Others have said twice: it is called Punctuated Equilibrium.
Concept called gradualism. Not hypothesis, as it has been tested and confirmed, especially among the " little shellies. "
natural selection
This is the concept of gradualism.
That theory is called punctuated equilibrium.
punctuated equilibrium
The punctuated equilibrium theory suggests that evolution occurs in rapid bursts of change interspersed with long periods of stasis. It proposes that species experience sudden bursts of evolutionary change due to localized environmental pressures, followed by extended periods of little to no change. This theory contrasts with the gradualism model, which suggests a constant and gradual rate of evolution over time.
The smallest unit in which evolution occurs is a population.
The three main theories of evolution are Lamarckism, Darwinism, and punctuated equilibrium. Lamarckism suggests that organisms can pass on acquired traits to their offspring, while Darwinism proposes natural selection as the main mechanism of evolution. Punctuated equilibrium suggests that evolution occurs in rapid bursts separated by long periods of stability.
Evolution occurs when life forms reproduce with genetic variation of inherited traits, within an environment with a limited carrying capacity (which is basically all environments). In other words, evolution happens where life as we know it exists.
One is that evolution occurs gradually and consistently.The other is that evolution occurs as a result of competition for 'niches'
Lamarck believed that there was a form of evolution, but contrary to Darwin after him, he believed that the characteristics an organism acquires during his life are inherited by its descendants. For more on Lamarck's hypothesis, see the related question below.
Darwin's classic theory of evolution assumed that evolution is a slow, contunuous process, by which new species evolve and emerge. This is referred to at times as "organic evolution" and the "synthetic theory of evolution", or just the Darwinian theory of evolution. A newer theory, proposed originally by Niles Eldridge and Stephen Jay Gould is known as "punctuated equilibria", a model in which the evloution of new species occurs only periodically, in relatively rapid spurts. See "Time Frames the Rethinking of Darwinian Evolution and the Theory of Punctuated Equilibraia, Simon & Schuster, 1985"AnswerThe slow, constant process has also been called "gradualism."