk′cho͞o-ā′tĭd)
The theory that new species evolve suddenly over relatively short periods of time, followed by longer periods in which little genetic change occurs. Punctuated equilibrium is a revision of Darwin's theory that evolution takes place at a slow, constant rate over millions of years. Compare gradualism. See Note at evolution.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.punctuated equilibrium - a theory of evolution holding that evolutionary change in the fossil record came in fits and starts rather than in a steady process of slow change
evolutionism, theory of evolution, theory of organic evolution - (biology) a scientific theory of the origin of species of plants and animals
References in periodicals archive ?
Another purpose of the study was to determine if, as predicted by punctuated equilibrium theory, radical organizational changes are more effective in withdrawing commitment to runaway projects than are incremental measures.
The natural history of knee osteoarthritis often is a process of punctuated equilibrium, with periods of metabolic activation and progression, interspersed with periods of relative nonprogression and metabolic dormancy.
2) We have resisted becoming a participant in such a ratcheting process, by which periods of punctuated equilibrium periodically occur in which the law lurches in the direction favored by Justice Douglas and his philosophical allies, during which new precedents arise bearing little more than a random relationship to the written law, only to be followed by periods of conservative judicial rule in which these new precedents are affirmed in the interests of stare decisis and become a permanent fixture of the law.
In one chapter of Punctuated Equilibrium, political scientist Frank Baumgartner writes similarly of "social cascade effects.
This is likely the pattern recognized in Niles Eldredge and Stephen Gould's punctuated equilibrium (Eldredge and Gould 1972; Gould 1980).
While punctuated equilibrium (PE) reflected in the fossil record is a strong negative evidence to the underlying principle of phyletic gradualism (PG) enshrined in the evolutionary theory, the phenomenon of cell-directed mutagenesis challenges another tenet of the theory, namely, the requirement of stochastic mutations produced by extra-cellular agents to create heritable changes in the organism.
The book is sown through with a vocabulary of adaptive organisms, fitness, punctuated equilibrium, replication and other concepts from evolutionary science.
then demonstrates how application of Whitehead's naturalism can overcome these difficulties, providing a rationale for, and an understanding of, the emergence of higher-level actualities and the theory of punctuated equilibrium.