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

Graudal speciation and punctuated equilibrium both result in the divergence of species.

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

The term punctuated equilibrium refers to the fact that fossil records have shown that, in evolution, there have been periods of relative stasis or equilibrium punctuated by periods of very rapid change.

From Salon • Mar. 9, 2014