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However, the punctuational equilibrium model may still be inferred from both the observation of stasis and examples of rapid and episodic speciation events documented in the fossil record. [70] Dawkins also emphasizes that punctuated equilibrium has been "oversold by some journalists", [71] but partly due to Eldredge and Gould's "later writings ...
Also, members of older groups tended to perceive their groups to have more of the characteristics of Stage-3 and Stage-4 groups and to be more productive. Based on these results, Wheelan's position supports the traditional linear models of group development and casts doubt on the cyclic models and Gersick's punctuated equilibrium model.
The punctuated equilibrium model of policy change was first presented by Frank Baumgartner and Bryan Jones in 1993, [1] and has increasingly received attention in historical institutionalism. [3] The model states that policy generally changes only incrementally due to several restraints, namely the "stickiness" of institutional cultures, vested ...
Gould's most significant contribution to evolutionary biology was the theory of punctuated equilibrium [2] developed with Niles Eldredge in 1972. [3] The theory proposes that most evolution is characterized by long periods of evolutionary stability, infrequently punctuated by swift periods of branching speciation.
Speciation is the evolutionary process by which populations evolve to become distinct species.The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages.
The Bak–Sneppen model is a simple model of co-evolution between interacting species. It was developed to show how self-organized criticality may explain key features of the fossil record, such as the distribution of sizes of extinction events and the phenomenon of punctuated equilibrium .
Dawkins could, should, and probably would accept it; in The Ancestor's Tale, he has an inclusive view of speciation mechanisms." (p. 100) Thus, while "Gould somewhat overstates the adherence of orthodoxy to strict extrapolationism", punctuated equilibrium is more important than some of the more "ungenerous treatment" that has been meted out.
Additionally, scientists research the 'tempo' of speciation, i.e. the rate at which species change genetically and/or morphologically. Classically, competing hypothesis for the tempo of specieation include phyletic gradualism and punctuated equilibrium). Lastly, what are the causes of speciation is also extensively researched. [1]