punctuated equilibrium

American  

noun

1. Biology. theory of, a hypothesis holding that the evolution of species proceeds in a characteristic pattern of relative stability for long periods of time interspersed with much shorter periods during which many species become extinct and new species emerge.

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punctuated equilibrium Scientific  

/ pŭngk′cho̅o̅-ā′tĭd /

1. The theory that new species evolve suddenly over relatively short periods of time (a few hundred to a thousand years), 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.

2. Compare gradualism See Note at evolution

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punctuated equilibrium Cultural  

1. The theory that new species evolve suddenly over brief periods of time, followed by longer periods during which there is no genetic change. Punctuated equilibrium is a revision of Darwin's theory of evolution. (Compare gradualism and catastrophism.)

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Etymology

Origin of punctuated equilibrium

Coined by Stephen Jay Gould ( def. ) and Niles Eldredge, American biologist and paleontologist (born 1943), in their paper “Punctuated equilibria: an alternative to phyletic gradualism” (1972)

Compare meaning

How does punctuated-equilibrium compare to similar and commonly confused words? Explore the most common comparisons:

• gradualism vs. punctuated equilibrium

Example Sentences

See Examples For:

punctuated equilibrium

In terms of how quickly speciation occurs, two patterns are currently observed: gradual speciation model and punctuated equilibrium model.

From Textbooks ● Jun. 9, 2022

The students suggested these factors: natural selection, morphological mutations, punctuated equilibrium and allopatric speciation.

From Washington Post ● Feb. 20, 2022

One of the findings that stands out, he says, is that pop music shows a pattern from biological evolution known as punctuated equilibrium, in which periods of gradual change are separated by explosions of complexity.

From Science Magazine ● May 5, 2015

In the punctuated equilibrium example, as in the graduated speciation example, the founder species diverges into one species with a hooked break and another with a straight beak.

From Textbooks ● Jan. 1, 2015

Besides the founder effect, another phenomenon of special interest from evolutionary biology is punctuated equilibrium.

From Salon ● Mar. 9, 2014